Hi, I installed ispconfig 3 in a multi site environment. Everything - expect mail - is on the main server. On a second server the mail service is enabled. I used the debian 6 multisite tutorial - but am using debian 8. Now I recognised, that on the mailserver the bastille firewall seems not to be installed. I don't find the /etc/Bastille folder and no init-script in /etc/init.d Is there any way to post install the firewall? Or is it not necessary to have a firewall on a mail only server? Kind regards!!!