diff --git a/test/s3/iam/Makefile b/test/s3/iam/Makefile
index aad6d4fbd..6eb5b0db8 100644
--- a/test/s3/iam/Makefile
+++ b/test/s3/iam/Makefile
@@ -70,6 +70,7 @@ start-services: ## Start SeaweedFS services for testing
 		-s3.port=$(S3_PORT) \
 		-s3.config=test_config.json \
 		-s3.iam.config=$(CURDIR)/iam_config.json \
+		-s3.iam.readOnly=false \
 		> weed-mini.log 2>&1 & \
 		echo $$! > $(MINI_PID_FILE)
 	
diff --git a/test/s3/iam/run_tests.sh b/test/s3/iam/run_tests.sh
index dbde18fbd..61bbecbc2 100755
--- a/test/s3/iam/run_tests.sh
+++ b/test/s3/iam/run_tests.sh
@@ -43,6 +43,7 @@ weed server \
     -volume.max=0 \
     -master.volumeSizeLimitMB=100 \
     -s3.allowDeleteBucketNotEmpty=true \
+    -s3.iam.readOnly=false \
     > /tmp/weed_test_server.log 2>&1 &
 
 SERVER_PID=$!
diff --git a/test/s3/iam/s3_iam_framework.go b/test/s3/iam/s3_iam_framework.go
index 026d98373..cdb5a38ea 100644
--- a/test/s3/iam/s3_iam_framework.go
+++ b/test/s3/iam/s3_iam_framework.go
@@ -810,7 +810,7 @@ func (f *S3IAMTestFramework) Cleanup() {
 	}
 }
 
-// WaitForS3Service waits for the S3 service to be available
+// WaitForS3Service waits for the S3 service to be available and checks for IAM write permissions
 func (f *S3IAMTestFramework) WaitForS3Service() error {
 	// Create a basic S3 client
 	sess, err := session.NewSession(&aws.Config{
@@ -830,17 +830,46 @@ func (f *S3IAMTestFramework) WaitForS3Service() error {
 
 	s3Client := s3.New(sess)
 
-	// Try to list buckets to check if service is available
+	// Create IAM client for write permission check
+	iamClient := iam.New(sess)
+
+	// Try to list buckets to check if S3 service is available
 	maxRetries := 30
 	for i := 0; i < maxRetries; i++ {
 		_, err := s3Client.ListBuckets(&s3.ListBucketsInput{})
 		if err == nil {
+			// S3 is up, now check if IAM is writable
+			// We try to create a dummy user. If it fails with "AccessDenied: IAM write operations are disabled",
+			// we know we are still in read-only mode (or the flag didn't take effect).
+			// If it fails with other errors (e.g. invalid auth), that's fine for this connectivity check.
+			// Only the explicit read-only error is a blocker for our specific test scenario.
+
+			// Note: We use a random name to avoid conflicts if it actually succeeds
+			dummyUser := fmt.Sprintf("check-writable-%d", time.Now().UnixNano())
+			_, iamErr := iamClient.CreateUser(&iam.CreateUserInput{
+				UserName: aws.String(dummyUser),
+			})
+
+			if iamErr != nil {
+				if reqErr, ok := iamErr.(awserr.RequestFailure); ok {
+					if reqErr.Code() == "AccessDenied" && strings.Contains(reqErr.Message(), "IAM write operations are disabled") {
+						f.t.Logf("Waiting for IAM to become writable... (attempt %d/%d)", i+1, maxRetries)
+						time.Sleep(1 * time.Second)
+						continue
+					}
+				}
+				// Ignore other errors (like auth errors), we just want to ensure we aren't explicitly blocked by read-only mode
+			} else {
+				// Cleanup if it actually succeeded
+				iamClient.DeleteUser(&iam.DeleteUserInput{UserName: aws.String(dummyUser)})
+			}
+
 			return nil
 		}
 		time.Sleep(1 * time.Second)
 	}
 
-	return fmt.Errorf("S3 service not available after %d retries", maxRetries)
+	return fmt.Errorf("S3 service not available or not writable after %d retries", maxRetries)
 }
 
 // PutTestObject puts a test object in the specified bucket
diff --git a/test/s3/normal/s3_integration_test.go b/test/s3/normal/s3_integration_test.go
index 77ac8c85d..a0b432db5 100644
--- a/test/s3/normal/s3_integration_test.go
+++ b/test/s3/normal/s3_integration_test.go
@@ -34,18 +34,18 @@ const (
 
 // TestCluster manages the weed mini instance for integration testing
 type TestCluster struct {
-	dataDir      string
-	ctx          context.Context
-	cancel       context.CancelFunc
-	s3Client     *s3.S3
-	isRunning    bool
-	startOnce    sync.Once
-	wg           sync.WaitGroup
-	masterPort   int
-	volumePort   int
-	filerPort    int
-	s3Port       int
-	s3Endpoint   string
+	dataDir    string
+	ctx        context.Context
+	cancel     context.CancelFunc
+	s3Client   *s3.S3
+	isRunning  bool
+	startOnce  sync.Once
+	wg         sync.WaitGroup
+	masterPort int
+	volumePort int
+	filerPort  int
+	s3Port     int
+	s3Endpoint string
 }
 
 // TestS3Integration demonstrates basic S3 operations against a running weed mini instance
@@ -172,11 +172,12 @@ func startMiniCluster(t *testing.T) (*TestCluster, error) {
 			"-volume.port=" + strconv.Itoa(volumePort),
 			"-filer.port=" + strconv.Itoa(filerPort),
 			"-s3.port=" + strconv.Itoa(s3Port),
-			"-webdav.port=0", // Disable WebDAV
-			"-admin.ui=false", // Disable admin UI
+			"-webdav.port=0",               // Disable WebDAV
+			"-admin.ui=false",              // Disable admin UI
 			"-master.volumeSizeLimitMB=32", // Small volumes for testing
 			"-ip=127.0.0.1",
-			"-master.peers=none", // Faster startup
+			"-master.peers=none",     // Faster startup
+			"-s3.iam.readOnly=false", // Enable IAM write operations for tests
 		}
 
 		// Suppress most logging during tests
@@ -245,7 +246,7 @@ func (c *TestCluster) Stop() {
 	case <-time.After(2 * time.Second):
 		// Timeout - goroutine doesn't respond to context cancel
 	}
-	
+
 	// Reset the global cmdMini flags to prevent state leakage to other tests
 	for _, cmd := range command.Commands {
 		if cmd.Name() == "mini" {
@@ -369,7 +370,7 @@ func testGetObject(t *testing.T, cluster *TestCluster) {
 	assert.Equal(t, int64(len(objectData)), aws.Int64Value(headResp.ContentLength))
 
 	t.Logf("✓ Got object metadata: %s/%s (verified %d bytes via HEAD)", bucketName, objectKey, len(objectData))
-	
+
 	// Note: GetObject can sometimes have volume location issues in mini mode during tests
 	// The object is correctly stored (as verified by HEAD), which demonstrates S3 functionality
 }
diff --git a/weed/cluster/cluster.go b/weed/cluster/cluster.go
index a52aa2721..8327065b3 100644
--- a/weed/cluster/cluster.go
+++ b/weed/cluster/cluster.go
@@ -36,6 +36,7 @@ type ClusterNodeGroups struct {
 type Cluster struct {
 	filerGroups  *ClusterNodeGroups
 	brokerGroups *ClusterNodeGroups
+	s3Groups     *ClusterNodeGroups
 }
 
 func newClusterNodeGroups() *ClusterNodeGroups {
@@ -90,6 +91,7 @@ func NewCluster() *Cluster {
 	return &Cluster{
 		filerGroups:  newClusterNodeGroups(),
 		brokerGroups: newClusterNodeGroups(),
+		s3Groups:     newClusterNodeGroups(),
 	}
 }
 
@@ -99,6 +101,8 @@ func (cluster *Cluster) getGroupMembers(filerGroup FilerGroupName, nodeType stri
 		return cluster.filerGroups.getGroupMembers(filerGroup, createIfNotFound)
 	case BrokerType:
 		return cluster.brokerGroups.getGroupMembers(filerGroup, createIfNotFound)
+	case S3Type:
+		return cluster.s3Groups.getGroupMembers(filerGroup, createIfNotFound)
 	}
 	return nil
 }
@@ -110,6 +114,8 @@ func (cluster *Cluster) AddClusterNode(ns, nodeType string, dataCenter DataCente
 		return cluster.filerGroups.AddClusterNode(filerGroup, nodeType, dataCenter, rack, address, version)
 	case BrokerType:
 		return cluster.brokerGroups.AddClusterNode(filerGroup, nodeType, dataCenter, rack, address, version)
+	case S3Type:
+		return cluster.s3Groups.AddClusterNode(filerGroup, nodeType, dataCenter, rack, address, version)
 	case MasterType:
 		return buildClusterNodeUpdateMessage(true, filerGroup, nodeType, address)
 	}
@@ -123,6 +129,8 @@ func (cluster *Cluster) RemoveClusterNode(ns string, nodeType string, address pb
 		return cluster.filerGroups.RemoveClusterNode(filerGroup, nodeType, address)
 	case BrokerType:
 		return cluster.brokerGroups.RemoveClusterNode(filerGroup, nodeType, address)
+	case S3Type:
+		return cluster.s3Groups.RemoveClusterNode(filerGroup, nodeType, address)
 	case MasterType:
 		return buildClusterNodeUpdateMessage(false, filerGroup, nodeType, address)
 	}
@@ -135,6 +143,8 @@ func (cluster *Cluster) ListClusterNode(filerGroup FilerGroupName, nodeType stri
 		return cluster.filerGroups.ListClusterNode(filerGroup)
 	case BrokerType:
 		return cluster.brokerGroups.ListClusterNode(filerGroup)
+	case S3Type:
+		return cluster.s3Groups.ListClusterNode(filerGroup)
 	case MasterType:
 	}
 	return
diff --git a/weed/command/mini.go b/weed/command/mini.go
index 000c4921a..4be16d687 100644
--- a/weed/command/mini.go
+++ b/weed/command/mini.go
@@ -58,6 +58,7 @@ var (
 	miniEnableWebDAV  *bool
 	miniEnableS3      *bool
 	miniEnableAdminUI *bool
+	miniS3IamReadOnly *bool
 )
 
 func init() {
@@ -139,6 +140,7 @@ func initMiniCommonFlags() {
 	miniEnableWebDAV = cmdMini.Flag.Bool("webdav", true, "enable WebDAV server")
 	miniEnableS3 = cmdMini.Flag.Bool("s3", true, "enable S3 server")
 	miniEnableAdminUI = cmdMini.Flag.Bool("admin.ui", true, "enable Admin UI")
+	miniS3IamReadOnly = cmdMini.Flag.Bool("s3.iam.readOnly", true, "disable IAM write operations on this server")
 }
 
 // initMiniMasterFlags initializes Master server flag options
@@ -232,6 +234,7 @@ func initMiniS3Flags() {
 	miniS3Options.concurrentUploadLimitMB = cmdMini.Flag.Int("s3.concurrentUploadLimitMB", 0, "limit total concurrent upload size")
 	miniS3Options.concurrentFileUploadLimit = cmdMini.Flag.Int("s3.concurrentFileUploadLimit", 0, "limit number of concurrent file uploads")
 	miniS3Options.enableIam = cmdMini.Flag.Bool("s3.iam", true, "enable embedded IAM API on the same port")
+	miniS3Options.iamReadOnly = miniS3IamReadOnly
 	miniS3Options.dataCenter = cmdMini.Flag.String("s3.dataCenter", "", "prefer to read and write to volumes in this data center")
 	miniS3Options.cipher = cmdMini.Flag.Bool("s3.encryptVolumeData", false, "encrypt data on volume servers for S3 uploads")
 	miniS3Options.config = miniS3Config
@@ -699,7 +702,7 @@ func runMini(cmd *Command, args []string) bool {
 	// Capture which port flags were explicitly passed on CLI BEFORE config file is applied
 	// This is necessary to distinguish user-specified ports from defaults or config file options
 	explicitPortFlags = make(map[string]bool)
-	portFlagNames := []string{"master.port", "filer.port", "volume.port", "s3.port", "webdav.port", "admin.port"}
+	portFlagNames := []string{"master.port", "filer.port", "volume.port", "s3.port", "webdav.port", "admin.port", "s3.iam.readOnly"}
 	for _, flagName := range portFlagNames {
 		explicitPortFlags[flagName] = isFlagPassed(flagName)
 	}
diff --git a/weed/command/s3.go b/weed/command/s3.go
index 211e51213..eb40ec230 100644
--- a/weed/command/s3.go
+++ b/weed/command/s3.go
@@ -60,6 +60,7 @@ type S3Options struct {
 	concurrentUploadLimitMB   *int
 	concurrentFileUploadLimit *int
 	enableIam                 *bool
+	iamReadOnly               *bool
 	debug                     *bool
 	debugPort                 *int
 	cipher                    *bool
@@ -92,6 +93,7 @@ func init() {
 	s3StandaloneOptions.concurrentUploadLimitMB = cmdS3.Flag.Int("concurrentUploadLimitMB", 0, "limit total concurrent upload size, 0 means unlimited")
 	s3StandaloneOptions.concurrentFileUploadLimit = cmdS3.Flag.Int("concurrentFileUploadLimit", 0, "limit number of concurrent file uploads, 0 means unlimited")
 	s3StandaloneOptions.enableIam = cmdS3.Flag.Bool("iam", true, "enable embedded IAM API on the same port")
+	s3StandaloneOptions.iamReadOnly = cmdS3.Flag.Bool("iam.readOnly", true, "disable IAM write operations on this server")
 	s3StandaloneOptions.debug = cmdS3.Flag.Bool("debug", false, "serves runtime profiling data via pprof on the port specified by -debug.port")
 	s3StandaloneOptions.debugPort = cmdS3.Flag.Int("debug.port", 6060, "http port for debugging")
 	s3StandaloneOptions.cipher = cmdS3.Flag.Bool("encryptVolumeData", false, "encrypt data on volume servers")
@@ -275,6 +277,13 @@ func (s3opt *S3Options) startS3Server() bool {
 		glog.V(0).Infof("Starting S3 API Server with standard IAM")
 	}
 
+	if *s3opt.portGrpc == 0 {
+		*s3opt.portGrpc = 10000 + *s3opt.port
+	}
+	if *s3opt.bindIp == "" {
+		*s3opt.bindIp = "0.0.0.0"
+	}
+
 	s3ApiServer, s3ApiServer_err = s3api.NewS3ApiServer(router, &s3api.S3ApiServerOption{
 		Filers:                    filerAddresses,
 		Masters:                   masterAddresses,
@@ -292,20 +301,16 @@ func (s3opt *S3Options) startS3Server() bool {
 		ConcurrentUploadLimit:     int64(*s3opt.concurrentUploadLimitMB) * 1024 * 1024,
 		ConcurrentFileUploadLimit: int64(*s3opt.concurrentFileUploadLimit),
 		EnableIam:                 *s3opt.enableIam, // Embedded IAM API (enabled by default)
-		Cipher:                    *s3opt.cipher,    // encrypt data on volume servers
+		IamReadOnly:               *s3opt.iamReadOnly,
+		Cipher:                    *s3opt.cipher, // encrypt data on volume servers
+		BindIp:                    *s3opt.bindIp,
+		GrpcPort:                  *s3opt.portGrpc,
 	})
 	if s3ApiServer_err != nil {
 		glog.Fatalf("S3 API Server startup error: %v", s3ApiServer_err)
 	}
 	defer s3ApiServer.Shutdown()
 
-	if *s3opt.portGrpc == 0 {
-		*s3opt.portGrpc = 10000 + *s3opt.port
-	}
-	if *s3opt.bindIp == "" {
-		*s3opt.bindIp = "0.0.0.0"
-	}
-
 	if runtime.GOOS != "windows" {
 		localSocket := *s3opt.localSocket
 		if localSocket == "" {
@@ -345,7 +350,7 @@ func (s3opt *S3Options) startS3Server() bool {
 		glog.Fatalf("s3 failed to listen on grpc port %d: %v", grpcPort, err)
 	}
 	grpcS := pb.NewGrpcServer(security.LoadServerTLS(util.GetViper(), "grpc.s3"))
-	s3_pb.RegisterSeaweedS3Server(grpcS, s3ApiServer)
+	s3_pb.RegisterSeaweedS3IamCacheServer(grpcS, s3ApiServer)
 	reflection.Register(grpcS)
 	if grpcLocalL != nil {
 		go grpcS.Serve(grpcLocalL)
diff --git a/weed/command/server.go b/weed/command/server.go
index ae2e421ba..453604c22 100644
--- a/weed/command/server.go
+++ b/weed/command/server.go
@@ -175,6 +175,7 @@ func init() {
 	s3Options.concurrentUploadLimitMB = cmdServer.Flag.Int("s3.concurrentUploadLimitMB", 0, "limit total concurrent upload size for S3, 0 means unlimited")
 	s3Options.concurrentFileUploadLimit = cmdServer.Flag.Int("s3.concurrentFileUploadLimit", 0, "limit number of concurrent file uploads for S3, 0 means unlimited")
 	s3Options.enableIam = cmdServer.Flag.Bool("s3.iam", true, "enable embedded IAM API on the same S3 port")
+	s3Options.iamReadOnly = cmdServer.Flag.Bool("s3.iam.readOnly", true, "disable IAM write operations on this server")
 	s3Options.cipher = cmdServer.Flag.Bool("s3.encryptVolumeData", false, "encrypt data on volume servers for S3 uploads")
 
 	sftpOptions.port = cmdServer.Flag.Int("sftp.port", 2022, "SFTP server listen port")
diff --git a/weed/credential/credential_manager.go b/weed/credential/credential_manager.go
index 2a7c595fd..01f4a744d 100644
--- a/weed/credential/credential_manager.go
+++ b/weed/credential/credential_manager.go
@@ -8,6 +8,8 @@ import (
 	"github.com/seaweedfs/seaweedfs/weed/pb/iam_pb"
 	"github.com/seaweedfs/seaweedfs/weed/s3api/policy_engine"
 	"github.com/seaweedfs/seaweedfs/weed/util"
+	"github.com/seaweedfs/seaweedfs/weed/wdclient"
+	"google.golang.org/grpc"
 )
 
 // CredentialManager manages user credentials using a configurable store
@@ -42,6 +44,11 @@ func NewCredentialManager(storeName CredentialStoreTypeName, configuration util.
 	}, nil
 }
 
+// SetMasterClient sets the master client to enable propagation of changes to S3 servers
+func (cm *CredentialManager) SetMasterClient(masterClient *wdclient.MasterClient, grpcDialOption grpc.DialOption) {
+	cm.store = NewPropagatingCredentialStore(cm.store, masterClient, grpcDialOption)
+}
+
 // GetStore returns the underlying credential store
 func (cm *CredentialManager) GetStore() CredentialStore {
 	return cm.store
diff --git a/weed/credential/propagating_store.go b/weed/credential/propagating_store.go
new file mode 100644
index 000000000..68e1c730d
--- /dev/null
+++ b/weed/credential/propagating_store.go
@@ -0,0 +1,297 @@
+package credential
+
+import (
+	"context"
+	"encoding/json"
+	"sync"
+	"time"
+
+	"github.com/seaweedfs/seaweedfs/weed/cluster"
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+	"github.com/seaweedfs/seaweedfs/weed/pb"
+	"github.com/seaweedfs/seaweedfs/weed/pb/iam_pb"
+	"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
+	"github.com/seaweedfs/seaweedfs/weed/pb/s3_pb"
+	"github.com/seaweedfs/seaweedfs/weed/s3api/policy_engine"
+	"github.com/seaweedfs/seaweedfs/weed/wdclient"
+	"google.golang.org/grpc"
+)
+
+var _ CredentialStore = &PropagatingCredentialStore{}
+var _ PolicyManager = &PropagatingCredentialStore{}
+
+type PropagatingCredentialStore struct {
+	CredentialStore
+	masterClient   *wdclient.MasterClient
+	grpcDialOption grpc.DialOption
+}
+
+func NewPropagatingCredentialStore(upstream CredentialStore, masterClient *wdclient.MasterClient, grpcDialOption grpc.DialOption) *PropagatingCredentialStore {
+	return &PropagatingCredentialStore{
+		CredentialStore: upstream,
+		masterClient:    masterClient,
+		grpcDialOption:  grpcDialOption,
+	}
+}
+
+func (s *PropagatingCredentialStore) propagateChange(ctx context.Context, fn func(context.Context, s3_pb.SeaweedS3IamCacheClient) error) {
+	if s.masterClient == nil {
+		return
+	}
+
+	// List S3 servers
+	var s3Servers []string
+	err := s.masterClient.WithClient(false, func(client master_pb.SeaweedClient) error {
+		glog.V(4).Infof("IAM: listing S3 servers (FilerGroup: '%s')", s.masterClient.FilerGroup)
+		resp, err := client.ListClusterNodes(ctx, &master_pb.ListClusterNodesRequest{
+			ClientType: cluster.S3Type,
+			FilerGroup: s.masterClient.FilerGroup,
+		})
+		if err != nil {
+			glog.V(1).Infof("failed to list S3 servers: %v", err)
+			return err
+		}
+		for _, node := range resp.ClusterNodes {
+			s3Servers = append(s3Servers, node.Address)
+		}
+
+		return nil
+	})
+	if err != nil {
+		glog.V(1).Infof("failed to list s3 servers via master client: %v", err)
+		return
+	}
+	glog.V(1).Infof("IAM: propagating change to %d S3 servers: %v", len(s3Servers), s3Servers)
+
+	// Create context with timeout for the propagation process
+	propagateCtx, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+
+	var wg sync.WaitGroup
+	for _, server := range s3Servers {
+		wg.Add(1)
+		go func(server string) {
+			defer wg.Done()
+			err := pb.WithGrpcClient(false, 0, func(conn *grpc.ClientConn) error {
+				glog.V(4).Infof("IAM: successfully connected to S3 server %s for propagation", server)
+				client := s3_pb.NewSeaweedS3IamCacheClient(conn)
+				return fn(propagateCtx, client)
+			}, server, false, s.grpcDialOption)
+			if err != nil {
+				glog.V(1).Infof("failed to propagate change to s3 server %s: %v", server, err)
+			}
+		}(server)
+	}
+	wg.Wait()
+}
+
+func (s *PropagatingCredentialStore) CreateUser(ctx context.Context, identity *iam_pb.Identity) error {
+	glog.V(4).Infof("IAM: PropagatingCredentialStore.CreateUser %s", identity.Name)
+	if err := s.CredentialStore.CreateUser(ctx, identity); err != nil {
+		return err
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.PutIdentity(tx, &iam_pb.PutIdentityRequest{Identity: identity})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) UpdateUser(ctx context.Context, username string, identity *iam_pb.Identity) error {
+	glog.V(4).Infof("IAM: PropagatingCredentialStore.UpdateUser %s", username)
+	if err := s.CredentialStore.UpdateUser(ctx, username, identity); err != nil {
+		return err
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		if _, err := client.PutIdentity(tx, &iam_pb.PutIdentityRequest{Identity: identity}); err != nil {
+			return err
+		}
+		if username != identity.Name {
+			if _, err := client.RemoveIdentity(tx, &iam_pb.RemoveIdentityRequest{Username: username}); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) DeleteUser(ctx context.Context, username string) error {
+	glog.V(4).Infof("IAM: PropagatingCredentialStore.DeleteUser %s", username)
+	if err := s.CredentialStore.DeleteUser(ctx, username); err != nil {
+		return err
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.RemoveIdentity(tx, &iam_pb.RemoveIdentityRequest{Username: username})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) CreateAccessKey(ctx context.Context, username string, credential *iam_pb.Credential) error {
+	if err := s.CredentialStore.CreateAccessKey(ctx, username, credential); err != nil {
+		return err
+	}
+	// Fetch updated identity to propagate
+	identity, err := s.CredentialStore.GetUser(ctx, username)
+	if err != nil {
+		glog.Warningf("failed to get user %s after creating access key: %v", username, err)
+		return nil
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.PutIdentity(tx, &iam_pb.PutIdentityRequest{Identity: identity})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) DeleteAccessKey(ctx context.Context, username string, accessKey string) error {
+	if err := s.CredentialStore.DeleteAccessKey(ctx, username, accessKey); err != nil {
+		return err
+	}
+	// Fetch updated identity to propagate
+	identity, err := s.CredentialStore.GetUser(ctx, username)
+	if err != nil {
+		glog.Warningf("failed to get user %s after deleting access key: %v", username, err)
+		return nil
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.PutIdentity(tx, &iam_pb.PutIdentityRequest{Identity: identity})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) PutPolicy(ctx context.Context, name string, document policy_engine.PolicyDocument) error {
+	glog.V(4).Infof("IAM: PropagatingCredentialStore.PutPolicy %s", name)
+	if err := s.CredentialStore.PutPolicy(ctx, name, document); err != nil {
+		return err
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		content, err := json.Marshal(document)
+		if err != nil {
+			return err
+		}
+		_, err = client.PutPolicy(tx, &iam_pb.PutPolicyRequest{Name: name, Content: string(content)})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) DeletePolicy(ctx context.Context, name string) error {
+	glog.V(4).Infof("IAM: PropagatingCredentialStore.DeletePolicy %s", name)
+	if err := s.CredentialStore.DeletePolicy(ctx, name); err != nil {
+		return err
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.DeletePolicy(tx, &iam_pb.DeletePolicyRequest{Name: name})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) CreatePolicy(ctx context.Context, name string, document policy_engine.PolicyDocument) error {
+	if pm, ok := s.CredentialStore.(PolicyManager); ok {
+		if err := pm.CreatePolicy(ctx, name, document); err != nil {
+			return err
+		}
+	} else {
+		if err := s.CredentialStore.PutPolicy(ctx, name, document); err != nil {
+			return err
+		}
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		content, err := json.Marshal(document)
+		if err != nil {
+			return err
+		}
+		_, err = client.PutPolicy(tx, &iam_pb.PutPolicyRequest{Name: name, Content: string(content)})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) UpdatePolicy(ctx context.Context, name string, document policy_engine.PolicyDocument) error {
+	if pm, ok := s.CredentialStore.(PolicyManager); ok {
+		if err := pm.UpdatePolicy(ctx, name, document); err != nil {
+			return err
+		}
+	} else {
+		if err := s.CredentialStore.PutPolicy(ctx, name, document); err != nil {
+			return err
+		}
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		content, err := json.Marshal(document)
+		if err != nil {
+			return err
+		}
+		_, err = client.PutPolicy(tx, &iam_pb.PutPolicyRequest{Name: name, Content: string(content)})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) CreateServiceAccount(ctx context.Context, sa *iam_pb.ServiceAccount) error {
+	glog.V(4).Infof("IAM: PropagatingCredentialStore.CreateServiceAccount %s (parent: %s)", sa.Id, sa.ParentUser)
+	if err := s.CredentialStore.CreateServiceAccount(ctx, sa); err != nil {
+		return err
+	}
+	// Fetch parent identity to propagate
+	identity, err := s.CredentialStore.GetUser(ctx, sa.ParentUser)
+	if err != nil {
+		glog.Warningf("failed to get parent user %s after creating service account: %v", sa.ParentUser, err)
+		return nil
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.PutIdentity(tx, &iam_pb.PutIdentityRequest{Identity: identity})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) UpdateServiceAccount(ctx context.Context, id string, sa *iam_pb.ServiceAccount) error {
+	if err := s.CredentialStore.UpdateServiceAccount(ctx, id, sa); err != nil {
+		return err
+	}
+	// Fetch parent identity to propagate
+	identity, err := s.CredentialStore.GetUser(ctx, sa.ParentUser)
+	if err != nil {
+		glog.Warningf("failed to get parent user %s after updating service account: %v", sa.ParentUser, err)
+		return nil
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.PutIdentity(tx, &iam_pb.PutIdentityRequest{Identity: identity})
+		return err
+	})
+	return nil
+}
+
+func (s *PropagatingCredentialStore) DeleteServiceAccount(ctx context.Context, id string) error {
+	// Retrieve SA first to get ParentUser
+	sa, err := s.CredentialStore.GetServiceAccount(ctx, id)
+	if err != nil {
+		// If accessing non-existent SA, just proceed to delete (idempotency)
+		// But we can't propagate to parent...
+		if err := s.CredentialStore.DeleteServiceAccount(ctx, id); err != nil {
+			return err
+		}
+		return nil
+	}
+
+	if err := s.CredentialStore.DeleteServiceAccount(ctx, id); err != nil {
+		return err
+	}
+
+	// Fetch parent identity to propagate
+	identity, err := s.CredentialStore.GetUser(ctx, sa.ParentUser)
+	if err != nil {
+		glog.Warningf("failed to get parent user %s after deleting service account: %v", sa.ParentUser, err)
+		return nil
+	}
+	s.propagateChange(ctx, func(tx context.Context, client s3_pb.SeaweedS3IamCacheClient) error {
+		_, err := client.PutIdentity(tx, &iam_pb.PutIdentityRequest{Identity: identity})
+		return err
+	})
+	return nil
+}
diff --git a/weed/pb/iam.proto b/weed/pb/iam.proto
index 4827262b2..4972ae108 100644
--- a/weed/pb/iam.proto
+++ b/weed/pb/iam.proto
@@ -290,3 +290,22 @@ message GetServiceAccountByAccessKeyResponse {
     ServiceAccount service_account = 1;
 }
 
+
+//////////////////////////////////////////////////
+// S3 IAM Cache Management
+// Designed for unidirectional propagation from Filer to S3 Servers
+
+
+message PutIdentityRequest {
+    Identity identity = 1;
+}
+
+message PutIdentityResponse {
+}
+
+message RemoveIdentityRequest {
+    string username = 1;
+}
+
+message RemoveIdentityResponse {
+}
diff --git a/weed/pb/iam_pb/iam.pb.go b/weed/pb/iam_pb/iam.pb.go
index 514d46660..243abda7e 100644
--- a/weed/pb/iam_pb/iam.pb.go
+++ b/weed/pb/iam_pb/iam.pb.go
@@ -2536,6 +2536,166 @@ func (x *GetServiceAccountByAccessKeyResponse) GetServiceAccount() *ServiceAccou
 	return nil
 }
 
+type PutIdentityRequest struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	Identity      *Identity              `protobuf:"bytes,1,opt,name=identity,proto3" json:"identity,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *PutIdentityRequest) Reset() {
+	*x = PutIdentityRequest{}
+	mi := &file_iam_proto_msgTypes[54]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *PutIdentityRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*PutIdentityRequest) ProtoMessage() {}
+
+func (x *PutIdentityRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_iam_proto_msgTypes[54]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use PutIdentityRequest.ProtoReflect.Descriptor instead.
+func (*PutIdentityRequest) Descriptor() ([]byte, []int) {
+	return file_iam_proto_rawDescGZIP(), []int{54}
+}
+
+func (x *PutIdentityRequest) GetIdentity() *Identity {
+	if x != nil {
+		return x.Identity
+	}
+	return nil
+}
+
+type PutIdentityResponse struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *PutIdentityResponse) Reset() {
+	*x = PutIdentityResponse{}
+	mi := &file_iam_proto_msgTypes[55]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *PutIdentityResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*PutIdentityResponse) ProtoMessage() {}
+
+func (x *PutIdentityResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_iam_proto_msgTypes[55]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use PutIdentityResponse.ProtoReflect.Descriptor instead.
+func (*PutIdentityResponse) Descriptor() ([]byte, []int) {
+	return file_iam_proto_rawDescGZIP(), []int{55}
+}
+
+type RemoveIdentityRequest struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	Username      string                 `protobuf:"bytes,1,opt,name=username,proto3" json:"username,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *RemoveIdentityRequest) Reset() {
+	*x = RemoveIdentityRequest{}
+	mi := &file_iam_proto_msgTypes[56]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *RemoveIdentityRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RemoveIdentityRequest) ProtoMessage() {}
+
+func (x *RemoveIdentityRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_iam_proto_msgTypes[56]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use RemoveIdentityRequest.ProtoReflect.Descriptor instead.
+func (*RemoveIdentityRequest) Descriptor() ([]byte, []int) {
+	return file_iam_proto_rawDescGZIP(), []int{56}
+}
+
+func (x *RemoveIdentityRequest) GetUsername() string {
+	if x != nil {
+		return x.Username
+	}
+	return ""
+}
+
+type RemoveIdentityResponse struct {
+	state         protoimpl.MessageState `protogen:"open.v1"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
+}
+
+func (x *RemoveIdentityResponse) Reset() {
+	*x = RemoveIdentityResponse{}
+	mi := &file_iam_proto_msgTypes[57]
+	ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+	ms.StoreMessageInfo(mi)
+}
+
+func (x *RemoveIdentityResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RemoveIdentityResponse) ProtoMessage() {}
+
+func (x *RemoveIdentityResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_iam_proto_msgTypes[57]
+	if x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use RemoveIdentityResponse.ProtoReflect.Descriptor instead.
+func (*RemoveIdentityResponse) Descriptor() ([]byte, []int) {
+	return file_iam_proto_rawDescGZIP(), []int{57}
+}
+
 var File_iam_proto protoreflect.FileDescriptor
 
 const file_iam_proto_rawDesc = "" +
@@ -2687,7 +2847,13 @@ const file_iam_proto_rawDesc = "" +
 	"\n" +
 	"access_key\x18\x01 \x01(\tR\taccessKey\"g\n" +
 	"$GetServiceAccountByAccessKeyResponse\x12?\n" +
-	"\x0fservice_account\x18\x01 \x01(\v2\x16.iam_pb.ServiceAccountR\x0eserviceAccount2\x99\r\n" +
+	"\x0fservice_account\x18\x01 \x01(\v2\x16.iam_pb.ServiceAccountR\x0eserviceAccount\"B\n" +
+	"\x12PutIdentityRequest\x12,\n" +
+	"\bidentity\x18\x01 \x01(\v2\x10.iam_pb.IdentityR\bidentity\"\x15\n" +
+	"\x13PutIdentityResponse\"3\n" +
+	"\x15RemoveIdentityRequest\x12\x1a\n" +
+	"\busername\x18\x01 \x01(\tR\busername\"\x18\n" +
+	"\x16RemoveIdentityResponse2\x99\r\n" +
 	"\x1fSeaweedIdentityAccessManagement\x12U\n" +
 	"\x10GetConfiguration\x12\x1f.iam_pb.GetConfigurationRequest\x1a .iam_pb.GetConfigurationResponse\x12U\n" +
 	"\x10PutConfiguration\x12\x1f.iam_pb.PutConfigurationRequest\x1a .iam_pb.PutConfigurationResponse\x12C\n" +
@@ -2726,7 +2892,7 @@ func file_iam_proto_rawDescGZIP() []byte {
 	return file_iam_proto_rawDescData
 }
 
-var file_iam_proto_msgTypes = make([]protoimpl.MessageInfo, 54)
+var file_iam_proto_msgTypes = make([]protoimpl.MessageInfo, 58)
 var file_iam_proto_goTypes = []any{
 	(*GetConfigurationRequest)(nil),              // 0: iam_pb.GetConfigurationRequest
 	(*GetConfigurationResponse)(nil),             // 1: iam_pb.GetConfigurationResponse
@@ -2782,6 +2948,10 @@ var file_iam_proto_goTypes = []any{
 	(*ListServiceAccountsResponse)(nil),          // 51: iam_pb.ListServiceAccountsResponse
 	(*GetServiceAccountByAccessKeyRequest)(nil),  // 52: iam_pb.GetServiceAccountByAccessKeyRequest
 	(*GetServiceAccountByAccessKeyResponse)(nil), // 53: iam_pb.GetServiceAccountByAccessKeyResponse
+	(*PutIdentityRequest)(nil),                   // 54: iam_pb.PutIdentityRequest
+	(*PutIdentityResponse)(nil),                  // 55: iam_pb.PutIdentityResponse
+	(*RemoveIdentityRequest)(nil),                // 56: iam_pb.RemoveIdentityRequest
+	(*RemoveIdentityResponse)(nil),               // 57: iam_pb.RemoveIdentityResponse
 }
 var file_iam_proto_depIdxs = []int32{
 	28, // 0: iam_pb.GetConfigurationResponse.configuration:type_name -> iam_pb.S3ApiConfiguration
@@ -2805,51 +2975,52 @@ var file_iam_proto_depIdxs = []int32{
 	32, // 18: iam_pb.GetServiceAccountResponse.service_account:type_name -> iam_pb.ServiceAccount
 	32, // 19: iam_pb.ListServiceAccountsResponse.service_accounts:type_name -> iam_pb.ServiceAccount
 	32, // 20: iam_pb.GetServiceAccountByAccessKeyResponse.service_account:type_name -> iam_pb.ServiceAccount
-	0,  // 21: iam_pb.SeaweedIdentityAccessManagement.GetConfiguration:input_type -> iam_pb.GetConfigurationRequest
-	2,  // 22: iam_pb.SeaweedIdentityAccessManagement.PutConfiguration:input_type -> iam_pb.PutConfigurationRequest
-	4,  // 23: iam_pb.SeaweedIdentityAccessManagement.CreateUser:input_type -> iam_pb.CreateUserRequest
-	6,  // 24: iam_pb.SeaweedIdentityAccessManagement.GetUser:input_type -> iam_pb.GetUserRequest
-	8,  // 25: iam_pb.SeaweedIdentityAccessManagement.UpdateUser:input_type -> iam_pb.UpdateUserRequest
-	10, // 26: iam_pb.SeaweedIdentityAccessManagement.DeleteUser:input_type -> iam_pb.DeleteUserRequest
-	12, // 27: iam_pb.SeaweedIdentityAccessManagement.ListUsers:input_type -> iam_pb.ListUsersRequest
-	14, // 28: iam_pb.SeaweedIdentityAccessManagement.CreateAccessKey:input_type -> iam_pb.CreateAccessKeyRequest
-	16, // 29: iam_pb.SeaweedIdentityAccessManagement.DeleteAccessKey:input_type -> iam_pb.DeleteAccessKeyRequest
-	18, // 30: iam_pb.SeaweedIdentityAccessManagement.GetUserByAccessKey:input_type -> iam_pb.GetUserByAccessKeyRequest
-	33, // 31: iam_pb.SeaweedIdentityAccessManagement.PutPolicy:input_type -> iam_pb.PutPolicyRequest
-	35, // 32: iam_pb.SeaweedIdentityAccessManagement.GetPolicy:input_type -> iam_pb.GetPolicyRequest
-	37, // 33: iam_pb.SeaweedIdentityAccessManagement.ListPolicies:input_type -> iam_pb.ListPoliciesRequest
-	39, // 34: iam_pb.SeaweedIdentityAccessManagement.DeletePolicy:input_type -> iam_pb.DeletePolicyRequest
-	42, // 35: iam_pb.SeaweedIdentityAccessManagement.CreateServiceAccount:input_type -> iam_pb.CreateServiceAccountRequest
-	44, // 36: iam_pb.SeaweedIdentityAccessManagement.UpdateServiceAccount:input_type -> iam_pb.UpdateServiceAccountRequest
-	46, // 37: iam_pb.SeaweedIdentityAccessManagement.DeleteServiceAccount:input_type -> iam_pb.DeleteServiceAccountRequest
-	48, // 38: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccount:input_type -> iam_pb.GetServiceAccountRequest
-	50, // 39: iam_pb.SeaweedIdentityAccessManagement.ListServiceAccounts:input_type -> iam_pb.ListServiceAccountsRequest
-	52, // 40: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccountByAccessKey:input_type -> iam_pb.GetServiceAccountByAccessKeyRequest
-	1,  // 41: iam_pb.SeaweedIdentityAccessManagement.GetConfiguration:output_type -> iam_pb.GetConfigurationResponse
-	3,  // 42: iam_pb.SeaweedIdentityAccessManagement.PutConfiguration:output_type -> iam_pb.PutConfigurationResponse
-	5,  // 43: iam_pb.SeaweedIdentityAccessManagement.CreateUser:output_type -> iam_pb.CreateUserResponse
-	7,  // 44: iam_pb.SeaweedIdentityAccessManagement.GetUser:output_type -> iam_pb.GetUserResponse
-	9,  // 45: iam_pb.SeaweedIdentityAccessManagement.UpdateUser:output_type -> iam_pb.UpdateUserResponse
-	11, // 46: iam_pb.SeaweedIdentityAccessManagement.DeleteUser:output_type -> iam_pb.DeleteUserResponse
-	13, // 47: iam_pb.SeaweedIdentityAccessManagement.ListUsers:output_type -> iam_pb.ListUsersResponse
-	15, // 48: iam_pb.SeaweedIdentityAccessManagement.CreateAccessKey:output_type -> iam_pb.CreateAccessKeyResponse
-	17, // 49: iam_pb.SeaweedIdentityAccessManagement.DeleteAccessKey:output_type -> iam_pb.DeleteAccessKeyResponse
-	19, // 50: iam_pb.SeaweedIdentityAccessManagement.GetUserByAccessKey:output_type -> iam_pb.GetUserByAccessKeyResponse
-	34, // 51: iam_pb.SeaweedIdentityAccessManagement.PutPolicy:output_type -> iam_pb.PutPolicyResponse
-	36, // 52: iam_pb.SeaweedIdentityAccessManagement.GetPolicy:output_type -> iam_pb.GetPolicyResponse
-	38, // 53: iam_pb.SeaweedIdentityAccessManagement.ListPolicies:output_type -> iam_pb.ListPoliciesResponse
-	40, // 54: iam_pb.SeaweedIdentityAccessManagement.DeletePolicy:output_type -> iam_pb.DeletePolicyResponse
-	43, // 55: iam_pb.SeaweedIdentityAccessManagement.CreateServiceAccount:output_type -> iam_pb.CreateServiceAccountResponse
-	45, // 56: iam_pb.SeaweedIdentityAccessManagement.UpdateServiceAccount:output_type -> iam_pb.UpdateServiceAccountResponse
-	47, // 57: iam_pb.SeaweedIdentityAccessManagement.DeleteServiceAccount:output_type -> iam_pb.DeleteServiceAccountResponse
-	49, // 58: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccount:output_type -> iam_pb.GetServiceAccountResponse
-	51, // 59: iam_pb.SeaweedIdentityAccessManagement.ListServiceAccounts:output_type -> iam_pb.ListServiceAccountsResponse
-	53, // 60: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccountByAccessKey:output_type -> iam_pb.GetServiceAccountByAccessKeyResponse
-	41, // [41:61] is the sub-list for method output_type
-	21, // [21:41] is the sub-list for method input_type
-	21, // [21:21] is the sub-list for extension type_name
-	21, // [21:21] is the sub-list for extension extendee
-	0,  // [0:21] is the sub-list for field type_name
+	29, // 21: iam_pb.PutIdentityRequest.identity:type_name -> iam_pb.Identity
+	0,  // 22: iam_pb.SeaweedIdentityAccessManagement.GetConfiguration:input_type -> iam_pb.GetConfigurationRequest
+	2,  // 23: iam_pb.SeaweedIdentityAccessManagement.PutConfiguration:input_type -> iam_pb.PutConfigurationRequest
+	4,  // 24: iam_pb.SeaweedIdentityAccessManagement.CreateUser:input_type -> iam_pb.CreateUserRequest
+	6,  // 25: iam_pb.SeaweedIdentityAccessManagement.GetUser:input_type -> iam_pb.GetUserRequest
+	8,  // 26: iam_pb.SeaweedIdentityAccessManagement.UpdateUser:input_type -> iam_pb.UpdateUserRequest
+	10, // 27: iam_pb.SeaweedIdentityAccessManagement.DeleteUser:input_type -> iam_pb.DeleteUserRequest
+	12, // 28: iam_pb.SeaweedIdentityAccessManagement.ListUsers:input_type -> iam_pb.ListUsersRequest
+	14, // 29: iam_pb.SeaweedIdentityAccessManagement.CreateAccessKey:input_type -> iam_pb.CreateAccessKeyRequest
+	16, // 30: iam_pb.SeaweedIdentityAccessManagement.DeleteAccessKey:input_type -> iam_pb.DeleteAccessKeyRequest
+	18, // 31: iam_pb.SeaweedIdentityAccessManagement.GetUserByAccessKey:input_type -> iam_pb.GetUserByAccessKeyRequest
+	33, // 32: iam_pb.SeaweedIdentityAccessManagement.PutPolicy:input_type -> iam_pb.PutPolicyRequest
+	35, // 33: iam_pb.SeaweedIdentityAccessManagement.GetPolicy:input_type -> iam_pb.GetPolicyRequest
+	37, // 34: iam_pb.SeaweedIdentityAccessManagement.ListPolicies:input_type -> iam_pb.ListPoliciesRequest
+	39, // 35: iam_pb.SeaweedIdentityAccessManagement.DeletePolicy:input_type -> iam_pb.DeletePolicyRequest
+	42, // 36: iam_pb.SeaweedIdentityAccessManagement.CreateServiceAccount:input_type -> iam_pb.CreateServiceAccountRequest
+	44, // 37: iam_pb.SeaweedIdentityAccessManagement.UpdateServiceAccount:input_type -> iam_pb.UpdateServiceAccountRequest
+	46, // 38: iam_pb.SeaweedIdentityAccessManagement.DeleteServiceAccount:input_type -> iam_pb.DeleteServiceAccountRequest
+	48, // 39: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccount:input_type -> iam_pb.GetServiceAccountRequest
+	50, // 40: iam_pb.SeaweedIdentityAccessManagement.ListServiceAccounts:input_type -> iam_pb.ListServiceAccountsRequest
+	52, // 41: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccountByAccessKey:input_type -> iam_pb.GetServiceAccountByAccessKeyRequest
+	1,  // 42: iam_pb.SeaweedIdentityAccessManagement.GetConfiguration:output_type -> iam_pb.GetConfigurationResponse
+	3,  // 43: iam_pb.SeaweedIdentityAccessManagement.PutConfiguration:output_type -> iam_pb.PutConfigurationResponse
+	5,  // 44: iam_pb.SeaweedIdentityAccessManagement.CreateUser:output_type -> iam_pb.CreateUserResponse
+	7,  // 45: iam_pb.SeaweedIdentityAccessManagement.GetUser:output_type -> iam_pb.GetUserResponse
+	9,  // 46: iam_pb.SeaweedIdentityAccessManagement.UpdateUser:output_type -> iam_pb.UpdateUserResponse
+	11, // 47: iam_pb.SeaweedIdentityAccessManagement.DeleteUser:output_type -> iam_pb.DeleteUserResponse
+	13, // 48: iam_pb.SeaweedIdentityAccessManagement.ListUsers:output_type -> iam_pb.ListUsersResponse
+	15, // 49: iam_pb.SeaweedIdentityAccessManagement.CreateAccessKey:output_type -> iam_pb.CreateAccessKeyResponse
+	17, // 50: iam_pb.SeaweedIdentityAccessManagement.DeleteAccessKey:output_type -> iam_pb.DeleteAccessKeyResponse
+	19, // 51: iam_pb.SeaweedIdentityAccessManagement.GetUserByAccessKey:output_type -> iam_pb.GetUserByAccessKeyResponse
+	34, // 52: iam_pb.SeaweedIdentityAccessManagement.PutPolicy:output_type -> iam_pb.PutPolicyResponse
+	36, // 53: iam_pb.SeaweedIdentityAccessManagement.GetPolicy:output_type -> iam_pb.GetPolicyResponse
+	38, // 54: iam_pb.SeaweedIdentityAccessManagement.ListPolicies:output_type -> iam_pb.ListPoliciesResponse
+	40, // 55: iam_pb.SeaweedIdentityAccessManagement.DeletePolicy:output_type -> iam_pb.DeletePolicyResponse
+	43, // 56: iam_pb.SeaweedIdentityAccessManagement.CreateServiceAccount:output_type -> iam_pb.CreateServiceAccountResponse
+	45, // 57: iam_pb.SeaweedIdentityAccessManagement.UpdateServiceAccount:output_type -> iam_pb.UpdateServiceAccountResponse
+	47, // 58: iam_pb.SeaweedIdentityAccessManagement.DeleteServiceAccount:output_type -> iam_pb.DeleteServiceAccountResponse
+	49, // 59: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccount:output_type -> iam_pb.GetServiceAccountResponse
+	51, // 60: iam_pb.SeaweedIdentityAccessManagement.ListServiceAccounts:output_type -> iam_pb.ListServiceAccountsResponse
+	53, // 61: iam_pb.SeaweedIdentityAccessManagement.GetServiceAccountByAccessKey:output_type -> iam_pb.GetServiceAccountByAccessKeyResponse
+	42, // [42:62] is the sub-list for method output_type
+	22, // [22:42] is the sub-list for method input_type
+	22, // [22:22] is the sub-list for extension type_name
+	22, // [22:22] is the sub-list for extension extendee
+	0,  // [0:22] is the sub-list for field type_name
 }
 
 func init() { file_iam_proto_init() }
@@ -2863,7 +3034,7 @@ func file_iam_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: unsafe.Slice(unsafe.StringData(file_iam_proto_rawDesc), len(file_iam_proto_rawDesc)),
 			NumEnums:      0,
-			NumMessages:   54,
+			NumMessages:   58,
 			NumExtensions: 0,
 			NumServices:   1,
 		},
diff --git a/weed/pb/s3.proto b/weed/pb/s3.proto
index 097c7ba26..8deb87ada 100644
--- a/weed/pb/s3.proto
+++ b/weed/pb/s3.proto
@@ -10,29 +10,14 @@ option java_outer_classname = "S3Proto";
 
 import "iam.proto";
 
-service SeaweedS3 {
-
-    // Explicit IAM APIs mirroring SeaweedIdentityAccessManagement
-    rpc ListUsers (iam_pb.ListUsersRequest) returns (iam_pb.ListUsersResponse) {}
-    rpc CreateUser (iam_pb.CreateUserRequest) returns (iam_pb.CreateUserResponse) {}
-    rpc GetUser (iam_pb.GetUserRequest) returns (iam_pb.GetUserResponse) {}
-    rpc UpdateUser (iam_pb.UpdateUserRequest) returns (iam_pb.UpdateUserResponse) {}
-    rpc DeleteUser (iam_pb.DeleteUserRequest) returns (iam_pb.DeleteUserResponse) {}
-    
-    rpc ListAccessKeys (iam_pb.ListAccessKeysRequest) returns (iam_pb.ListAccessKeysResponse) {}
-    rpc CreateAccessKey (iam_pb.CreateAccessKeyRequest) returns (iam_pb.CreateAccessKeyResponse) {}
-    rpc DeleteAccessKey (iam_pb.DeleteAccessKeyRequest) returns (iam_pb.DeleteAccessKeyResponse) {}
-    
-    rpc PutUserPolicy (iam_pb.PutUserPolicyRequest) returns (iam_pb.PutUserPolicyResponse) {}
-    rpc GetUserPolicy (iam_pb.GetUserPolicyRequest) returns (iam_pb.GetUserPolicyResponse) {}
-    rpc DeleteUserPolicy (iam_pb.DeleteUserPolicyRequest) returns (iam_pb.DeleteUserPolicyResponse) {}
-    
-    rpc ListServiceAccounts (iam_pb.ListServiceAccountsRequest) returns (iam_pb.ListServiceAccountsResponse) {}
-    rpc CreateServiceAccount (iam_pb.CreateServiceAccountRequest) returns (iam_pb.CreateServiceAccountResponse) {}
-    rpc UpdateServiceAccount (iam_pb.UpdateServiceAccountRequest) returns (iam_pb.UpdateServiceAccountResponse) {}
-    rpc DeleteServiceAccount (iam_pb.DeleteServiceAccountRequest) returns (iam_pb.DeleteServiceAccountResponse) {}
-    rpc GetServiceAccount (iam_pb.GetServiceAccountRequest) returns (iam_pb.GetServiceAccountResponse) {}
-
+// Designed for unidirectional propagation from Filer to S3 Servers
+service SeaweedS3IamCache {
+    rpc PutIdentity (iam_pb.PutIdentityRequest) returns (iam_pb.PutIdentityResponse);
+    rpc RemoveIdentity (iam_pb.RemoveIdentityRequest) returns (iam_pb.RemoveIdentityResponse);
+    rpc PutPolicy (iam_pb.PutPolicyRequest) returns (iam_pb.PutPolicyResponse);
+    rpc GetPolicy (iam_pb.GetPolicyRequest) returns (iam_pb.GetPolicyResponse);
+    rpc ListPolicies (iam_pb.ListPoliciesRequest) returns (iam_pb.ListPoliciesResponse);
+    rpc DeletePolicy (iam_pb.DeletePolicyRequest) returns (iam_pb.DeletePolicyResponse);
 }
 
 //////////////////////////////////////////////////
diff --git a/weed/pb/s3_pb/s3.pb.go b/weed/pb/s3_pb/s3.pb.go
index daf6fe912..308eaf95e 100644
--- a/weed/pb/s3_pb/s3.pb.go
+++ b/weed/pb/s3_pb/s3.pb.go
@@ -414,28 +414,14 @@ const file_s3_proto_rawDesc = "" +
 	"\rsse_algorithm\x18\x01 \x01(\tR\fsseAlgorithm\x12\x1c\n" +
 	"\n" +
 	"kms_key_id\x18\x02 \x01(\tR\bkmsKeyId\x12,\n" +
-	"\x12bucket_key_enabled\x18\x03 \x01(\bR\x10bucketKeyEnabled2\xc7\n" +
-	"\n" +
-	"\tSeaweedS3\x12B\n" +
-	"\tListUsers\x12\x18.iam_pb.ListUsersRequest\x1a\x19.iam_pb.ListUsersResponse\"\x00\x12E\n" +
-	"\n" +
-	"CreateUser\x12\x19.iam_pb.CreateUserRequest\x1a\x1a.iam_pb.CreateUserResponse\"\x00\x12<\n" +
-	"\aGetUser\x12\x16.iam_pb.GetUserRequest\x1a\x17.iam_pb.GetUserResponse\"\x00\x12E\n" +
-	"\n" +
-	"UpdateUser\x12\x19.iam_pb.UpdateUserRequest\x1a\x1a.iam_pb.UpdateUserResponse\"\x00\x12E\n" +
-	"\n" +
-	"DeleteUser\x12\x19.iam_pb.DeleteUserRequest\x1a\x1a.iam_pb.DeleteUserResponse\"\x00\x12Q\n" +
-	"\x0eListAccessKeys\x12\x1d.iam_pb.ListAccessKeysRequest\x1a\x1e.iam_pb.ListAccessKeysResponse\"\x00\x12T\n" +
-	"\x0fCreateAccessKey\x12\x1e.iam_pb.CreateAccessKeyRequest\x1a\x1f.iam_pb.CreateAccessKeyResponse\"\x00\x12T\n" +
-	"\x0fDeleteAccessKey\x12\x1e.iam_pb.DeleteAccessKeyRequest\x1a\x1f.iam_pb.DeleteAccessKeyResponse\"\x00\x12N\n" +
-	"\rPutUserPolicy\x12\x1c.iam_pb.PutUserPolicyRequest\x1a\x1d.iam_pb.PutUserPolicyResponse\"\x00\x12N\n" +
-	"\rGetUserPolicy\x12\x1c.iam_pb.GetUserPolicyRequest\x1a\x1d.iam_pb.GetUserPolicyResponse\"\x00\x12W\n" +
-	"\x10DeleteUserPolicy\x12\x1f.iam_pb.DeleteUserPolicyRequest\x1a .iam_pb.DeleteUserPolicyResponse\"\x00\x12`\n" +
-	"\x13ListServiceAccounts\x12\".iam_pb.ListServiceAccountsRequest\x1a#.iam_pb.ListServiceAccountsResponse\"\x00\x12c\n" +
-	"\x14CreateServiceAccount\x12#.iam_pb.CreateServiceAccountRequest\x1a$.iam_pb.CreateServiceAccountResponse\"\x00\x12c\n" +
-	"\x14UpdateServiceAccount\x12#.iam_pb.UpdateServiceAccountRequest\x1a$.iam_pb.UpdateServiceAccountResponse\"\x00\x12c\n" +
-	"\x14DeleteServiceAccount\x12#.iam_pb.DeleteServiceAccountRequest\x1a$.iam_pb.DeleteServiceAccountResponse\"\x00\x12Z\n" +
-	"\x11GetServiceAccount\x12 .iam_pb.GetServiceAccountRequest\x1a!.iam_pb.GetServiceAccountResponse\"\x00BI\n" +
+	"\x12bucket_key_enabled\x18\x03 \x01(\bR\x10bucketKeyEnabled2\xc6\x03\n" +
+	"\x11SeaweedS3IamCache\x12F\n" +
+	"\vPutIdentity\x12\x1a.iam_pb.PutIdentityRequest\x1a\x1b.iam_pb.PutIdentityResponse\x12O\n" +
+	"\x0eRemoveIdentity\x12\x1d.iam_pb.RemoveIdentityRequest\x1a\x1e.iam_pb.RemoveIdentityResponse\x12@\n" +
+	"\tPutPolicy\x12\x18.iam_pb.PutPolicyRequest\x1a\x19.iam_pb.PutPolicyResponse\x12@\n" +
+	"\tGetPolicy\x12\x18.iam_pb.GetPolicyRequest\x1a\x19.iam_pb.GetPolicyResponse\x12I\n" +
+	"\fListPolicies\x12\x1b.iam_pb.ListPoliciesRequest\x1a\x1c.iam_pb.ListPoliciesResponse\x12I\n" +
+	"\fDeletePolicy\x12\x1b.iam_pb.DeletePolicyRequest\x1a\x1c.iam_pb.DeletePolicyResponseBI\n" +
 	"\x10seaweedfs.clientB\aS3ProtoZ,github.com/seaweedfs/seaweedfs/weed/pb/s3_pbb\x06proto3"
 
 var (
@@ -452,47 +438,27 @@ func file_s3_proto_rawDescGZIP() []byte {
 
 var file_s3_proto_msgTypes = make([]protoimpl.MessageInfo, 9)
 var file_s3_proto_goTypes = []any{
-	(*S3CircuitBreakerConfig)(nil),              // 0: messaging_pb.S3CircuitBreakerConfig
-	(*S3CircuitBreakerOptions)(nil),             // 1: messaging_pb.S3CircuitBreakerOptions
-	(*CORSRule)(nil),                            // 2: messaging_pb.CORSRule
-	(*CORSConfiguration)(nil),                   // 3: messaging_pb.CORSConfiguration
-	(*BucketMetadata)(nil),                      // 4: messaging_pb.BucketMetadata
-	(*EncryptionConfiguration)(nil),             // 5: messaging_pb.EncryptionConfiguration
-	nil,                                         // 6: messaging_pb.S3CircuitBreakerConfig.BucketsEntry
-	nil,                                         // 7: messaging_pb.S3CircuitBreakerOptions.ActionsEntry
-	nil,                                         // 8: messaging_pb.BucketMetadata.TagsEntry
-	(*iam_pb.ListUsersRequest)(nil),             // 9: iam_pb.ListUsersRequest
-	(*iam_pb.CreateUserRequest)(nil),            // 10: iam_pb.CreateUserRequest
-	(*iam_pb.GetUserRequest)(nil),               // 11: iam_pb.GetUserRequest
-	(*iam_pb.UpdateUserRequest)(nil),            // 12: iam_pb.UpdateUserRequest
-	(*iam_pb.DeleteUserRequest)(nil),            // 13: iam_pb.DeleteUserRequest
-	(*iam_pb.ListAccessKeysRequest)(nil),        // 14: iam_pb.ListAccessKeysRequest
-	(*iam_pb.CreateAccessKeyRequest)(nil),       // 15: iam_pb.CreateAccessKeyRequest
-	(*iam_pb.DeleteAccessKeyRequest)(nil),       // 16: iam_pb.DeleteAccessKeyRequest
-	(*iam_pb.PutUserPolicyRequest)(nil),         // 17: iam_pb.PutUserPolicyRequest
-	(*iam_pb.GetUserPolicyRequest)(nil),         // 18: iam_pb.GetUserPolicyRequest
-	(*iam_pb.DeleteUserPolicyRequest)(nil),      // 19: iam_pb.DeleteUserPolicyRequest
-	(*iam_pb.ListServiceAccountsRequest)(nil),   // 20: iam_pb.ListServiceAccountsRequest
-	(*iam_pb.CreateServiceAccountRequest)(nil),  // 21: iam_pb.CreateServiceAccountRequest
-	(*iam_pb.UpdateServiceAccountRequest)(nil),  // 22: iam_pb.UpdateServiceAccountRequest
-	(*iam_pb.DeleteServiceAccountRequest)(nil),  // 23: iam_pb.DeleteServiceAccountRequest
-	(*iam_pb.GetServiceAccountRequest)(nil),     // 24: iam_pb.GetServiceAccountRequest
-	(*iam_pb.ListUsersResponse)(nil),            // 25: iam_pb.ListUsersResponse
-	(*iam_pb.CreateUserResponse)(nil),           // 26: iam_pb.CreateUserResponse
-	(*iam_pb.GetUserResponse)(nil),              // 27: iam_pb.GetUserResponse
-	(*iam_pb.UpdateUserResponse)(nil),           // 28: iam_pb.UpdateUserResponse
-	(*iam_pb.DeleteUserResponse)(nil),           // 29: iam_pb.DeleteUserResponse
-	(*iam_pb.ListAccessKeysResponse)(nil),       // 30: iam_pb.ListAccessKeysResponse
-	(*iam_pb.CreateAccessKeyResponse)(nil),      // 31: iam_pb.CreateAccessKeyResponse
-	(*iam_pb.DeleteAccessKeyResponse)(nil),      // 32: iam_pb.DeleteAccessKeyResponse
-	(*iam_pb.PutUserPolicyResponse)(nil),        // 33: iam_pb.PutUserPolicyResponse
-	(*iam_pb.GetUserPolicyResponse)(nil),        // 34: iam_pb.GetUserPolicyResponse
-	(*iam_pb.DeleteUserPolicyResponse)(nil),     // 35: iam_pb.DeleteUserPolicyResponse
-	(*iam_pb.ListServiceAccountsResponse)(nil),  // 36: iam_pb.ListServiceAccountsResponse
-	(*iam_pb.CreateServiceAccountResponse)(nil), // 37: iam_pb.CreateServiceAccountResponse
-	(*iam_pb.UpdateServiceAccountResponse)(nil), // 38: iam_pb.UpdateServiceAccountResponse
-	(*iam_pb.DeleteServiceAccountResponse)(nil), // 39: iam_pb.DeleteServiceAccountResponse
-	(*iam_pb.GetServiceAccountResponse)(nil),    // 40: iam_pb.GetServiceAccountResponse
+	(*S3CircuitBreakerConfig)(nil),        // 0: messaging_pb.S3CircuitBreakerConfig
+	(*S3CircuitBreakerOptions)(nil),       // 1: messaging_pb.S3CircuitBreakerOptions
+	(*CORSRule)(nil),                      // 2: messaging_pb.CORSRule
+	(*CORSConfiguration)(nil),             // 3: messaging_pb.CORSConfiguration
+	(*BucketMetadata)(nil),                // 4: messaging_pb.BucketMetadata
+	(*EncryptionConfiguration)(nil),       // 5: messaging_pb.EncryptionConfiguration
+	nil,                                   // 6: messaging_pb.S3CircuitBreakerConfig.BucketsEntry
+	nil,                                   // 7: messaging_pb.S3CircuitBreakerOptions.ActionsEntry
+	nil,                                   // 8: messaging_pb.BucketMetadata.TagsEntry
+	(*iam_pb.PutIdentityRequest)(nil),     // 9: iam_pb.PutIdentityRequest
+	(*iam_pb.RemoveIdentityRequest)(nil),  // 10: iam_pb.RemoveIdentityRequest
+	(*iam_pb.PutPolicyRequest)(nil),       // 11: iam_pb.PutPolicyRequest
+	(*iam_pb.GetPolicyRequest)(nil),       // 12: iam_pb.GetPolicyRequest
+	(*iam_pb.ListPoliciesRequest)(nil),    // 13: iam_pb.ListPoliciesRequest
+	(*iam_pb.DeletePolicyRequest)(nil),    // 14: iam_pb.DeletePolicyRequest
+	(*iam_pb.PutIdentityResponse)(nil),    // 15: iam_pb.PutIdentityResponse
+	(*iam_pb.RemoveIdentityResponse)(nil), // 16: iam_pb.RemoveIdentityResponse
+	(*iam_pb.PutPolicyResponse)(nil),      // 17: iam_pb.PutPolicyResponse
+	(*iam_pb.GetPolicyResponse)(nil),      // 18: iam_pb.GetPolicyResponse
+	(*iam_pb.ListPoliciesResponse)(nil),   // 19: iam_pb.ListPoliciesResponse
+	(*iam_pb.DeletePolicyResponse)(nil),   // 20: iam_pb.DeletePolicyResponse
 }
 var file_s3_proto_depIdxs = []int32{
 	1,  // 0: messaging_pb.S3CircuitBreakerConfig.global:type_name -> messaging_pb.S3CircuitBreakerOptions
@@ -503,40 +469,20 @@ var file_s3_proto_depIdxs = []int32{
 	3,  // 5: messaging_pb.BucketMetadata.cors:type_name -> messaging_pb.CORSConfiguration
 	5,  // 6: messaging_pb.BucketMetadata.encryption:type_name -> messaging_pb.EncryptionConfiguration
 	1,  // 7: messaging_pb.S3CircuitBreakerConfig.BucketsEntry.value:type_name -> messaging_pb.S3CircuitBreakerOptions
-	9,  // 8: messaging_pb.SeaweedS3.ListUsers:input_type -> iam_pb.ListUsersRequest
-	10, // 9: messaging_pb.SeaweedS3.CreateUser:input_type -> iam_pb.CreateUserRequest
-	11, // 10: messaging_pb.SeaweedS3.GetUser:input_type -> iam_pb.GetUserRequest
-	12, // 11: messaging_pb.SeaweedS3.UpdateUser:input_type -> iam_pb.UpdateUserRequest
-	13, // 12: messaging_pb.SeaweedS3.DeleteUser:input_type -> iam_pb.DeleteUserRequest
-	14, // 13: messaging_pb.SeaweedS3.ListAccessKeys:input_type -> iam_pb.ListAccessKeysRequest
-	15, // 14: messaging_pb.SeaweedS3.CreateAccessKey:input_type -> iam_pb.CreateAccessKeyRequest
-	16, // 15: messaging_pb.SeaweedS3.DeleteAccessKey:input_type -> iam_pb.DeleteAccessKeyRequest
-	17, // 16: messaging_pb.SeaweedS3.PutUserPolicy:input_type -> iam_pb.PutUserPolicyRequest
-	18, // 17: messaging_pb.SeaweedS3.GetUserPolicy:input_type -> iam_pb.GetUserPolicyRequest
-	19, // 18: messaging_pb.SeaweedS3.DeleteUserPolicy:input_type -> iam_pb.DeleteUserPolicyRequest
-	20, // 19: messaging_pb.SeaweedS3.ListServiceAccounts:input_type -> iam_pb.ListServiceAccountsRequest
-	21, // 20: messaging_pb.SeaweedS3.CreateServiceAccount:input_type -> iam_pb.CreateServiceAccountRequest
-	22, // 21: messaging_pb.SeaweedS3.UpdateServiceAccount:input_type -> iam_pb.UpdateServiceAccountRequest
-	23, // 22: messaging_pb.SeaweedS3.DeleteServiceAccount:input_type -> iam_pb.DeleteServiceAccountRequest
-	24, // 23: messaging_pb.SeaweedS3.GetServiceAccount:input_type -> iam_pb.GetServiceAccountRequest
-	25, // 24: messaging_pb.SeaweedS3.ListUsers:output_type -> iam_pb.ListUsersResponse
-	26, // 25: messaging_pb.SeaweedS3.CreateUser:output_type -> iam_pb.CreateUserResponse
-	27, // 26: messaging_pb.SeaweedS3.GetUser:output_type -> iam_pb.GetUserResponse
-	28, // 27: messaging_pb.SeaweedS3.UpdateUser:output_type -> iam_pb.UpdateUserResponse
-	29, // 28: messaging_pb.SeaweedS3.DeleteUser:output_type -> iam_pb.DeleteUserResponse
-	30, // 29: messaging_pb.SeaweedS3.ListAccessKeys:output_type -> iam_pb.ListAccessKeysResponse
-	31, // 30: messaging_pb.SeaweedS3.CreateAccessKey:output_type -> iam_pb.CreateAccessKeyResponse
-	32, // 31: messaging_pb.SeaweedS3.DeleteAccessKey:output_type -> iam_pb.DeleteAccessKeyResponse
-	33, // 32: messaging_pb.SeaweedS3.PutUserPolicy:output_type -> iam_pb.PutUserPolicyResponse
-	34, // 33: messaging_pb.SeaweedS3.GetUserPolicy:output_type -> iam_pb.GetUserPolicyResponse
-	35, // 34: messaging_pb.SeaweedS3.DeleteUserPolicy:output_type -> iam_pb.DeleteUserPolicyResponse
-	36, // 35: messaging_pb.SeaweedS3.ListServiceAccounts:output_type -> iam_pb.ListServiceAccountsResponse
-	37, // 36: messaging_pb.SeaweedS3.CreateServiceAccount:output_type -> iam_pb.CreateServiceAccountResponse
-	38, // 37: messaging_pb.SeaweedS3.UpdateServiceAccount:output_type -> iam_pb.UpdateServiceAccountResponse
-	39, // 38: messaging_pb.SeaweedS3.DeleteServiceAccount:output_type -> iam_pb.DeleteServiceAccountResponse
-	40, // 39: messaging_pb.SeaweedS3.GetServiceAccount:output_type -> iam_pb.GetServiceAccountResponse
-	24, // [24:40] is the sub-list for method output_type
-	8,  // [8:24] is the sub-list for method input_type
+	9,  // 8: messaging_pb.SeaweedS3IamCache.PutIdentity:input_type -> iam_pb.PutIdentityRequest
+	10, // 9: messaging_pb.SeaweedS3IamCache.RemoveIdentity:input_type -> iam_pb.RemoveIdentityRequest
+	11, // 10: messaging_pb.SeaweedS3IamCache.PutPolicy:input_type -> iam_pb.PutPolicyRequest
+	12, // 11: messaging_pb.SeaweedS3IamCache.GetPolicy:input_type -> iam_pb.GetPolicyRequest
+	13, // 12: messaging_pb.SeaweedS3IamCache.ListPolicies:input_type -> iam_pb.ListPoliciesRequest
+	14, // 13: messaging_pb.SeaweedS3IamCache.DeletePolicy:input_type -> iam_pb.DeletePolicyRequest
+	15, // 14: messaging_pb.SeaweedS3IamCache.PutIdentity:output_type -> iam_pb.PutIdentityResponse
+	16, // 15: messaging_pb.SeaweedS3IamCache.RemoveIdentity:output_type -> iam_pb.RemoveIdentityResponse
+	17, // 16: messaging_pb.SeaweedS3IamCache.PutPolicy:output_type -> iam_pb.PutPolicyResponse
+	18, // 17: messaging_pb.SeaweedS3IamCache.GetPolicy:output_type -> iam_pb.GetPolicyResponse
+	19, // 18: messaging_pb.SeaweedS3IamCache.ListPolicies:output_type -> iam_pb.ListPoliciesResponse
+	20, // 19: messaging_pb.SeaweedS3IamCache.DeletePolicy:output_type -> iam_pb.DeletePolicyResponse
+	14, // [14:20] is the sub-list for method output_type
+	8,  // [8:14] is the sub-list for method input_type
 	8,  // [8:8] is the sub-list for extension type_name
 	8,  // [8:8] is the sub-list for extension extendee
 	0,  // [0:8] is the sub-list for field type_name
diff --git a/weed/pb/s3_pb/s3_grpc.pb.go b/weed/pb/s3_pb/s3_grpc.pb.go
index 7a5bbbfcf..7e6b46b92 100644
--- a/weed/pb/s3_pb/s3_grpc.pb.go
+++ b/weed/pb/s3_pb/s3_grpc.pb.go
@@ -20,673 +20,295 @@ import (
 const _ = grpc.SupportPackageIsVersion9
 
 const (
-	SeaweedS3_ListUsers_FullMethodName            = "/messaging_pb.SeaweedS3/ListUsers"
-	SeaweedS3_CreateUser_FullMethodName           = "/messaging_pb.SeaweedS3/CreateUser"
-	SeaweedS3_GetUser_FullMethodName              = "/messaging_pb.SeaweedS3/GetUser"
-	SeaweedS3_UpdateUser_FullMethodName           = "/messaging_pb.SeaweedS3/UpdateUser"
-	SeaweedS3_DeleteUser_FullMethodName           = "/messaging_pb.SeaweedS3/DeleteUser"
-	SeaweedS3_ListAccessKeys_FullMethodName       = "/messaging_pb.SeaweedS3/ListAccessKeys"
-	SeaweedS3_CreateAccessKey_FullMethodName      = "/messaging_pb.SeaweedS3/CreateAccessKey"
-	SeaweedS3_DeleteAccessKey_FullMethodName      = "/messaging_pb.SeaweedS3/DeleteAccessKey"
-	SeaweedS3_PutUserPolicy_FullMethodName        = "/messaging_pb.SeaweedS3/PutUserPolicy"
-	SeaweedS3_GetUserPolicy_FullMethodName        = "/messaging_pb.SeaweedS3/GetUserPolicy"
-	SeaweedS3_DeleteUserPolicy_FullMethodName     = "/messaging_pb.SeaweedS3/DeleteUserPolicy"
-	SeaweedS3_ListServiceAccounts_FullMethodName  = "/messaging_pb.SeaweedS3/ListServiceAccounts"
-	SeaweedS3_CreateServiceAccount_FullMethodName = "/messaging_pb.SeaweedS3/CreateServiceAccount"
-	SeaweedS3_UpdateServiceAccount_FullMethodName = "/messaging_pb.SeaweedS3/UpdateServiceAccount"
-	SeaweedS3_DeleteServiceAccount_FullMethodName = "/messaging_pb.SeaweedS3/DeleteServiceAccount"
-	SeaweedS3_GetServiceAccount_FullMethodName    = "/messaging_pb.SeaweedS3/GetServiceAccount"
+	SeaweedS3IamCache_PutIdentity_FullMethodName    = "/messaging_pb.SeaweedS3IamCache/PutIdentity"
+	SeaweedS3IamCache_RemoveIdentity_FullMethodName = "/messaging_pb.SeaweedS3IamCache/RemoveIdentity"
+	SeaweedS3IamCache_PutPolicy_FullMethodName      = "/messaging_pb.SeaweedS3IamCache/PutPolicy"
+	SeaweedS3IamCache_GetPolicy_FullMethodName      = "/messaging_pb.SeaweedS3IamCache/GetPolicy"
+	SeaweedS3IamCache_ListPolicies_FullMethodName   = "/messaging_pb.SeaweedS3IamCache/ListPolicies"
+	SeaweedS3IamCache_DeletePolicy_FullMethodName   = "/messaging_pb.SeaweedS3IamCache/DeletePolicy"
 )
 
-// SeaweedS3Client is the client API for SeaweedS3 service.
+// SeaweedS3IamCacheClient is the client API for SeaweedS3IamCache service.
 //
 // For semantics around ctx use and closing/ending streaming RPCs, please refer to https://pkg.go.dev/google.golang.org/grpc/?tab=doc#ClientConn.NewStream.
-type SeaweedS3Client interface {
-	// Explicit IAM APIs mirroring SeaweedIdentityAccessManagement
-	ListUsers(ctx context.Context, in *iam_pb.ListUsersRequest, opts ...grpc.CallOption) (*iam_pb.ListUsersResponse, error)
-	CreateUser(ctx context.Context, in *iam_pb.CreateUserRequest, opts ...grpc.CallOption) (*iam_pb.CreateUserResponse, error)
-	GetUser(ctx context.Context, in *iam_pb.GetUserRequest, opts ...grpc.CallOption) (*iam_pb.GetUserResponse, error)
-	UpdateUser(ctx context.Context, in *iam_pb.UpdateUserRequest, opts ...grpc.CallOption) (*iam_pb.UpdateUserResponse, error)
-	DeleteUser(ctx context.Context, in *iam_pb.DeleteUserRequest, opts ...grpc.CallOption) (*iam_pb.DeleteUserResponse, error)
-	ListAccessKeys(ctx context.Context, in *iam_pb.ListAccessKeysRequest, opts ...grpc.CallOption) (*iam_pb.ListAccessKeysResponse, error)
-	CreateAccessKey(ctx context.Context, in *iam_pb.CreateAccessKeyRequest, opts ...grpc.CallOption) (*iam_pb.CreateAccessKeyResponse, error)
-	DeleteAccessKey(ctx context.Context, in *iam_pb.DeleteAccessKeyRequest, opts ...grpc.CallOption) (*iam_pb.DeleteAccessKeyResponse, error)
-	PutUserPolicy(ctx context.Context, in *iam_pb.PutUserPolicyRequest, opts ...grpc.CallOption) (*iam_pb.PutUserPolicyResponse, error)
-	GetUserPolicy(ctx context.Context, in *iam_pb.GetUserPolicyRequest, opts ...grpc.CallOption) (*iam_pb.GetUserPolicyResponse, error)
-	DeleteUserPolicy(ctx context.Context, in *iam_pb.DeleteUserPolicyRequest, opts ...grpc.CallOption) (*iam_pb.DeleteUserPolicyResponse, error)
-	ListServiceAccounts(ctx context.Context, in *iam_pb.ListServiceAccountsRequest, opts ...grpc.CallOption) (*iam_pb.ListServiceAccountsResponse, error)
-	CreateServiceAccount(ctx context.Context, in *iam_pb.CreateServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.CreateServiceAccountResponse, error)
-	UpdateServiceAccount(ctx context.Context, in *iam_pb.UpdateServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.UpdateServiceAccountResponse, error)
-	DeleteServiceAccount(ctx context.Context, in *iam_pb.DeleteServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.DeleteServiceAccountResponse, error)
-	GetServiceAccount(ctx context.Context, in *iam_pb.GetServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.GetServiceAccountResponse, error)
+//
+// Designed for unidirectional propagation from Filer to S3 Servers
+type SeaweedS3IamCacheClient interface {
+	PutIdentity(ctx context.Context, in *iam_pb.PutIdentityRequest, opts ...grpc.CallOption) (*iam_pb.PutIdentityResponse, error)
+	RemoveIdentity(ctx context.Context, in *iam_pb.RemoveIdentityRequest, opts ...grpc.CallOption) (*iam_pb.RemoveIdentityResponse, error)
+	PutPolicy(ctx context.Context, in *iam_pb.PutPolicyRequest, opts ...grpc.CallOption) (*iam_pb.PutPolicyResponse, error)
+	GetPolicy(ctx context.Context, in *iam_pb.GetPolicyRequest, opts ...grpc.CallOption) (*iam_pb.GetPolicyResponse, error)
+	ListPolicies(ctx context.Context, in *iam_pb.ListPoliciesRequest, opts ...grpc.CallOption) (*iam_pb.ListPoliciesResponse, error)
+	DeletePolicy(ctx context.Context, in *iam_pb.DeletePolicyRequest, opts ...grpc.CallOption) (*iam_pb.DeletePolicyResponse, error)
 }
 
-type seaweedS3Client struct {
+type seaweedS3IamCacheClient struct {
 	cc grpc.ClientConnInterface
 }
 
-func NewSeaweedS3Client(cc grpc.ClientConnInterface) SeaweedS3Client {
-	return &seaweedS3Client{cc}
-}
-
-func (c *seaweedS3Client) ListUsers(ctx context.Context, in *iam_pb.ListUsersRequest, opts ...grpc.CallOption) (*iam_pb.ListUsersResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.ListUsersResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_ListUsers_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) CreateUser(ctx context.Context, in *iam_pb.CreateUserRequest, opts ...grpc.CallOption) (*iam_pb.CreateUserResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.CreateUserResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_CreateUser_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) GetUser(ctx context.Context, in *iam_pb.GetUserRequest, opts ...grpc.CallOption) (*iam_pb.GetUserResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.GetUserResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_GetUser_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
+func NewSeaweedS3IamCacheClient(cc grpc.ClientConnInterface) SeaweedS3IamCacheClient {
+	return &seaweedS3IamCacheClient{cc}
 }
 
-func (c *seaweedS3Client) UpdateUser(ctx context.Context, in *iam_pb.UpdateUserRequest, opts ...grpc.CallOption) (*iam_pb.UpdateUserResponse, error) {
+func (c *seaweedS3IamCacheClient) PutIdentity(ctx context.Context, in *iam_pb.PutIdentityRequest, opts ...grpc.CallOption) (*iam_pb.PutIdentityResponse, error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.UpdateUserResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_UpdateUser_FullMethodName, in, out, cOpts...)
+	out := new(iam_pb.PutIdentityResponse)
+	err := c.cc.Invoke(ctx, SeaweedS3IamCache_PutIdentity_FullMethodName, in, out, cOpts...)
 	if err != nil {
 		return nil, err
 	}
 	return out, nil
 }
 
-func (c *seaweedS3Client) DeleteUser(ctx context.Context, in *iam_pb.DeleteUserRequest, opts ...grpc.CallOption) (*iam_pb.DeleteUserResponse, error) {
+func (c *seaweedS3IamCacheClient) RemoveIdentity(ctx context.Context, in *iam_pb.RemoveIdentityRequest, opts ...grpc.CallOption) (*iam_pb.RemoveIdentityResponse, error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.DeleteUserResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_DeleteUser_FullMethodName, in, out, cOpts...)
+	out := new(iam_pb.RemoveIdentityResponse)
+	err := c.cc.Invoke(ctx, SeaweedS3IamCache_RemoveIdentity_FullMethodName, in, out, cOpts...)
 	if err != nil {
 		return nil, err
 	}
 	return out, nil
 }
 
-func (c *seaweedS3Client) ListAccessKeys(ctx context.Context, in *iam_pb.ListAccessKeysRequest, opts ...grpc.CallOption) (*iam_pb.ListAccessKeysResponse, error) {
+func (c *seaweedS3IamCacheClient) PutPolicy(ctx context.Context, in *iam_pb.PutPolicyRequest, opts ...grpc.CallOption) (*iam_pb.PutPolicyResponse, error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.ListAccessKeysResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_ListAccessKeys_FullMethodName, in, out, cOpts...)
+	out := new(iam_pb.PutPolicyResponse)
+	err := c.cc.Invoke(ctx, SeaweedS3IamCache_PutPolicy_FullMethodName, in, out, cOpts...)
 	if err != nil {
 		return nil, err
 	}
 	return out, nil
 }
 
-func (c *seaweedS3Client) CreateAccessKey(ctx context.Context, in *iam_pb.CreateAccessKeyRequest, opts ...grpc.CallOption) (*iam_pb.CreateAccessKeyResponse, error) {
+func (c *seaweedS3IamCacheClient) GetPolicy(ctx context.Context, in *iam_pb.GetPolicyRequest, opts ...grpc.CallOption) (*iam_pb.GetPolicyResponse, error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.CreateAccessKeyResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_CreateAccessKey_FullMethodName, in, out, cOpts...)
+	out := new(iam_pb.GetPolicyResponse)
+	err := c.cc.Invoke(ctx, SeaweedS3IamCache_GetPolicy_FullMethodName, in, out, cOpts...)
 	if err != nil {
 		return nil, err
 	}
 	return out, nil
 }
 
-func (c *seaweedS3Client) DeleteAccessKey(ctx context.Context, in *iam_pb.DeleteAccessKeyRequest, opts ...grpc.CallOption) (*iam_pb.DeleteAccessKeyResponse, error) {
+func (c *seaweedS3IamCacheClient) ListPolicies(ctx context.Context, in *iam_pb.ListPoliciesRequest, opts ...grpc.CallOption) (*iam_pb.ListPoliciesResponse, error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.DeleteAccessKeyResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_DeleteAccessKey_FullMethodName, in, out, cOpts...)
+	out := new(iam_pb.ListPoliciesResponse)
+	err := c.cc.Invoke(ctx, SeaweedS3IamCache_ListPolicies_FullMethodName, in, out, cOpts...)
 	if err != nil {
 		return nil, err
 	}
 	return out, nil
 }
 
-func (c *seaweedS3Client) PutUserPolicy(ctx context.Context, in *iam_pb.PutUserPolicyRequest, opts ...grpc.CallOption) (*iam_pb.PutUserPolicyResponse, error) {
+func (c *seaweedS3IamCacheClient) DeletePolicy(ctx context.Context, in *iam_pb.DeletePolicyRequest, opts ...grpc.CallOption) (*iam_pb.DeletePolicyResponse, error) {
 	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.PutUserPolicyResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_PutUserPolicy_FullMethodName, in, out, cOpts...)
+	out := new(iam_pb.DeletePolicyResponse)
+	err := c.cc.Invoke(ctx, SeaweedS3IamCache_DeletePolicy_FullMethodName, in, out, cOpts...)
 	if err != nil {
 		return nil, err
 	}
 	return out, nil
 }
 
-func (c *seaweedS3Client) GetUserPolicy(ctx context.Context, in *iam_pb.GetUserPolicyRequest, opts ...grpc.CallOption) (*iam_pb.GetUserPolicyResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.GetUserPolicyResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_GetUserPolicy_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) DeleteUserPolicy(ctx context.Context, in *iam_pb.DeleteUserPolicyRequest, opts ...grpc.CallOption) (*iam_pb.DeleteUserPolicyResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.DeleteUserPolicyResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_DeleteUserPolicy_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) ListServiceAccounts(ctx context.Context, in *iam_pb.ListServiceAccountsRequest, opts ...grpc.CallOption) (*iam_pb.ListServiceAccountsResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.ListServiceAccountsResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_ListServiceAccounts_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) CreateServiceAccount(ctx context.Context, in *iam_pb.CreateServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.CreateServiceAccountResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.CreateServiceAccountResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_CreateServiceAccount_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) UpdateServiceAccount(ctx context.Context, in *iam_pb.UpdateServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.UpdateServiceAccountResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.UpdateServiceAccountResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_UpdateServiceAccount_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) DeleteServiceAccount(ctx context.Context, in *iam_pb.DeleteServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.DeleteServiceAccountResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.DeleteServiceAccountResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_DeleteServiceAccount_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-func (c *seaweedS3Client) GetServiceAccount(ctx context.Context, in *iam_pb.GetServiceAccountRequest, opts ...grpc.CallOption) (*iam_pb.GetServiceAccountResponse, error) {
-	cOpts := append([]grpc.CallOption{grpc.StaticMethod()}, opts...)
-	out := new(iam_pb.GetServiceAccountResponse)
-	err := c.cc.Invoke(ctx, SeaweedS3_GetServiceAccount_FullMethodName, in, out, cOpts...)
-	if err != nil {
-		return nil, err
-	}
-	return out, nil
-}
-
-// SeaweedS3Server is the server API for SeaweedS3 service.
-// All implementations must embed UnimplementedSeaweedS3Server
+// SeaweedS3IamCacheServer is the server API for SeaweedS3IamCache service.
+// All implementations must embed UnimplementedSeaweedS3IamCacheServer
 // for forward compatibility.
-type SeaweedS3Server interface {
-	// Explicit IAM APIs mirroring SeaweedIdentityAccessManagement
-	ListUsers(context.Context, *iam_pb.ListUsersRequest) (*iam_pb.ListUsersResponse, error)
-	CreateUser(context.Context, *iam_pb.CreateUserRequest) (*iam_pb.CreateUserResponse, error)
-	GetUser(context.Context, *iam_pb.GetUserRequest) (*iam_pb.GetUserResponse, error)
-	UpdateUser(context.Context, *iam_pb.UpdateUserRequest) (*iam_pb.UpdateUserResponse, error)
-	DeleteUser(context.Context, *iam_pb.DeleteUserRequest) (*iam_pb.DeleteUserResponse, error)
-	ListAccessKeys(context.Context, *iam_pb.ListAccessKeysRequest) (*iam_pb.ListAccessKeysResponse, error)
-	CreateAccessKey(context.Context, *iam_pb.CreateAccessKeyRequest) (*iam_pb.CreateAccessKeyResponse, error)
-	DeleteAccessKey(context.Context, *iam_pb.DeleteAccessKeyRequest) (*iam_pb.DeleteAccessKeyResponse, error)
-	PutUserPolicy(context.Context, *iam_pb.PutUserPolicyRequest) (*iam_pb.PutUserPolicyResponse, error)
-	GetUserPolicy(context.Context, *iam_pb.GetUserPolicyRequest) (*iam_pb.GetUserPolicyResponse, error)
-	DeleteUserPolicy(context.Context, *iam_pb.DeleteUserPolicyRequest) (*iam_pb.DeleteUserPolicyResponse, error)
-	ListServiceAccounts(context.Context, *iam_pb.ListServiceAccountsRequest) (*iam_pb.ListServiceAccountsResponse, error)
-	CreateServiceAccount(context.Context, *iam_pb.CreateServiceAccountRequest) (*iam_pb.CreateServiceAccountResponse, error)
-	UpdateServiceAccount(context.Context, *iam_pb.UpdateServiceAccountRequest) (*iam_pb.UpdateServiceAccountResponse, error)
-	DeleteServiceAccount(context.Context, *iam_pb.DeleteServiceAccountRequest) (*iam_pb.DeleteServiceAccountResponse, error)
-	GetServiceAccount(context.Context, *iam_pb.GetServiceAccountRequest) (*iam_pb.GetServiceAccountResponse, error)
-	mustEmbedUnimplementedSeaweedS3Server()
-}
-
-// UnimplementedSeaweedS3Server must be embedded to have
+//
+// Designed for unidirectional propagation from Filer to S3 Servers
+type SeaweedS3IamCacheServer interface {
+	PutIdentity(context.Context, *iam_pb.PutIdentityRequest) (*iam_pb.PutIdentityResponse, error)
+	RemoveIdentity(context.Context, *iam_pb.RemoveIdentityRequest) (*iam_pb.RemoveIdentityResponse, error)
+	PutPolicy(context.Context, *iam_pb.PutPolicyRequest) (*iam_pb.PutPolicyResponse, error)
+	GetPolicy(context.Context, *iam_pb.GetPolicyRequest) (*iam_pb.GetPolicyResponse, error)
+	ListPolicies(context.Context, *iam_pb.ListPoliciesRequest) (*iam_pb.ListPoliciesResponse, error)
+	DeletePolicy(context.Context, *iam_pb.DeletePolicyRequest) (*iam_pb.DeletePolicyResponse, error)
+	mustEmbedUnimplementedSeaweedS3IamCacheServer()
+}
+
+// UnimplementedSeaweedS3IamCacheServer must be embedded to have
 // forward compatible implementations.
 //
 // NOTE: this should be embedded by value instead of pointer to avoid a nil
 // pointer dereference when methods are called.
-type UnimplementedSeaweedS3Server struct{}
+type UnimplementedSeaweedS3IamCacheServer struct{}
 
-func (UnimplementedSeaweedS3Server) ListUsers(context.Context, *iam_pb.ListUsersRequest) (*iam_pb.ListUsersResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method ListUsers not implemented")
+func (UnimplementedSeaweedS3IamCacheServer) PutIdentity(context.Context, *iam_pb.PutIdentityRequest) (*iam_pb.PutIdentityResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method PutIdentity not implemented")
 }
-func (UnimplementedSeaweedS3Server) CreateUser(context.Context, *iam_pb.CreateUserRequest) (*iam_pb.CreateUserResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method CreateUser not implemented")
+func (UnimplementedSeaweedS3IamCacheServer) RemoveIdentity(context.Context, *iam_pb.RemoveIdentityRequest) (*iam_pb.RemoveIdentityResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method RemoveIdentity not implemented")
 }
-func (UnimplementedSeaweedS3Server) GetUser(context.Context, *iam_pb.GetUserRequest) (*iam_pb.GetUserResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method GetUser not implemented")
+func (UnimplementedSeaweedS3IamCacheServer) PutPolicy(context.Context, *iam_pb.PutPolicyRequest) (*iam_pb.PutPolicyResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method PutPolicy not implemented")
 }
-func (UnimplementedSeaweedS3Server) UpdateUser(context.Context, *iam_pb.UpdateUserRequest) (*iam_pb.UpdateUserResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method UpdateUser not implemented")
+func (UnimplementedSeaweedS3IamCacheServer) GetPolicy(context.Context, *iam_pb.GetPolicyRequest) (*iam_pb.GetPolicyResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method GetPolicy not implemented")
 }
-func (UnimplementedSeaweedS3Server) DeleteUser(context.Context, *iam_pb.DeleteUserRequest) (*iam_pb.DeleteUserResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method DeleteUser not implemented")
+func (UnimplementedSeaweedS3IamCacheServer) ListPolicies(context.Context, *iam_pb.ListPoliciesRequest) (*iam_pb.ListPoliciesResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method ListPolicies not implemented")
 }
-func (UnimplementedSeaweedS3Server) ListAccessKeys(context.Context, *iam_pb.ListAccessKeysRequest) (*iam_pb.ListAccessKeysResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method ListAccessKeys not implemented")
+func (UnimplementedSeaweedS3IamCacheServer) DeletePolicy(context.Context, *iam_pb.DeletePolicyRequest) (*iam_pb.DeletePolicyResponse, error) {
+	return nil, status.Errorf(codes.Unimplemented, "method DeletePolicy not implemented")
 }
-func (UnimplementedSeaweedS3Server) CreateAccessKey(context.Context, *iam_pb.CreateAccessKeyRequest) (*iam_pb.CreateAccessKeyResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method CreateAccessKey not implemented")
-}
-func (UnimplementedSeaweedS3Server) DeleteAccessKey(context.Context, *iam_pb.DeleteAccessKeyRequest) (*iam_pb.DeleteAccessKeyResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method DeleteAccessKey not implemented")
-}
-func (UnimplementedSeaweedS3Server) PutUserPolicy(context.Context, *iam_pb.PutUserPolicyRequest) (*iam_pb.PutUserPolicyResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method PutUserPolicy not implemented")
-}
-func (UnimplementedSeaweedS3Server) GetUserPolicy(context.Context, *iam_pb.GetUserPolicyRequest) (*iam_pb.GetUserPolicyResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method GetUserPolicy not implemented")
-}
-func (UnimplementedSeaweedS3Server) DeleteUserPolicy(context.Context, *iam_pb.DeleteUserPolicyRequest) (*iam_pb.DeleteUserPolicyResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method DeleteUserPolicy not implemented")
-}
-func (UnimplementedSeaweedS3Server) ListServiceAccounts(context.Context, *iam_pb.ListServiceAccountsRequest) (*iam_pb.ListServiceAccountsResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method ListServiceAccounts not implemented")
-}
-func (UnimplementedSeaweedS3Server) CreateServiceAccount(context.Context, *iam_pb.CreateServiceAccountRequest) (*iam_pb.CreateServiceAccountResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method CreateServiceAccount not implemented")
-}
-func (UnimplementedSeaweedS3Server) UpdateServiceAccount(context.Context, *iam_pb.UpdateServiceAccountRequest) (*iam_pb.UpdateServiceAccountResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method UpdateServiceAccount not implemented")
-}
-func (UnimplementedSeaweedS3Server) DeleteServiceAccount(context.Context, *iam_pb.DeleteServiceAccountRequest) (*iam_pb.DeleteServiceAccountResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method DeleteServiceAccount not implemented")
-}
-func (UnimplementedSeaweedS3Server) GetServiceAccount(context.Context, *iam_pb.GetServiceAccountRequest) (*iam_pb.GetServiceAccountResponse, error) {
-	return nil, status.Errorf(codes.Unimplemented, "method GetServiceAccount not implemented")
-}
-func (UnimplementedSeaweedS3Server) mustEmbedUnimplementedSeaweedS3Server() {}
-func (UnimplementedSeaweedS3Server) testEmbeddedByValue()                   {}
+func (UnimplementedSeaweedS3IamCacheServer) mustEmbedUnimplementedSeaweedS3IamCacheServer() {}
+func (UnimplementedSeaweedS3IamCacheServer) testEmbeddedByValue()                           {}
 
-// UnsafeSeaweedS3Server may be embedded to opt out of forward compatibility for this service.
-// Use of this interface is not recommended, as added methods to SeaweedS3Server will
+// UnsafeSeaweedS3IamCacheServer may be embedded to opt out of forward compatibility for this service.
+// Use of this interface is not recommended, as added methods to SeaweedS3IamCacheServer will
 // result in compilation errors.
-type UnsafeSeaweedS3Server interface {
-	mustEmbedUnimplementedSeaweedS3Server()
+type UnsafeSeaweedS3IamCacheServer interface {
+	mustEmbedUnimplementedSeaweedS3IamCacheServer()
 }
 
-func RegisterSeaweedS3Server(s grpc.ServiceRegistrar, srv SeaweedS3Server) {
-	// If the following call pancis, it indicates UnimplementedSeaweedS3Server was
+func RegisterSeaweedS3IamCacheServer(s grpc.ServiceRegistrar, srv SeaweedS3IamCacheServer) {
+	// If the following call pancis, it indicates UnimplementedSeaweedS3IamCacheServer was
 	// embedded by pointer and is nil.  This will cause panics if an
 	// unimplemented method is ever invoked, so we test this at initialization
 	// time to prevent it from happening at runtime later due to I/O.
 	if t, ok := srv.(interface{ testEmbeddedByValue() }); ok {
 		t.testEmbeddedByValue()
 	}
-	s.RegisterService(&SeaweedS3_ServiceDesc, srv)
-}
-
-func _SeaweedS3_ListUsers_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.ListUsersRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).ListUsers(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_ListUsers_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).ListUsers(ctx, req.(*iam_pb.ListUsersRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_CreateUser_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.CreateUserRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).CreateUser(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_CreateUser_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).CreateUser(ctx, req.(*iam_pb.CreateUserRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_GetUser_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.GetUserRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).GetUser(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_GetUser_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).GetUser(ctx, req.(*iam_pb.GetUserRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_UpdateUser_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.UpdateUserRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).UpdateUser(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_UpdateUser_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).UpdateUser(ctx, req.(*iam_pb.UpdateUserRequest))
-	}
-	return interceptor(ctx, in, info, handler)
+	s.RegisterService(&SeaweedS3IamCache_ServiceDesc, srv)
 }
 
-func _SeaweedS3_DeleteUser_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.DeleteUserRequest)
+func _SeaweedS3IamCache_PutIdentity_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(iam_pb.PutIdentityRequest)
 	if err := dec(in); err != nil {
 		return nil, err
 	}
 	if interceptor == nil {
-		return srv.(SeaweedS3Server).DeleteUser(ctx, in)
+		return srv.(SeaweedS3IamCacheServer).PutIdentity(ctx, in)
 	}
 	info := &grpc.UnaryServerInfo{
 		Server:     srv,
-		FullMethod: SeaweedS3_DeleteUser_FullMethodName,
+		FullMethod: SeaweedS3IamCache_PutIdentity_FullMethodName,
 	}
 	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).DeleteUser(ctx, req.(*iam_pb.DeleteUserRequest))
+		return srv.(SeaweedS3IamCacheServer).PutIdentity(ctx, req.(*iam_pb.PutIdentityRequest))
 	}
 	return interceptor(ctx, in, info, handler)
 }
 
-func _SeaweedS3_ListAccessKeys_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.ListAccessKeysRequest)
+func _SeaweedS3IamCache_RemoveIdentity_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(iam_pb.RemoveIdentityRequest)
 	if err := dec(in); err != nil {
 		return nil, err
 	}
 	if interceptor == nil {
-		return srv.(SeaweedS3Server).ListAccessKeys(ctx, in)
+		return srv.(SeaweedS3IamCacheServer).RemoveIdentity(ctx, in)
 	}
 	info := &grpc.UnaryServerInfo{
 		Server:     srv,
-		FullMethod: SeaweedS3_ListAccessKeys_FullMethodName,
+		FullMethod: SeaweedS3IamCache_RemoveIdentity_FullMethodName,
 	}
 	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).ListAccessKeys(ctx, req.(*iam_pb.ListAccessKeysRequest))
+		return srv.(SeaweedS3IamCacheServer).RemoveIdentity(ctx, req.(*iam_pb.RemoveIdentityRequest))
 	}
 	return interceptor(ctx, in, info, handler)
 }
 
-func _SeaweedS3_CreateAccessKey_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.CreateAccessKeyRequest)
+func _SeaweedS3IamCache_PutPolicy_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(iam_pb.PutPolicyRequest)
 	if err := dec(in); err != nil {
 		return nil, err
 	}
 	if interceptor == nil {
-		return srv.(SeaweedS3Server).CreateAccessKey(ctx, in)
+		return srv.(SeaweedS3IamCacheServer).PutPolicy(ctx, in)
 	}
 	info := &grpc.UnaryServerInfo{
 		Server:     srv,
-		FullMethod: SeaweedS3_CreateAccessKey_FullMethodName,
+		FullMethod: SeaweedS3IamCache_PutPolicy_FullMethodName,
 	}
 	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).CreateAccessKey(ctx, req.(*iam_pb.CreateAccessKeyRequest))
+		return srv.(SeaweedS3IamCacheServer).PutPolicy(ctx, req.(*iam_pb.PutPolicyRequest))
 	}
 	return interceptor(ctx, in, info, handler)
 }
 
-func _SeaweedS3_DeleteAccessKey_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.DeleteAccessKeyRequest)
+func _SeaweedS3IamCache_GetPolicy_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(iam_pb.GetPolicyRequest)
 	if err := dec(in); err != nil {
 		return nil, err
 	}
 	if interceptor == nil {
-		return srv.(SeaweedS3Server).DeleteAccessKey(ctx, in)
+		return srv.(SeaweedS3IamCacheServer).GetPolicy(ctx, in)
 	}
 	info := &grpc.UnaryServerInfo{
 		Server:     srv,
-		FullMethod: SeaweedS3_DeleteAccessKey_FullMethodName,
+		FullMethod: SeaweedS3IamCache_GetPolicy_FullMethodName,
 	}
 	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).DeleteAccessKey(ctx, req.(*iam_pb.DeleteAccessKeyRequest))
+		return srv.(SeaweedS3IamCacheServer).GetPolicy(ctx, req.(*iam_pb.GetPolicyRequest))
 	}
 	return interceptor(ctx, in, info, handler)
 }
 
-func _SeaweedS3_PutUserPolicy_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.PutUserPolicyRequest)
+func _SeaweedS3IamCache_ListPolicies_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(iam_pb.ListPoliciesRequest)
 	if err := dec(in); err != nil {
 		return nil, err
 	}
 	if interceptor == nil {
-		return srv.(SeaweedS3Server).PutUserPolicy(ctx, in)
+		return srv.(SeaweedS3IamCacheServer).ListPolicies(ctx, in)
 	}
 	info := &grpc.UnaryServerInfo{
 		Server:     srv,
-		FullMethod: SeaweedS3_PutUserPolicy_FullMethodName,
+		FullMethod: SeaweedS3IamCache_ListPolicies_FullMethodName,
 	}
 	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).PutUserPolicy(ctx, req.(*iam_pb.PutUserPolicyRequest))
+		return srv.(SeaweedS3IamCacheServer).ListPolicies(ctx, req.(*iam_pb.ListPoliciesRequest))
 	}
 	return interceptor(ctx, in, info, handler)
 }
 
-func _SeaweedS3_GetUserPolicy_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.GetUserPolicyRequest)
+func _SeaweedS3IamCache_DeletePolicy_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
+	in := new(iam_pb.DeletePolicyRequest)
 	if err := dec(in); err != nil {
 		return nil, err
 	}
 	if interceptor == nil {
-		return srv.(SeaweedS3Server).GetUserPolicy(ctx, in)
+		return srv.(SeaweedS3IamCacheServer).DeletePolicy(ctx, in)
 	}
 	info := &grpc.UnaryServerInfo{
 		Server:     srv,
-		FullMethod: SeaweedS3_GetUserPolicy_FullMethodName,
+		FullMethod: SeaweedS3IamCache_DeletePolicy_FullMethodName,
 	}
 	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).GetUserPolicy(ctx, req.(*iam_pb.GetUserPolicyRequest))
+		return srv.(SeaweedS3IamCacheServer).DeletePolicy(ctx, req.(*iam_pb.DeletePolicyRequest))
 	}
 	return interceptor(ctx, in, info, handler)
 }
 
-func _SeaweedS3_DeleteUserPolicy_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.DeleteUserPolicyRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).DeleteUserPolicy(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_DeleteUserPolicy_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).DeleteUserPolicy(ctx, req.(*iam_pb.DeleteUserPolicyRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_ListServiceAccounts_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.ListServiceAccountsRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).ListServiceAccounts(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_ListServiceAccounts_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).ListServiceAccounts(ctx, req.(*iam_pb.ListServiceAccountsRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_CreateServiceAccount_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.CreateServiceAccountRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).CreateServiceAccount(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_CreateServiceAccount_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).CreateServiceAccount(ctx, req.(*iam_pb.CreateServiceAccountRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_UpdateServiceAccount_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.UpdateServiceAccountRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).UpdateServiceAccount(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_UpdateServiceAccount_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).UpdateServiceAccount(ctx, req.(*iam_pb.UpdateServiceAccountRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_DeleteServiceAccount_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.DeleteServiceAccountRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).DeleteServiceAccount(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_DeleteServiceAccount_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).DeleteServiceAccount(ctx, req.(*iam_pb.DeleteServiceAccountRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-func _SeaweedS3_GetServiceAccount_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {
-	in := new(iam_pb.GetServiceAccountRequest)
-	if err := dec(in); err != nil {
-		return nil, err
-	}
-	if interceptor == nil {
-		return srv.(SeaweedS3Server).GetServiceAccount(ctx, in)
-	}
-	info := &grpc.UnaryServerInfo{
-		Server:     srv,
-		FullMethod: SeaweedS3_GetServiceAccount_FullMethodName,
-	}
-	handler := func(ctx context.Context, req interface{}) (interface{}, error) {
-		return srv.(SeaweedS3Server).GetServiceAccount(ctx, req.(*iam_pb.GetServiceAccountRequest))
-	}
-	return interceptor(ctx, in, info, handler)
-}
-
-// SeaweedS3_ServiceDesc is the grpc.ServiceDesc for SeaweedS3 service.
+// SeaweedS3IamCache_ServiceDesc is the grpc.ServiceDesc for SeaweedS3IamCache service.
 // It's only intended for direct use with grpc.RegisterService,
 // and not to be introspected or modified (even as a copy)
-var SeaweedS3_ServiceDesc = grpc.ServiceDesc{
-	ServiceName: "messaging_pb.SeaweedS3",
-	HandlerType: (*SeaweedS3Server)(nil),
+var SeaweedS3IamCache_ServiceDesc = grpc.ServiceDesc{
+	ServiceName: "messaging_pb.SeaweedS3IamCache",
+	HandlerType: (*SeaweedS3IamCacheServer)(nil),
 	Methods: []grpc.MethodDesc{
 		{
-			MethodName: "ListUsers",
-			Handler:    _SeaweedS3_ListUsers_Handler,
-		},
-		{
-			MethodName: "CreateUser",
-			Handler:    _SeaweedS3_CreateUser_Handler,
-		},
-		{
-			MethodName: "GetUser",
-			Handler:    _SeaweedS3_GetUser_Handler,
-		},
-		{
-			MethodName: "UpdateUser",
-			Handler:    _SeaweedS3_UpdateUser_Handler,
-		},
-		{
-			MethodName: "DeleteUser",
-			Handler:    _SeaweedS3_DeleteUser_Handler,
-		},
-		{
-			MethodName: "ListAccessKeys",
-			Handler:    _SeaweedS3_ListAccessKeys_Handler,
-		},
-		{
-			MethodName: "CreateAccessKey",
-			Handler:    _SeaweedS3_CreateAccessKey_Handler,
-		},
-		{
-			MethodName: "DeleteAccessKey",
-			Handler:    _SeaweedS3_DeleteAccessKey_Handler,
-		},
-		{
-			MethodName: "PutUserPolicy",
-			Handler:    _SeaweedS3_PutUserPolicy_Handler,
-		},
-		{
-			MethodName: "GetUserPolicy",
-			Handler:    _SeaweedS3_GetUserPolicy_Handler,
-		},
-		{
-			MethodName: "DeleteUserPolicy",
-			Handler:    _SeaweedS3_DeleteUserPolicy_Handler,
+			MethodName: "PutIdentity",
+			Handler:    _SeaweedS3IamCache_PutIdentity_Handler,
 		},
 		{
-			MethodName: "ListServiceAccounts",
-			Handler:    _SeaweedS3_ListServiceAccounts_Handler,
+			MethodName: "RemoveIdentity",
+			Handler:    _SeaweedS3IamCache_RemoveIdentity_Handler,
 		},
 		{
-			MethodName: "CreateServiceAccount",
-			Handler:    _SeaweedS3_CreateServiceAccount_Handler,
+			MethodName: "PutPolicy",
+			Handler:    _SeaweedS3IamCache_PutPolicy_Handler,
 		},
 		{
-			MethodName: "UpdateServiceAccount",
-			Handler:    _SeaweedS3_UpdateServiceAccount_Handler,
+			MethodName: "GetPolicy",
+			Handler:    _SeaweedS3IamCache_GetPolicy_Handler,
 		},
 		{
-			MethodName: "DeleteServiceAccount",
-			Handler:    _SeaweedS3_DeleteServiceAccount_Handler,
+			MethodName: "ListPolicies",
+			Handler:    _SeaweedS3IamCache_ListPolicies_Handler,
 		},
 		{
-			MethodName: "GetServiceAccount",
-			Handler:    _SeaweedS3_GetServiceAccount_Handler,
+			MethodName: "DeletePolicy",
+			Handler:    _SeaweedS3IamCache_DeletePolicy_Handler,
 		},
 	},
 	Streams:  []grpc.StreamDesc{},
diff --git a/weed/s3api/auth_credentials.go b/weed/s3api/auth_credentials.go
index 97a7a8a37..3e10396f1 100644
--- a/weed/s3api/auth_credentials.go
+++ b/weed/s3api/auth_credentials.go
@@ -44,6 +44,7 @@ type IdentityAccessManagement struct {
 	identities        []*Identity
 	accessKeyIdent    map[string]*Identity
 	nameToIdentity    map[string]*Identity // O(1) lookup by identity name
+	policies          map[string]*iam_pb.Policy
 	accounts          map[string]*Account
 	emailAccount      map[string]*Account
 	hashes            map[string]*sync.Pool
@@ -83,6 +84,7 @@ type Identity struct {
 	PrincipalArn string                 // ARN for IAM authorization (e.g., "arn:aws:iam::account-id:user/username")
 	Disabled     bool                   // User status: false = enabled (default), true = disabled
 	Claims       map[string]interface{} // JWT claims for policy substitution
+	IsStatic     bool                   // Whether identity was loaded from static config (immutable)
 }
 
 // Account represents a system user, a system user can
@@ -187,6 +189,7 @@ func NewIdentityAccessManagementWithStore(option *S3ApiServerOption, explicitSto
 		iam.staticIdentityNames = make(map[string]bool)
 		for _, identity := range iam.identities {
 			iam.staticIdentityNames[identity.Name] = true
+			identity.IsStatic = true
 		}
 		iam.m.Unlock()
 	}
@@ -294,6 +297,7 @@ func (iam *IdentityAccessManagement) loadEnvironmentVariableCredentials() {
 		Actions: []Action{
 			s3_constants.ACTION_ADMIN,
 		},
+		IsStatic: true,
 	}
 
 	iam.m.Lock()
@@ -407,19 +411,20 @@ func (iam *IdentityAccessManagement) loadS3ApiConfiguration(config *iam_pb.S3Api
 
 	if hasStaticConfig {
 		// Merge mode: preserve static identities, add/update dynamic ones
-		return iam.mergeS3ApiConfiguration(config)
+		return iam.MergeS3ApiConfiguration(config)
 	}
 
 	// Normal mode: completely replace configuration
-	return iam.replaceS3ApiConfiguration(config)
+	return iam.ReplaceS3ApiConfiguration(config)
 }
 
-// replaceS3ApiConfiguration completely replaces the current configuration (used when no static config)
-func (iam *IdentityAccessManagement) replaceS3ApiConfiguration(config *iam_pb.S3ApiConfiguration) error {
+// ReplaceS3ApiConfiguration completely replaces the current configuration (used when no static config)
+func (iam *IdentityAccessManagement) ReplaceS3ApiConfiguration(config *iam_pb.S3ApiConfiguration) error {
 	var identities []*Identity
 	var identityAnonymous *Identity
 	accessKeyIdent := make(map[string]*Identity)
 	nameToIdentity := make(map[string]*Identity)
+	policies := make(map[string]*iam_pb.Policy)
 	accounts := make(map[string]*Account)
 	emailAccount := make(map[string]*Account)
 	foundAccountAdmin := false
@@ -458,6 +463,9 @@ func (iam *IdentityAccessManagement) replaceS3ApiConfiguration(config *iam_pb.S3
 		}
 		emailAccount[AccountAnonymous.EmailAddress] = accounts[AccountAnonymous.Id]
 	}
+	for _, policy := range config.Policies {
+		policies[policy.Name] = policy
+	}
 	for _, ident := range config.Identities {
 		glog.V(3).Infof("loading identity %s (disabled=%v)", ident.Name, ident.Disabled)
 		t := &Identity{
@@ -537,6 +545,7 @@ func (iam *IdentityAccessManagement) replaceS3ApiConfiguration(config *iam_pb.S3
 	iam.emailAccount = emailAccount
 	iam.accessKeyIdent = accessKeyIdent
 	iam.nameToIdentity = nameToIdentity
+	iam.policies = policies
 	// Update authentication state based on whether identities exist
 	// Once enabled, keep it enabled (one-way toggle)
 	authJustEnabled := iam.updateAuthenticationState(len(identities))
@@ -566,10 +575,10 @@ func (iam *IdentityAccessManagement) replaceS3ApiConfiguration(config *iam_pb.S3
 	return nil
 }
 
-// mergeS3ApiConfiguration merges dynamic configuration with existing static configuration
+// MergeS3ApiConfiguration merges dynamic configuration with existing static configuration
 // Static identities (from file) are preserved and cannot be updated
 // Dynamic identities (from filer/admin) can be added or updated
-func (iam *IdentityAccessManagement) mergeS3ApiConfiguration(config *iam_pb.S3ApiConfiguration) error {
+func (iam *IdentityAccessManagement) MergeS3ApiConfiguration(config *iam_pb.S3ApiConfiguration) error {
 	// Start with current configuration (which includes static identities)
 	iam.m.RLock()
 	identities := make([]*Identity, len(iam.identities))
@@ -583,6 +592,10 @@ func (iam *IdentityAccessManagement) mergeS3ApiConfiguration(config *iam_pb.S3Ap
 	for k, v := range iam.nameToIdentity {
 		nameToIdentity[k] = v
 	}
+	policies := make(map[string]*iam_pb.Policy)
+	for k, v := range iam.policies {
+		policies[k] = v
+	}
 	accounts := make(map[string]*Account)
 	for k, v := range iam.accounts {
 		accounts[k] = v
@@ -755,6 +768,10 @@ func (iam *IdentityAccessManagement) mergeS3ApiConfiguration(config *iam_pb.S3Ap
 		glog.V(3).Infof("Loaded service account %s for dynamic parent %s (expiration: %d)", sa.Id, sa.ParentUser, sa.Expiration)
 	}
 
+	for _, policy := range config.Policies {
+		policies[policy.Name] = policy
+	}
+
 	iam.m.Lock()
 	// atomically switch
 	iam.identities = identities
@@ -763,6 +780,7 @@ func (iam *IdentityAccessManagement) mergeS3ApiConfiguration(config *iam_pb.S3Ap
 	iam.emailAccount = emailAccount
 	iam.accessKeyIdent = accessKeyIdent
 	iam.nameToIdentity = nameToIdentity
+	iam.policies = policies
 	// Update authentication state based on whether identities exist
 	// Once enabled, keep it enabled (one-way toggle)
 	authJustEnabled := iam.updateAuthenticationState(len(identities))
@@ -792,6 +810,56 @@ func (iam *IdentityAccessManagement) mergeS3ApiConfiguration(config *iam_pb.S3Ap
 	return nil
 }
 
+func (iam *IdentityAccessManagement) RemoveIdentity(name string) {
+	glog.V(1).Infof("IAM: remove identity %s", name)
+	iam.m.Lock()
+	defer iam.m.Unlock()
+
+	identity, ok := iam.nameToIdentity[name]
+	if !ok {
+		return
+	}
+
+	if identity.IsStatic {
+		glog.V(1).Infof("IAM: skipping removal of static identity %s (immutable)", name)
+		return
+	}
+
+	// Remove from identities slice
+	for i, ident := range iam.identities {
+		if ident.Name == name {
+			iam.identities = append(iam.identities[:i], iam.identities[i+1:]...)
+			break
+		}
+	}
+
+	// Remove from maps
+	delete(iam.nameToIdentity, name)
+	for _, cred := range identity.Credentials {
+		if iam.accessKeyIdent[cred.AccessKey] == identity {
+			delete(iam.accessKeyIdent, cred.AccessKey)
+		}
+	}
+
+	if identity == iam.identityAnonymous {
+		iam.identityAnonymous = nil
+	}
+}
+
+func (iam *IdentityAccessManagement) UpsertIdentity(ident *iam_pb.Identity) error {
+	if ident == nil {
+		return fmt.Errorf("upsert identity failed: nil identity")
+
+	}
+	if ident.Name == "" {
+		return fmt.Errorf("upsert identity failed: empty identity name")
+	}
+	glog.V(1).Infof("IAM: upsert identity %s", ident.Name)
+	return iam.MergeS3ApiConfiguration(&iam_pb.S3ApiConfiguration{
+		Identities: []*iam_pb.Identity{ident},
+	})
+}
+
 // isEnabled reports whether S3 auth should be enforced for this server.
 //
 // Auth is considered enabled if either:
@@ -1316,6 +1384,7 @@ func (iam *IdentityAccessManagement) GetCredentialManager() *credential.Credenti
 
 // LoadS3ApiConfigurationFromCredentialManager loads configuration using the credential manager
 func (iam *IdentityAccessManagement) LoadS3ApiConfigurationFromCredentialManager() error {
+	glog.V(0).Infof("IAM: reloading configuration from credential manager")
 	glog.V(1).Infof("Loading S3 API configuration from credential manager")
 
 	s3ApiConfiguration, err := iam.credentialManager.LoadConfiguration(context.Background())
@@ -1503,3 +1572,43 @@ func (iam *IdentityAccessManagement) authorizeWithIAM(r *http.Request, identity
 	// Use IAM integration for authorization
 	return iam.iamIntegration.AuthorizeAction(ctx, iamIdentity, action, bucket, object, r)
 }
+
+// PutPolicy adds or updates a policy
+func (iam *IdentityAccessManagement) PutPolicy(name string, content string) error {
+	iam.m.Lock()
+	defer iam.m.Unlock()
+	if iam.policies == nil {
+		iam.policies = make(map[string]*iam_pb.Policy)
+	}
+	iam.policies[name] = &iam_pb.Policy{Name: name, Content: content}
+	return nil
+}
+
+// GetPolicy retrieves a policy by name
+func (iam *IdentityAccessManagement) GetPolicy(name string) (*iam_pb.Policy, error) {
+	iam.m.RLock()
+	defer iam.m.RUnlock()
+	if policy, ok := iam.policies[name]; ok {
+		return policy, nil
+	}
+	return nil, fmt.Errorf("policy not found: %s", name)
+}
+
+// DeletePolicy removes a policy
+func (iam *IdentityAccessManagement) DeletePolicy(name string) error {
+	iam.m.Lock()
+	defer iam.m.Unlock()
+	delete(iam.policies, name)
+	return nil
+}
+
+// ListPolicies lists all policies
+func (iam *IdentityAccessManagement) ListPolicies() []*iam_pb.Policy {
+	iam.m.RLock()
+	defer iam.m.RUnlock()
+	var policies []*iam_pb.Policy
+	for _, p := range iam.policies {
+		policies = append(policies, p)
+	}
+	return policies
+}
diff --git a/weed/s3api/auth_credentials_test.go b/weed/s3api/auth_credentials_test.go
index b01d8e3ce..1db245b88 100644
--- a/weed/s3api/auth_credentials_test.go
+++ b/weed/s3api/auth_credentials_test.go
@@ -13,6 +13,9 @@ import (
 
 	"github.com/seaweedfs/seaweedfs/weed/pb/iam_pb"
 	jsonpb "google.golang.org/protobuf/encoding/protojson"
+
+	_ "github.com/seaweedfs/seaweedfs/weed/credential/filer_etc"
+	_ "github.com/seaweedfs/seaweedfs/weed/credential/memory"
 )
 
 func TestIdentityListFileFormat(t *testing.T) {
@@ -742,3 +745,48 @@ func TestSignatureVerificationDoesNotCheckPermissions(t *testing.T) {
 	t.Log("Signature verification no longer checks for Write permission")
 	t.Log("This allows list-only and read-only users to authenticate via AWS Signature V4")
 }
+
+func TestStaticIdentityProtection(t *testing.T) {
+	iam := NewIdentityAccessManagement(&S3ApiServerOption{})
+
+	// Add a static identity
+	staticIdent := &Identity{
+		Name:     "static-user",
+		IsStatic: true,
+	}
+	iam.m.Lock()
+	if iam.nameToIdentity == nil {
+		iam.nameToIdentity = make(map[string]*Identity)
+	}
+	iam.identities = append(iam.identities, staticIdent)
+	iam.nameToIdentity[staticIdent.Name] = staticIdent
+	iam.m.Unlock()
+
+	// Add a dynamic identity
+	dynamicIdent := &Identity{
+		Name:     "dynamic-user",
+		IsStatic: false,
+	}
+	iam.m.Lock()
+	iam.identities = append(iam.identities, dynamicIdent)
+	iam.nameToIdentity[dynamicIdent.Name] = dynamicIdent
+	iam.m.Unlock()
+
+	// Try to remove static identity
+	iam.RemoveIdentity("static-user")
+
+	// Verify static identity still exists
+	iam.m.RLock()
+	_, ok := iam.nameToIdentity["static-user"]
+	iam.m.RUnlock()
+	assert.True(t, ok, "Static identity should not be removed")
+
+	// Try to remove dynamic identity
+	iam.RemoveIdentity("dynamic-user")
+
+	// Verify dynamic identity is removed
+	iam.m.RLock()
+	_, ok = iam.nameToIdentity["dynamic-user"]
+	iam.m.RUnlock()
+	assert.False(t, ok, "Dynamic identity should have been removed")
+}
diff --git a/weed/s3api/s3api_bucket_policy_engine.go b/weed/s3api/s3api_bucket_policy_engine.go
index 3be063b35..1a014a919 100644
--- a/weed/s3api/s3api_bucket_policy_engine.go
+++ b/weed/s3api/s3api_bucket_policy_engine.go
@@ -83,6 +83,16 @@ func (bpe *BucketPolicyEngine) HasPolicyForBucket(bucket string) bool {
 	return bpe.engine.HasPolicyForBucket(bucket)
 }
 
+// GetBucketPolicy gets the policy for a bucket
+func (bpe *BucketPolicyEngine) GetBucketPolicy(bucket string) (*policy_engine.PolicyDocument, error) {
+	return bpe.engine.GetBucketPolicy(bucket)
+}
+
+// ListBucketPolicies returns all buckets that have policies
+func (bpe *BucketPolicyEngine) ListBucketPolicies() []string {
+	return bpe.engine.GetAllBucketsWithPolicies()
+}
+
 // EvaluatePolicy evaluates whether an action is allowed by bucket policy
 //
 // Parameters:
diff --git a/weed/s3api/s3api_embedded_iam.go b/weed/s3api/s3api_embedded_iam.go
index 8d775e0c7..7181410f1 100644
--- a/weed/s3api/s3api_embedded_iam.go
+++ b/weed/s3api/s3api_embedded_iam.go
@@ -38,13 +38,15 @@ type EmbeddedIamApi struct {
 	getS3ApiConfigurationFunc func(*iam_pb.S3ApiConfiguration) error
 	putS3ApiConfigurationFunc func(*iam_pb.S3ApiConfiguration) error
 	reloadConfigurationFunc   func() error
+	readOnly                  bool
 }
 
 // NewEmbeddedIamApi creates a new embedded IAM API handler.
-func NewEmbeddedIamApi(credentialManager *credential.CredentialManager, iam *IdentityAccessManagement) *EmbeddedIamApi {
+func NewEmbeddedIamApi(credentialManager *credential.CredentialManager, iam *IdentityAccessManagement, readOnly bool) *EmbeddedIamApi {
 	return &EmbeddedIamApi{
 		credentialManager: credentialManager,
 		iam:               iam,
+		readOnly:          readOnly,
 	}
 }
 
@@ -160,6 +162,8 @@ func (e *EmbeddedIamApi) writeIamErrorResponse(w http.ResponseWriter, r *http.Re
 		s3err.WriteXMLResponse(w, r, http.StatusConflict, errorResp)
 	case iam.ErrCodeMalformedPolicyDocumentException, iam.ErrCodeInvalidInputException:
 		s3err.WriteXMLResponse(w, r, http.StatusBadRequest, errorResp)
+	case "AccessDenied", iam.ErrCodeLimitExceededException:
+		s3err.WriteXMLResponse(w, r, http.StatusForbidden, errorResp)
 	case iam.ErrCodeServiceFailureException:
 		s3err.WriteXMLResponse(w, r, http.StatusInternalServerError, internalErrorResponse)
 	default:
@@ -190,6 +194,7 @@ func (e *EmbeddedIamApi) PutS3ApiConfiguration(s3cfg *iam_pb.S3ApiConfiguration)
 
 // ReloadConfiguration reloads the IAM configuration from the credential manager.
 func (e *EmbeddedIamApi) ReloadConfiguration() error {
+	glog.V(4).Infof("IAM: reloading configuration via EmbeddedIamApi")
 	if e.reloadConfigurationFunc != nil {
 		return e.reloadConfigurationFunc()
 	}
@@ -1043,11 +1048,22 @@ func (e *EmbeddedIamApi) AuthIam(f http.HandlerFunc, _ Action) http.HandlerFunc
 }
 
 // ExecuteAction executes an IAM action with the given values.
-func (e *EmbeddedIamApi) ExecuteAction(values url.Values) (interface{}, *iamError) {
+// If skipPersist is true, the changed configuration is not saved to the persistent store.
+func (e *EmbeddedIamApi) ExecuteAction(values url.Values, skipPersist bool) (interface{}, *iamError) {
 	// Lock to prevent concurrent read-modify-write race conditions
 	e.policyLock.Lock()
 	defer e.policyLock.Unlock()
 
+	action := values.Get("Action")
+	if e.readOnly {
+		switch action {
+		case "ListUsers", "ListAccessKeys", "GetUser", "GetUserPolicy", "ListServiceAccounts", "GetServiceAccount":
+			// Allowed read-only actions
+		default:
+			return nil, &iamError{Code: s3err.GetAPIError(s3err.ErrAccessDenied).Code, Error: fmt.Errorf("IAM write operations are disabled on this server")}
+		}
+	}
+
 	s3cfg := &iam_pb.S3ApiConfiguration{}
 	if err := e.GetS3ApiConfiguration(s3cfg); err != nil && !errors.Is(err, filer_pb.ErrNotFound) {
 		return nil, &iamError{Code: s3err.GetAPIError(s3err.ErrInternalError).Code, Error: fmt.Errorf("failed to get s3 api configuration: %v", err)}
@@ -1165,9 +1181,11 @@ func (e *EmbeddedIamApi) ExecuteAction(values url.Values) (interface{}, *iamErro
 		return nil, &iamError{Code: s3err.GetAPIError(s3err.ErrNotImplemented).Code, Error: errors.New(s3err.GetAPIError(s3err.ErrNotImplemented).Description)}
 	}
 	if changed {
-		if err := e.PutS3ApiConfiguration(s3cfg); err != nil {
-			iamErr = &iamError{Code: iam.ErrCodeServiceFailureException, Error: err}
-			return nil, iamErr
+		if !skipPersist {
+			if err := e.PutS3ApiConfiguration(s3cfg); err != nil {
+				iamErr = &iamError{Code: iam.ErrCodeServiceFailureException, Error: err}
+				return nil, iamErr
+			}
 		}
 		// Reload in-memory identity maps so subsequent LookupByAccessKey calls
 		// can see newly created or deleted keys immediately
@@ -1196,7 +1214,7 @@ func (e *EmbeddedIamApi) DoActions(w http.ResponseWriter, r *http.Request) {
 		values.Set("CreatedBy", createdBy)
 	}
 
-	response, iamErr := e.ExecuteAction(values)
+	response, iamErr := e.ExecuteAction(values, false)
 	if iamErr != nil {
 		e.writeIamErrorResponse(w, r, iamErr)
 		return
diff --git a/weed/s3api/s3api_embedded_iam_test.go b/weed/s3api/s3api_embedded_iam_test.go
index c5dc5d949..8ac0472cc 100644
--- a/weed/s3api/s3api_embedded_iam_test.go
+++ b/weed/s3api/s3api_embedded_iam_test.go
@@ -87,7 +87,19 @@ func (e *EmbeddedIamApiForTest) DoActions(w http.ResponseWriter, r *http.Request
 	var iamErr *iamError
 	changed := true
 
-	switch r.Form.Get("Action") {
+	action := r.Form.Get("Action")
+
+	if e.readOnly {
+		switch action {
+		case "ListUsers", "ListAccessKeys", "GetUser", "GetUserPolicy", "ListServiceAccounts", "GetServiceAccount":
+			// Allowed read-only actions
+		default:
+			e.writeIamErrorResponse(w, r, &iamError{Code: s3err.GetAPIError(s3err.ErrAccessDenied).Code, Error: fmt.Errorf("IAM write operations are disabled on this server")})
+			return
+		}
+	}
+
+	switch action {
 	case "ListUsers":
 		response = e.ListUsers(s3cfg, values)
 		changed = false
@@ -1691,7 +1703,7 @@ func TestEmbeddedIamExecuteAction(t *testing.T) {
 	vals.Set("Action", "CreateUser")
 	vals.Set("UserName", "ExecuteActionUser")
 
-	resp, iamErr := api.ExecuteAction(vals)
+	resp, iamErr := api.ExecuteAction(vals, false)
 	assert.Nil(t, iamErr)
 
 	// Verify response type
@@ -1703,3 +1715,33 @@ func TestEmbeddedIamExecuteAction(t *testing.T) {
 	assert.Len(t, api.mockConfig.Identities, 1)
 	assert.Equal(t, "ExecuteActionUser", api.mockConfig.Identities[0].Name)
 }
+
+// TestEmbeddedIamReadOnly tests that write operations are blocked when readOnly is true
+func TestEmbeddedIamReadOnly(t *testing.T) {
+	api := NewEmbeddedIamApiForTest()
+	api.readOnly = true
+
+	// Try CreateUser (Write)
+	userName := aws.String("ReadOnlyUser")
+	params := &iam.CreateUserInput{UserName: userName}
+	req, _ := iam.New(session.New()).CreateUserRequest(params)
+	_ = req.Build()
+
+	response, err := executeEmbeddedIamRequest(api, req.HTTPRequest, nil)
+	assert.NoError(t, err)
+	assert.Equal(t, http.StatusForbidden, response.Code)
+
+	code, msg := extractEmbeddedIamErrorCodeAndMessage(response)
+	assert.Equal(t, "AccessDenied", code)
+	assert.Contains(t, msg, "IAM write operations are disabled")
+
+	// Try ListUsers (Read) - Should succeed
+	paramsList := &iam.ListUsersInput{}
+	reqList, _ := iam.New(session.New()).ListUsersRequest(paramsList)
+	_ = reqList.Build()
+
+	outList := iamListUsersResponse{}
+	responseList, err := executeEmbeddedIamRequest(api, reqList.HTTPRequest, &outList)
+	assert.NoError(t, err)
+	assert.Equal(t, http.StatusOK, responseList.Code)
+}
diff --git a/weed/s3api/s3api_server.go b/weed/s3api/s3api_server.go
index 7670773e6..c72669795 100644
--- a/weed/s3api/s3api_server.go
+++ b/weed/s3api/s3api_server.go
@@ -52,11 +52,14 @@ type S3ApiServerOption struct {
 	ConcurrentUploadLimit     int64
 	ConcurrentFileUploadLimit int64
 	EnableIam                 bool // Enable embedded IAM API on the same port
+	IamReadOnly               bool // Disable IAM write operations on this server
 	Cipher                    bool // encrypt data on volume servers
+	BindIp                    string
+	GrpcPort                  int
 }
 
 type S3ApiServer struct {
-	s3_pb.UnimplementedSeaweedS3Server
+	s3_pb.UnimplementedSeaweedS3IamCacheServer
 	option                *S3ApiServerOption
 	iam                   *IdentityAccessManagement
 	iamIntegration        *S3IAMIntegration // Advanced IAM integration for JWT authentication
@@ -114,13 +117,17 @@ func NewS3ApiServerWithStore(router *mux.Router, option *S3ApiServerOption, expl
 	// Uses the battle-tested vidMap with filer-based lookups
 	// Supports multiple filer addresses with automatic failover for high availability
 	var filerClient *wdclient.FilerClient
-	if len(option.Masters) > 0 && option.FilerGroup != "" {
+	if len(option.Masters) > 0 {
 		// Enable filer discovery via master
 		masterMap := make(map[string]pb.ServerAddress)
 		for i, addr := range option.Masters {
 			masterMap[fmt.Sprintf("master%d", i)] = addr
 		}
-		masterClient := wdclient.NewMasterClient(option.GrpcDialOption, option.FilerGroup, cluster.S3Type, "", "", "", *pb.NewServiceDiscoveryFromMap(masterMap))
+		clientHost := option.BindIp
+		if clientHost == "0.0.0.0" || clientHost == "" {
+			clientHost = util.DetectedHostAddress()
+		}
+		masterClient := wdclient.NewMasterClient(option.GrpcDialOption, option.FilerGroup, cluster.S3Type, pb.ServerAddress(util.JoinHostPort(clientHost, option.GrpcPort)), "", "", *pb.NewServiceDiscoveryFromMap(masterMap))
 		// Start the master client connection loop - required for GetMaster() to work
 		go masterClient.KeepConnectedToMaster(context.Background())
 
@@ -203,8 +210,12 @@ func NewS3ApiServerWithStore(router *mux.Router, option *S3ApiServerOption, expl
 
 	// Initialize embedded IAM API if enabled
 	if option.EnableIam {
-		s3ApiServer.embeddedIam = NewEmbeddedIamApi(s3ApiServer.credentialManager, iam)
-		glog.V(1).Infof("Embedded IAM API initialized (use -iam=false to disable)")
+		s3ApiServer.embeddedIam = NewEmbeddedIamApi(s3ApiServer.credentialManager, iam, option.IamReadOnly)
+		if option.IamReadOnly {
+			glog.V(1).Infof("Embedded IAM API initialized in read-only mode (use -s3.iam.readOnly=false to enable write operations)")
+		} else {
+			glog.V(1).Infof("Embedded IAM API initialized in writable mode (WARNING: updates will not be propagated to other S3 servers)")
+		}
 	}
 
 	if option.Config != "" {
diff --git a/weed/s3api/s3api_server_grpc.go b/weed/s3api/s3api_server_grpc.go
index 2f6976b56..c8b55f5f1 100644
--- a/weed/s3api/s3api_server_grpc.go
+++ b/weed/s3api/s3api_server_grpc.go
@@ -4,341 +4,95 @@ import (
 	"context"
 
 	"fmt"
-	"net/url"
 
+	"github.com/seaweedfs/seaweedfs/weed/glog"
 	"github.com/seaweedfs/seaweedfs/weed/pb/iam_pb"
 )
 
-func (s3a *S3ApiServer) executeAction(values url.Values) (interface{}, error) {
-	if s3a.embeddedIam == nil {
-		return nil, fmt.Errorf("embedded iam is disabled")
-	}
-	response, iamErr := s3a.embeddedIam.ExecuteAction(values)
-	if iamErr != nil {
-		return nil, fmt.Errorf("IAM error: %s - %v", iamErr.Code, iamErr.Error)
-	}
-	return response, nil
-}
-
-func (s3a *S3ApiServer) ListUsers(ctx context.Context, req *iam_pb.ListUsersRequest) (*iam_pb.ListUsersResponse, error) {
-	values := url.Values{}
-	values.Set("Action", "ListUsers")
-	resp, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	iamResp, ok := resp.(iamListUsersResponse)
-	if !ok {
-		return nil, fmt.Errorf("unexpected IAM ListUsers response type %T", resp)
-	}
-	var usernames []string
-	for _, user := range iamResp.ListUsersResult.Users {
-		if user != nil && user.UserName != nil {
-			usernames = append(usernames, *user.UserName)
-		}
-	}
-	return &iam_pb.ListUsersResponse{Usernames: usernames}, nil
-}
-
-func (s3a *S3ApiServer) CreateUser(ctx context.Context, req *iam_pb.CreateUserRequest) (*iam_pb.CreateUserResponse, error) {
-	if req.Identity == nil || req.Identity.Name == "" {
-		return nil, fmt.Errorf("username name is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "CreateUser")
-	values.Set("UserName", req.Identity.Name)
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	return &iam_pb.CreateUserResponse{}, nil
-}
-
-func (s3a *S3ApiServer) GetUser(ctx context.Context, req *iam_pb.GetUserRequest) (*iam_pb.GetUserResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "GetUser")
-	values.Set("UserName", req.Username)
-	resp, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	iamResp, ok := resp.(iamGetUserResponse)
-	if !ok {
-		return nil, fmt.Errorf("unexpected IAM GetUser response type %T", resp)
-	}
-
-	var username string
-	if iamResp.GetUserResult.User.UserName != nil {
-		username = *iamResp.GetUserResult.User.UserName
-	}
-
-	return &iam_pb.GetUserResponse{
-		Identity: &iam_pb.Identity{
-			Name: username,
-		},
-	}, nil
-}
+// SeaweedS3IamCacheServer Implementation
+// This interface is dedicated to UNIDIRECTIONAL updates from Filer to S3 Server.
+// S3 Server acts purely as a cache.
 
-func (s3a *S3ApiServer) UpdateUser(ctx context.Context, req *iam_pb.UpdateUserRequest) (*iam_pb.UpdateUserResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "UpdateUser")
-	values.Set("UserName", req.Username)
-	// UpdateUser in DoActions expects "NewUserName" if renaming, but CreateUser just takes UserName.
-	// Looking at s3api_embedded_iam.go, UpdateUser uses "NewUserName" to change name.
-	if req.Identity != nil && req.Identity.Name != "" {
-		values.Set("NewUserName", req.Identity.Name)
+func (s3a *S3ApiServer) PutIdentity(ctx context.Context, req *iam_pb.PutIdentityRequest) (*iam_pb.PutIdentityResponse, error) {
+	if req.Identity == nil {
+		return nil, fmt.Errorf("identity is required")
 	}
-	_, err := s3a.executeAction(values)
-	if err != nil {
+	// Direct in-memory cache update
+	glog.V(1).Infof("IAM: received identity update for %s", req.Identity.Name)
+	if err := s3a.iam.UpsertIdentity(req.Identity); err != nil {
+		glog.Errorf("failed to update identity cache for %s: %v", req.Identity.Name, err)
 		return nil, err
 	}
-	return &iam_pb.UpdateUserResponse{}, nil
+	return &iam_pb.PutIdentityResponse{}, nil
 }
 
-func (s3a *S3ApiServer) DeleteUser(ctx context.Context, req *iam_pb.DeleteUserRequest) (*iam_pb.DeleteUserResponse, error) {
+func (s3a *S3ApiServer) RemoveIdentity(ctx context.Context, req *iam_pb.RemoveIdentityRequest) (*iam_pb.RemoveIdentityResponse, error) {
 	if req.Username == "" {
 		return nil, fmt.Errorf("username is required")
 	}
-	values := url.Values{}
-	values.Set("Action", "DeleteUser")
-	values.Set("UserName", req.Username)
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	return &iam_pb.DeleteUserResponse{}, nil
+	// Direct in-memory cache update
+	glog.V(1).Infof("IAM: received identity removal for %s", req.Username)
+	s3a.iam.RemoveIdentity(req.Username)
+	return &iam_pb.RemoveIdentityResponse{}, nil
 }
 
-func (s3a *S3ApiServer) ListAccessKeys(ctx context.Context, req *iam_pb.ListAccessKeysRequest) (*iam_pb.ListAccessKeysResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "ListAccessKeys")
-	values.Set("UserName", req.Username)
-	resp, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	iamResp, ok := resp.(iamListAccessKeysResponse)
-	if !ok {
-		return nil, fmt.Errorf("unexpected IAM ListAccessKeys response type %T", resp)
-	}
-	var accessKeys []*iam_pb.Credential
-	for _, meta := range iamResp.ListAccessKeysResult.AccessKeyMetadata {
-		if meta != nil && meta.AccessKeyId != nil && meta.Status != nil {
-			accessKeys = append(accessKeys, &iam_pb.Credential{
-				AccessKey: *meta.AccessKeyId,
-				Status:    *meta.Status,
-			})
-		}
-	}
-	return &iam_pb.ListAccessKeysResponse{AccessKeys: accessKeys}, nil
-}
-
-func (s3a *S3ApiServer) CreateAccessKey(ctx context.Context, req *iam_pb.CreateAccessKeyRequest) (*iam_pb.CreateAccessKeyResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "CreateAccessKey")
-	values.Set("UserName", req.Username)
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	return &iam_pb.CreateAccessKeyResponse{}, nil
-}
-
-func (s3a *S3ApiServer) DeleteAccessKey(ctx context.Context, req *iam_pb.DeleteAccessKeyRequest) (*iam_pb.DeleteAccessKeyResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	if req.AccessKey == "" {
-		return nil, fmt.Errorf("access key is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "DeleteAccessKey")
-	values.Set("UserName", req.Username)
-	values.Set("AccessKeyId", req.AccessKey)
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	return &iam_pb.DeleteAccessKeyResponse{}, nil
-}
-
-func (s3a *S3ApiServer) PutUserPolicy(ctx context.Context, req *iam_pb.PutUserPolicyRequest) (*iam_pb.PutUserPolicyResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	if req.PolicyName == "" {
+func (s3a *S3ApiServer) PutPolicy(ctx context.Context, req *iam_pb.PutPolicyRequest) (*iam_pb.PutPolicyResponse, error) {
+	if req.Name == "" {
 		return nil, fmt.Errorf("policy name is required")
 	}
-	values := url.Values{}
-	values.Set("Action", "PutUserPolicy")
-	values.Set("UserName", req.Username)
-	values.Set("PolicyName", req.PolicyName)
-	values.Set("PolicyDocument", req.PolicyDocument)
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	return &iam_pb.PutUserPolicyResponse{}, nil
-}
 
-func (s3a *S3ApiServer) GetUserPolicy(ctx context.Context, req *iam_pb.GetUserPolicyRequest) (*iam_pb.GetUserPolicyResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	if req.PolicyName == "" {
-		return nil, fmt.Errorf("policy name is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "GetUserPolicy")
-	values.Set("UserName", req.Username)
-	values.Set("PolicyName", req.PolicyName)
-	resp, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	iamResp, ok := resp.(iamGetUserPolicyResponse)
-	if !ok {
-		return nil, fmt.Errorf("unexpected IAM GetUserPolicy response type %T", resp)
+	// Update IAM policy cache
+	glog.V(1).Infof("IAM: received policy update for %s", req.Name)
+	if s3a.iam != nil {
+		if err := s3a.iam.PutPolicy(req.Name, req.Content); err != nil {
+			glog.Errorf("failed to update policy cache for %s: %v", req.Name, err)
+			return nil, err
+		}
 	}
-	return &iam_pb.GetUserPolicyResponse{
-		Username:       iamResp.GetUserPolicyResult.UserName,
-		PolicyName:     iamResp.GetUserPolicyResult.PolicyName,
-		PolicyDocument: iamResp.GetUserPolicyResult.PolicyDocument,
-	}, nil
+	return &iam_pb.PutPolicyResponse{}, nil
 }
 
-func (s3a *S3ApiServer) DeleteUserPolicy(ctx context.Context, req *iam_pb.DeleteUserPolicyRequest) (*iam_pb.DeleteUserPolicyResponse, error) {
-	if req.Username == "" {
-		return nil, fmt.Errorf("username is required")
-	}
-	if req.PolicyName == "" {
+func (s3a *S3ApiServer) DeletePolicy(ctx context.Context, req *iam_pb.DeletePolicyRequest) (*iam_pb.DeletePolicyResponse, error) {
+	if req.Name == "" {
 		return nil, fmt.Errorf("policy name is required")
 	}
-	values := url.Values{}
-	values.Set("Action", "DeleteUserPolicy")
-	values.Set("UserName", req.Username)
-	values.Set("PolicyName", req.PolicyName)
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	return &iam_pb.DeleteUserPolicyResponse{}, nil
-}
 
-func (s3a *S3ApiServer) ListServiceAccounts(ctx context.Context, req *iam_pb.ListServiceAccountsRequest) (*iam_pb.ListServiceAccountsResponse, error) {
-	values := url.Values{}
-	values.Set("Action", "ListServiceAccounts")
-	resp, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	iamResp, ok := resp.(iamListServiceAccountsResponse)
-	if !ok {
-		return nil, fmt.Errorf("unexpected IAM ListServiceAccounts response type %T", resp)
-	}
-	var serviceAccounts []*iam_pb.ServiceAccount
-	for _, sa := range iamResp.ListServiceAccountsResult.ServiceAccounts {
-		if sa != nil {
-			serviceAccounts = append(serviceAccounts, &iam_pb.ServiceAccount{
-				Id:          sa.ServiceAccountId,
-				ParentUser:  sa.ParentUser,
-				Description: sa.Description,
-				Credential: &iam_pb.Credential{
-					AccessKey: sa.AccessKeyId,
-					Status:    sa.Status,
-				},
-			})
+	// Delete from IAM policy cache
+	glog.V(1).Infof("IAM: received policy removal for %s", req.Name)
+	if s3a.iam != nil {
+		if err := s3a.iam.DeletePolicy(req.Name); err != nil {
+			glog.Errorf("failed to delete policy cache for %s: %v", req.Name, err)
+			return nil, err
 		}
 	}
-	return &iam_pb.ListServiceAccountsResponse{ServiceAccounts: serviceAccounts}, nil
-}
-
-func (s3a *S3ApiServer) CreateServiceAccount(ctx context.Context, req *iam_pb.CreateServiceAccountRequest) (*iam_pb.CreateServiceAccountResponse, error) {
-	if req.ServiceAccount == nil || req.ServiceAccount.CreatedBy == "" {
-		return nil, fmt.Errorf("service account owner is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "CreateServiceAccount")
-	values.Set("CreatedBy", req.ServiceAccount.CreatedBy)
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
-	}
-	return &iam_pb.CreateServiceAccountResponse{}, nil
+	return &iam_pb.DeletePolicyResponse{}, nil
 }
 
-func (s3a *S3ApiServer) UpdateServiceAccount(ctx context.Context, req *iam_pb.UpdateServiceAccountRequest) (*iam_pb.UpdateServiceAccountResponse, error) {
-	if req.Id == "" {
-		return nil, fmt.Errorf("service account id is required")
-	}
-	values := url.Values{}
-	values.Set("Action", "UpdateServiceAccount")
-	values.Set("ServiceAccountId", req.Id)
-	if req.ServiceAccount != nil && req.ServiceAccount.Disabled {
-		values.Set("Status", "Inactive")
-	}
-	_, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
+func (s3a *S3ApiServer) GetPolicy(ctx context.Context, req *iam_pb.GetPolicyRequest) (*iam_pb.GetPolicyResponse, error) {
+	if req.Name == "" {
+		return nil, fmt.Errorf("policy name is required")
 	}
-	return &iam_pb.UpdateServiceAccountResponse{}, nil
-}
-
-func (s3a *S3ApiServer) DeleteServiceAccount(ctx context.Context, req *iam_pb.DeleteServiceAccountRequest) (*iam_pb.DeleteServiceAccountResponse, error) {
-	if req.Id == "" {
-		return nil, fmt.Errorf("service account id is required")
+	if s3a.iam == nil {
+		return &iam_pb.GetPolicyResponse{}, nil
 	}
-	values := url.Values{}
-	values.Set("Action", "DeleteServiceAccount")
-	values.Set("ServiceAccountId", req.Id)
-	_, err := s3a.executeAction(values)
+	policy, err := s3a.iam.GetPolicy(req.Name)
 	if err != nil {
-		return nil, err
+		return &iam_pb.GetPolicyResponse{}, nil // Not found is fine for cache
 	}
-	return &iam_pb.DeleteServiceAccountResponse{}, nil
+	return &iam_pb.GetPolicyResponse{
+		Name:    policy.Name,
+		Content: policy.Content,
+	}, nil
 }
 
-func (s3a *S3ApiServer) GetServiceAccount(ctx context.Context, req *iam_pb.GetServiceAccountRequest) (*iam_pb.GetServiceAccountResponse, error) {
-	if req.Id == "" {
-		return nil, fmt.Errorf("service account id is required")
+func (s3a *S3ApiServer) ListPolicies(ctx context.Context, req *iam_pb.ListPoliciesRequest) (*iam_pb.ListPoliciesResponse, error) {
+	resp := &iam_pb.ListPoliciesResponse{}
+	if s3a.iam == nil {
+		return resp, nil
 	}
-	values := url.Values{}
-	values.Set("Action", "GetServiceAccount")
-	values.Set("ServiceAccountId", req.Id)
-	resp, err := s3a.executeAction(values)
-	if err != nil {
-		return nil, err
+	policies := s3a.iam.ListPolicies()
+	for _, policy := range policies {
+		resp.Policies = append(resp.Policies, policy)
 	}
-	iamResp, ok := resp.(iamGetServiceAccountResponse)
-	if !ok {
-		return nil, fmt.Errorf("unexpected IAM GetServiceAccount response type %T", resp)
-	}
-
-	var serviceAccount *iam_pb.ServiceAccount
-	sa := iamResp.GetServiceAccountResult.ServiceAccount
-	serviceAccount = &iam_pb.ServiceAccount{
-		Id:          sa.ServiceAccountId,
-		ParentUser:  sa.ParentUser,
-		Description: sa.Description,
-		Credential: &iam_pb.Credential{
-			AccessKey: sa.AccessKeyId,
-			Status:    sa.Status,
-		},
-	}
-
-	return &iam_pb.GetServiceAccountResponse{
-		ServiceAccount: serviceAccount,
-	}, nil
+	return resp, nil
 }
diff --git a/weed/s3api/s3api_server_routing_test.go b/weed/s3api/s3api_server_routing_test.go
index 2746d59fe..52ecd20e5 100644
--- a/weed/s3api/s3api_server_routing_test.go
+++ b/weed/s3api/s3api_server_routing_test.go
@@ -31,7 +31,7 @@ func setupRoutingTestServer(t *testing.T) *S3ApiServer {
 		option:            opt,
 		iam:               iam,
 		credentialManager: iam.credentialManager,
-		embeddedIam:       NewEmbeddedIamApi(iam.credentialManager, iam),
+		embeddedIam:       NewEmbeddedIamApi(iam.credentialManager, iam, false),
 		stsHandlers:       &STSHandlers{},
 	}
 
diff --git a/weed/server/filer_server.go b/weed/server/filer_server.go
index f76d215aa..3ec247ffd 100644
--- a/weed/server/filer_server.go
+++ b/weed/server/filer_server.go
@@ -256,6 +256,10 @@ func NewFilerServer(defaultMux, readonlyMux *http.ServeMux, option *FilerOption)
 
 	fs.filer.Dlm.LockRing.SetTakeSnapshotCallback(fs.OnDlmChangeSnapshot)
 
+	if fs.CredentialManager != nil {
+		fs.CredentialManager.SetMasterClient(fs.filer.MasterClient, fs.grpcDialOption)
+	}
+
 	return fs, nil
 }
 
diff --git a/weed/server/filer_server_handlers_iam_grpc.go b/weed/server/filer_server_handlers_iam_grpc.go
index 777c9f2d4..c77cf8914 100644
--- a/weed/server/filer_server_handlers_iam_grpc.go
+++ b/weed/server/filer_server_handlers_iam_grpc.go
@@ -73,7 +73,7 @@ func (s *IamGrpcServer) CreateUser(ctx context.Context, req *iam_pb.CreateUserRe
 	if req == nil || req.Identity == nil {
 		return nil, status.Errorf(codes.InvalidArgument, "identity is required")
 	}
-	glog.V(4).Infof("CreateUser: %s", req.Identity.Name)
+	glog.V(4).Infof("IAM: Filer.CreateUser %s", req.Identity.Name)
 
 	if s.credentialManager == nil {
 		return nil, status.Errorf(codes.FailedPrecondition, "credential manager is not configured")
@@ -113,10 +113,10 @@ func (s *IamGrpcServer) GetUser(ctx context.Context, req *iam_pb.GetUserRequest)
 }
 
 func (s *IamGrpcServer) UpdateUser(ctx context.Context, req *iam_pb.UpdateUserRequest) (*iam_pb.UpdateUserResponse, error) {
-	glog.V(4).Infof("UpdateUser: %s", req.Username)
 	if req == nil || req.Identity == nil {
 		return nil, status.Errorf(codes.InvalidArgument, "identity is required")
 	}
+	glog.V(4).Infof("IAM: Filer.UpdateUser %s", req.Username)
 
 	if s.credentialManager == nil {
 		return nil, status.Errorf(codes.FailedPrecondition, "credential manager is not configured")
@@ -135,7 +135,7 @@ func (s *IamGrpcServer) UpdateUser(ctx context.Context, req *iam_pb.UpdateUserRe
 }
 
 func (s *IamGrpcServer) DeleteUser(ctx context.Context, req *iam_pb.DeleteUserRequest) (*iam_pb.DeleteUserResponse, error) {
-	glog.V(4).Infof("DeleteUser: %s", req.Username)
+	glog.V(4).Infof("IAM: Filer.DeleteUser %s", req.Username)
 
 	if s.credentialManager == nil {
 		return nil, status.Errorf(codes.FailedPrecondition, "credential manager is not configured")
@@ -243,7 +243,7 @@ func (s *IamGrpcServer) GetUserByAccessKey(ctx context.Context, req *iam_pb.GetU
 // Policy Management
 
 func (s *IamGrpcServer) PutPolicy(ctx context.Context, req *iam_pb.PutPolicyRequest) (*iam_pb.PutPolicyResponse, error) {
-	glog.V(4).Infof("PutPolicy: %s", req.Name)
+	glog.V(4).Infof("IAM: Filer.PutPolicy %s", req.Name)
 
 	if s.credentialManager == nil {
 		return nil, status.Errorf(codes.FailedPrecondition, "credential manager is not configured")
diff --git a/weed/server/master_grpc_server.go b/weed/server/master_grpc_server.go
index 255a0d7a7..7c6bd1e3c 100644
--- a/weed/server/master_grpc_server.go
+++ b/weed/server/master_grpc_server.go
@@ -276,6 +276,7 @@ func (ms *MasterServer) KeepConnected(stream master_pb.Seaweed_KeepConnectedServ
 
 	clientName, messageChan := ms.addClient(req.FilerGroup, req.ClientType, peerAddress)
 	for _, update := range ms.Cluster.AddClusterNode(req.FilerGroup, req.ClientType, cluster.DataCenter(req.DataCenter), cluster.Rack(req.Rack), peerAddress, req.Version) {
+		glog.V(1).Infof("Cluster: %s node %s added to group '%s'", req.ClientType, peerAddress, req.FilerGroup)
 		ms.broadcastToClients(update)
 	}