improve stack detection

stack/host/mail/mailserver.yml

@@ -28,7 +28,7 @@ services:
     - ENABLE_AMAVIS=${HOST_MAILSERVER_ENABLE_AMAVIS:-1}
     - AMAVIS_LOGLEVEL=${HOST_MAILSERVER_AMAVIS_LOGLEVEL:-0}
     - ENABLE_DNSBL=${HOST_MAILSERVER_ENABLE_DNSBL:-0}
-    - ENABLE_FAIL2BAN=${HOST_MAILSERVER_ENABLE_FAIL2BAN:-0}
+    - ENABLE_FAIL2BAN=${HOST_MAILSERVER_ENABLE_FAIL2BAN:-1}
     - FAIL2BAN_BLOCKTYPE=${HOST_MAILSERVER_FAIL2BAN_BLOCKTYPE:-drop}
     - ENABLE_MANAGESIEVE=${HOST_MAILSERVER_ENABLE_MANAGESIEVE:-1}
     - POSTSCREEN_ACTION=${HOST_MAILSERVER_POSTSCREEN_ACTION:-enforce}
@@ -155,8 +155,3 @@ volumes:
   host:
     external: true
     name: ${HOST_DOCKER_VOLUME}
-
-networks:
-  public:
-    external: true
-    name: ${DOCKER_NETWORK_PUBLIC}