Update _get_root logic

dnsapi/dns_alviy.sh

@@ -103,11 +103,10 @@ dns_alviy_rm() {
 _get_root() {
   domain=$1
   i=2
-  p=1
-  while true; do
   h=$(printf "%s" "$domain" | rev | cut -d . -f 1-2 | rev)
   if [ -z "$h" ]; then
     #not valid
+	_debug "can't get host from $domain"
     return 1
   fi
 
@@ -118,13 +117,10 @@ _get_root() {
   if _contains "$response" '"code":"NOT_FOUND"'; then
     _debug "$h not found"
   else
-      _sub_domain=$(printf "%s" "$domain" | cut -d . -f 1-$p)
+    _sub_domain=$(printf "%s" "$domain" | rev | cut -d . -f 3- | rev)
     _domain="$h"
     return 0
   fi
-    p="$i"
-    i=$(_math "$i" + 1)
-  done
   return 1
 }