diff --git a/README.md b/README.md
index d6b2c555..9e3ec1a5 100644
--- a/README.md
+++ b/README.md
@@ -315,6 +315,13 @@ You don't have to do anything manually!
 1. Azure DNS
 1. selectel.com(selectel.ru) DNS API
 1. zonomi.com DNS API
+
+
+
+
+
+
+
 And: 
 
 1. lexicon DNS API: https://github.com/Neilpang/acme.sh/wiki/How-to-use-lexicon-dns-api
diff --git a/acme.sh b/acme.sh
index a4224fc9..b9e57a7b 100755
--- a/acme.sh
+++ b/acme.sh
@@ -4545,7 +4545,7 @@ _installcert() {
       cat "$CERT_KEY_PATH" >"$_real_key"
     else
       cat "$CERT_KEY_PATH" >"$_real_key"
-      chmod 700 "$_real_key"
+      chmod 600 "$_real_key"
     fi
   fi
 
diff --git a/dnsapi/README.md b/dnsapi/README.md
index 5ded260c..b5b73f47 100644
--- a/dnsapi/README.md
+++ b/dnsapi/README.md
@@ -409,10 +409,13 @@ acme.sh --issue --dns dns_dgon -d example.com -d www.example.com
 
 ## 21. Use ClouDNS.net API
 
-You need to set the HTTP API user ID and password credentials. See: https://www.cloudns.net/wiki/article/42/
+You need to set the HTTP API user ID and password credentials. See: https://www.cloudns.net/wiki/article/42/. For security reasons, it's recommended to use a sub user ID that only has access to the necessary zones, as a regular API user has access to your entire account.
 
 ```
-export CLOUDNS_AUTH_ID=XXXXX
+# Use this for a sub auth ID
+export CLOUDNS_SUB_AUTH_ID=XXXXX
+# Use this for a regular auth ID
+#export CLOUDNS_AUTH_ID=XXXXX
 export CLOUDNS_AUTH_PASSWORD="YYYYYYYYY"
 ```
 
@@ -585,7 +588,7 @@ For issues, please report to https://github.com/non7top/acme.sh/issues.
 
 ## 31. Use Hurricane Electric
 
-Hurricane Electric doesn't have an API so just set your login credentials like so:
+Hurricane Electric (https://dns.he.net/) doesn't have an API so just set your login credentials like so:
 
 ```
 export HE_Username="yourusername"
diff --git a/dnsapi/dns_aws.sh b/dnsapi/dns_aws.sh
index ed317460..ee8efb38 100755
--- a/dnsapi/dns_aws.sh
+++ b/dnsapi/dns_aws.sh
@@ -42,7 +42,26 @@ dns_aws_add() {
   _debug _sub_domain "$_sub_domain"
   _debug _domain "$_domain"
 
-  _aws_tmpl_xml="<ChangeResourceRecordSetsRequest xmlns=\"https://route53.amazonaws.com/doc/2013-04-01/\"><ChangeBatch><Changes><Change><Action>UPSERT</Action><ResourceRecordSet><Name>$fulldomain</Name><Type>TXT</Type><TTL>300</TTL><ResourceRecords><ResourceRecord><Value>\"$txtvalue\"</Value></ResourceRecord></ResourceRecords></ResourceRecordSet></Change></Changes></ChangeBatch></ChangeResourceRecordSetsRequest>"
+  _info "Geting existing records for $fulldomain"
+  if ! aws_rest GET "2013-04-01$_domain_id/rrset" "name=$fulldomain&type=TXT"; then
+    return 1
+  fi
+
+  if _contains "$response" "<Name>$fulldomain.</Name>"; then
+    _resource_record="$(echo "$response" | _egrep_o "<ResourceRecords.*</ResourceRecords>" | sed "s/<ResourceRecords>//" | sed "s#</ResourceRecords>##")"
+    _debug "_resource_record" "$_resource_record"
+  else
+    _debug "single new add"
+  fi
+
+  if [ "$_resource_record" ] && _contains "$response" "$txtvalue"; then
+    _info "The txt record already exists, skip"
+    return 0
+  fi
+
+  _debug "Adding records"
+
+  _aws_tmpl_xml="<ChangeResourceRecordSetsRequest xmlns=\"https://route53.amazonaws.com/doc/2013-04-01/\"><ChangeBatch><Changes><Change><Action>UPSERT</Action><ResourceRecordSet><Name>$fulldomain</Name><Type>TXT</Type><TTL>300</TTL><ResourceRecords>$_resource_record<ResourceRecord><Value>\"$txtvalue\"</Value></ResourceRecord></ResourceRecords></ResourceRecordSet></Change></Changes></ChangeBatch></ChangeResourceRecordSetsRequest>"
 
   if aws_rest POST "2013-04-01$_domain_id/rrset/" "" "$_aws_tmpl_xml" && _contains "$response" "ChangeResourceRecordSetsResponse"; then
     _info "txt record updated success."
@@ -68,7 +87,20 @@ dns_aws_rm() {
   _debug _sub_domain "$_sub_domain"
   _debug _domain "$_domain"
 
-  _aws_tmpl_xml="<ChangeResourceRecordSetsRequest xmlns=\"https://route53.amazonaws.com/doc/2013-04-01/\"><ChangeBatch><Changes><Change><Action>DELETE</Action><ResourceRecordSet><ResourceRecords><ResourceRecord><Value>\"$txtvalue\"</Value></ResourceRecord></ResourceRecords><Name>$fulldomain.</Name><Type>TXT</Type><TTL>300</TTL></ResourceRecordSet></Change></Changes></ChangeBatch></ChangeResourceRecordSetsRequest>"
+  _info "Geting existing records for $fulldomain"
+  if ! aws_rest GET "2013-04-01$_domain_id/rrset" "name=$fulldomain&type=TXT"; then
+    return 1
+  fi
+
+  if _contains "$response" "<Name>$fulldomain.</Name>"; then
+    _resource_record="$(echo "$response" | _egrep_o "<ResourceRecords.*</ResourceRecords>" | sed "s/<ResourceRecords>//" | sed "s#</ResourceRecords>##")"
+    _debug "_resource_record" "$_resource_record"
+  else
+    _debug "no records exists, skip"
+    return 0
+  fi
+
+  _aws_tmpl_xml="<ChangeResourceRecordSetsRequest xmlns=\"https://route53.amazonaws.com/doc/2013-04-01/\"><ChangeBatch><Changes><Change><Action>DELETE</Action><ResourceRecordSet><ResourceRecords>$_resource_record</ResourceRecords><Name>$fulldomain.</Name><Type>TXT</Type><TTL>300</TTL></ResourceRecordSet></Change></Changes></ChangeBatch></ChangeResourceRecordSetsRequest>"
 
   if aws_rest POST "2013-04-01$_domain_id/rrset/" "" "$_aws_tmpl_xml" && _contains "$response" "ChangeResourceRecordSetsResponse"; then
     _info "txt record deleted success."
@@ -87,7 +119,6 @@ _get_root() {
   p=1
 
   if aws_rest GET "2013-04-01/hostedzone"; then
-    _debug "response" "$response"
     while true; do
       h=$(printf "%s" "$domain" | cut -d . -f $i-100)
       _debug2 "Checking domain: $h"
@@ -236,6 +267,7 @@ aws_rest() {
   fi
 
   _ret="$?"
+  _debug2 response "$response"
   if [ "$_ret" = "0" ]; then
     if _contains "$response" "<ErrorResponse"; then
       _err "Response error:$response"
diff --git a/dnsapi/dns_cloudns.sh b/dnsapi/dns_cloudns.sh
index b1861b24..4a1ae641 100755
--- a/dnsapi/dns_cloudns.sh
+++ b/dnsapi/dns_cloudns.sh
@@ -4,6 +4,7 @@
 # Repository: https://github.com/ClouDNS/acme.sh/
 
 #CLOUDNS_AUTH_ID=XXXXX
+#CLOUDNS_SUB_AUTH_ID=XXXXX
 #CLOUDNS_AUTH_PASSWORD="YYYYYYYYY"
 CLOUDNS_API="https://api.cloudns.net"
 
@@ -97,17 +98,19 @@ _dns_cloudns_init_check() {
   fi
 
   CLOUDNS_AUTH_ID="${CLOUDNS_AUTH_ID:-$(_readaccountconf_mutable CLOUDNS_AUTH_ID)}"
+  CLOUDNS_SUB_AUTH_ID="${CLOUDNS_SUB_AUTH_ID:-$(_readaccountconf_mutable CLOUDNS_SUB_AUTH_ID)}"
   CLOUDNS_AUTH_PASSWORD="${CLOUDNS_AUTH_PASSWORD:-$(_readaccountconf_mutable CLOUDNS_AUTH_PASSWORD)}"
-  if [ -z "$CLOUDNS_AUTH_ID" ] || [ -z "$CLOUDNS_AUTH_PASSWORD" ]; then
+  if [ -z "$CLOUDNS_AUTH_ID$CLOUDNS_SUB_AUTH_ID" ] || [ -z "$CLOUDNS_AUTH_PASSWORD" ]; then
     CLOUDNS_AUTH_ID=""
+    CLOUDNS_SUB_AUTH_ID=""
     CLOUDNS_AUTH_PASSWORD=""
     _err "You don't specify cloudns api id and password yet."
     _err "Please create you id and password and try again."
     return 1
   fi
 
-  if [ -z "$CLOUDNS_AUTH_ID" ]; then
-    _err "CLOUDNS_AUTH_ID is not configured"
+  if [ -z "$CLOUDNS_AUTH_ID" ] && [ -z "$CLOUDNS_SUB_AUTH_ID" ]; then
+    _err "CLOUDNS_AUTH_ID or CLOUDNS_SUB_AUTH_ID is not configured"
     return 1
   fi
 
@@ -125,6 +128,7 @@ _dns_cloudns_init_check() {
 
   #save the api id and password to the account conf file.
   _saveaccountconf_mutable CLOUDNS_AUTH_ID "$CLOUDNS_AUTH_ID"
+  _saveaccountconf_mutable CLOUDNS_SUB_AUTH_ID "$CLOUDNS_SUB_AUTH_ID"
   _saveaccountconf_mutable CLOUDNS_AUTH_PASSWORD "$CLOUDNS_AUTH_PASSWORD"
 
   CLOUDNS_INIT_CHECK_COMPLETED=1
@@ -168,12 +172,19 @@ _dns_cloudns_http_api_call() {
   method=$1
 
   _debug CLOUDNS_AUTH_ID "$CLOUDNS_AUTH_ID"
+  _debug CLOUDNS_SUB_AUTH_ID "$CLOUDNS_SUB_AUTH_ID"
   _debug CLOUDNS_AUTH_PASSWORD "$CLOUDNS_AUTH_PASSWORD"
 
-  if [ -z "$2" ]; then
-    data="auth-id=$CLOUDNS_AUTH_ID&auth-password=$CLOUDNS_AUTH_PASSWORD"
+  if [ ! -z "$CLOUDNS_SUB_AUTH_ID" ]; then
+    auth_user="sub-auth-id=$CLOUDNS_SUB_AUTH_ID"
   else
-    data="auth-id=$CLOUDNS_AUTH_ID&auth-password=$CLOUDNS_AUTH_PASSWORD&$2"
+    auth_user="auth-id=$CLOUDNS_AUTH_ID"
+  fi
+
+  if [ -z "$2" ]; then
+    data="$auth_user&auth-password=$CLOUDNS_AUTH_PASSWORD"
+  else
+    data="$auth_user&auth-password=$CLOUDNS_AUTH_PASSWORD&$2"
   fi
 
   response="$(_get "$CLOUDNS_API/$method?$data")"
diff --git a/dnsapi/dns_cx.sh b/dnsapi/dns_cx.sh
index e2f0f099..b3e04032 100755
--- a/dnsapi/dns_cx.sh
+++ b/dnsapi/dns_cx.sh
@@ -36,33 +36,18 @@ dns_cx_add() {
     return 1
   fi
 
-  existing_records "$_domain" "$_sub_domain"
-  _debug count "$count"
-  if [ "$?" != "0" ]; then
-    _err "Error get existing records."
-    return 1
-  fi
-
-  if [ "$count" = "0" ]; then
-    add_record "$_domain" "$_sub_domain" "$txtvalue"
-  else
-    update_record "$_domain" "$_sub_domain" "$txtvalue"
-  fi
-
-  if [ "$?" = "0" ]; then
-    return 0
-  fi
-  return 1
+  add_record "$_domain" "$_sub_domain" "$txtvalue"
 }
 
-#fulldomain
+#fulldomain txtvalue
 dns_cx_rm() {
   fulldomain=$1
+  txtvalue=$2
   REST_API="$CX_Api"
   if _get_root "$fulldomain"; then
     record_id=""
-    existing_records "$_domain" "$_sub_domain"
-    if ! [ "$record_id" = "" ]; then
+    existing_records "$_domain" "$_sub_domain" "$txtvalue"
+    if [ "$record_id" ]; then
       _rest DELETE "record/$record_id/$_domain_id" "{}"
       _info "Deleted record ${fulldomain}"
     fi
@@ -89,7 +74,6 @@ existing_records() {
   fi
 
   if printf "%s" "$response" | grep '"type":"TXT"' >/dev/null; then
-    count=1
     record_id=$(printf "%s\n" "$seg" | _egrep_o '"record_id":"[^"]*"' | cut -d : -f 2 | tr -d \" | _head_n 1)
     _debug record_id "$record_id"
     return 0
@@ -114,23 +98,6 @@ add_record() {
   return 0
 }
 
-#update the txt record
-#Usage: root sub txtvalue
-update_record() {
-  root=$1
-  sub=$2
-  txtvalue=$3
-  fulldomain="$sub.$root"
-
-  _info "Updating record"
-
-  if _rest PUT "record/$record_id" "{\"domain_id\": $_domain_id, \"host\":\"$_sub_domain\", \"value\":\"$txtvalue\", \"type\":\"TXT\",\"ttl\":600, \"line_id\":1}"; then
-    return 0
-  fi
-
-  return 1
-}
-
 ####################  Private functions below ##################################
 #_acme-challenge.www.domain.com
 #returns
diff --git a/dnsapi/dns_he.sh b/dnsapi/dns_he.sh
index 4d1973ad..7b854ead 100755
--- a/dnsapi/dns_he.sh
+++ b/dnsapi/dns_he.sh
@@ -19,14 +19,16 @@ dns_he_add() {
   _txt_value=$2
   _info "Using DNS-01 Hurricane Electric hook"
 
+  HE_Username="${HE_Username:-$(_readaccountconf_mutable HE_Username)}"
+  HE_Password="${HE_Password:-$(_readaccountconf_mutable HE_Password)}"
   if [ -z "$HE_Username" ] || [ -z "$HE_Password" ]; then
     HE_Username=
     HE_Password=
     _err "No auth details provided. Please set user credentials using the \$HE_Username and \$HE_Password envoronment variables."
     return 1
   fi
-  _saveaccountconf HE_Username "$HE_Username"
-  _saveaccountconf HE_Password "$HE_Password"
+  _saveaccountconf_mutable HE_Username "$HE_Username"
+  _saveaccountconf_mutable HE_Password "$HE_Password"
 
   # Fills in the $_zone_id
   _find_zone "$_full_domain" || return 1
@@ -62,7 +64,8 @@ dns_he_rm() {
   _full_domain=$1
   _txt_value=$2
   _info "Cleaning up after DNS-01 Hurricane Electric hook"
-
+  HE_Username="${HE_Username:-$(_readaccountconf_mutable HE_Username)}"
+  HE_Password="${HE_Password:-$(_readaccountconf_mutable HE_Password)}"
   # fills in the $_zone_id
   _find_zone "$_full_domain" || return 1
   _debug "Zone id \"$_zone_id\" will be used."