Added needed servicename parameter for statefulset

charts/postfix/v0.1.0/templates/app.yaml

@@ -8,6 +8,9 @@ spec:
   {{- if not .Values.autoscaling.enabled }}
   replicas: {{ .Values.replicaCount }}
   {{- end }}
+  {{- if (eq .Values.postfix.kind "StatefulSet") }}
+  serviceName: {{ include "postfix.fullname" . }}
+  {{- end }}
   selector:
     matchLabels:
       {{- include "postfix.selectorLabels" . | nindent 6 }}