Fix relay issue

mail/openeuler.org/config.yaml

@@ -67,11 +67,11 @@ data:
     dc_other_hostnames='openeuler.org;'
     dc_local_interfaces=''
     dc_readhost=''
-    # NOTE: wildchart is used here, but it's not safe at all.
-    dc_relay_domains='*'
+    # NOTE: Do not used wildchart here, use `dc_relay_nets` to control which IP is valid.
+    dc_relay_domains=''
     dc_minimaldns='false'
-    # NOTE: wildchart is used here, but it's not safe at all.
-    dc_relay_nets='*'
+    # NOTE: Please update this into the correct CIDR of the cluster pods.
+    dc_relay_nets='172.17.0.0/16'
     dc_smarthost=''
     CFILEMODE='644'
     dc_use_split_config='true'

mail/openeuler.org/mtaservice.yaml

@@ -9,7 +9,8 @@ metadata:
     kubernetes.io/elb.id: f4efa65e-8e29-492b-8408-92b8ad20d6aa
     kubernetes.io/elb.lb-algorithm: ROUND_ROBIN
 spec:
-  externalTrafficPolicy: Cluster
+  #We need set this into 'Local' since we need get the client IP for relay excluding.
+  externalTrafficPolicy: Local
   loadBalancerIP: 159.138.46.20
   ports:
   - port: 25