Try smtp with metallb

manifests/mailu/values.yaml

@@ -39,30 +39,16 @@ service:
     type: ClusterIP
     port: 80
     targetPort: 80
-  # smtp:
-  #   type: ClusterIP
+
+  smtp:
+    type: LoadBalancer
+    externalTrafficPolicy: Cluster
+    port: 25
+    targetPort: 25
 
 front:
   realIpFrom:
     - 192.168.10.0/24
-  externalService:
-    enabled: true
-    type: NodePort
-    externalTrafficPolicy: Cluster
-    ports:
-      smtp: true
-      smtps: false
-      submission: false
-      imap: false
-      imaps: false
-      pop3: false
-      pop3s: false
-      manageSieve: false
-    nodePorts:
-      smtp: 31025
-  nodeSelector:
-    kubernetes.io/hostname: k3s-master-1
 
 dkim:
   enabled: true
-