diff --git a/dnsapi/dns_geos.sh b/dnsapi/dns_geos.sh
index 423ff883..3cd8997e 100644
--- a/dnsapi/dns_geos.sh
+++ b/dnsapi/dns_geos.sh
@@ -1,4 +1,4 @@
-#!/usr/bin/bash
+#!/usr/bin/env sh
 ########################################################################
 # GeoScaling hook script for acme.sh
 #
@@ -70,10 +70,11 @@ dns_geos_rm() {
 _count() {
   echo "$1" | awk -F"$2" '{print NF-1}'
 }
-
-#$1:fullname,eg:_acme-challenge.us.domain.com
-#ret:return root domain,us.domain.com domain.com
+#Usage: local -a domains=(); _get_domain "_acme-challenge.us.domain.com" domains
+#$1:fullname
+#$2:return root domain array,us.domain.com domain.com
 _get_domain() {
+  local -n arr=$2 #use nameref for indirection
   i=2
   c=$(_count "$1" ".")
   while [ $i -le "$c" ]; do
@@ -81,7 +82,7 @@ _get_domain() {
     if [ -z "$h" ]; then
       return 1
     fi
-    echo "$h"
+    arr+=("$h")
     i=$(_math "$i" + 1)
   done
   return 0
@@ -121,13 +122,15 @@ _get_zone() {
   response=$(_get "https://www.geoscaling.com/dns2/index.php?module=domains")
   table=$(echo "$response" | tr -d "\n" | grep -oP "(?<=<table border='0' align='center' cellpadding='10' cellspacing='10' class=\"threecolumns\">).*?(?=</table>)")
   items=$(echo "$table" | grep -oP "(?<=<a).*?(?=</a>)")
-  domains=$(_get_domain "$1")
+  #_debug "items=$items"
+  domains=()
+  _get_domain "$1" domains || return 1
   for d in "${domains[@]}"; do
     id=$(echo "$items" | grep -oP "id=[0-9]*.*$d" | cut -d "'" -f 1)
     if [ -n "$id" ]; then
       _sub_domain=${1//.$d/}
       _zone_id=${id##*=}
-      #echo "$_zone_id"
+      _debug "zone_id=$_zone_id"
       return 0
     fi
   done