Hi All, I have a "Perfect Server 14.04" Ubuntu server setup with ISPConfig 3, and I have noticed many attempts to authenticate with my Postfix mail server from one particular host - onlinehome-server.com. The problem is that this particualr host always uses a different IP address, so fail2ban does not ban it. Is there any way in which I can deny all access to my mail server from onlinehome-server.com? I have been looking for a while on this, but I can't really find a definitive answer. I hope you can help. Alan
