Bind Hostnames to IP Address with Postfix?
I have a ISPConfig server setup running on CentOS, following the perfect server guide. How can I make it so that when an email is sent out, it goes by the IP address and hostname of the websites instead of the IP address and hostname of the server?
Also,Recently, it seems as though someone is routing spam through this server. Where is a good place to start to stopping this issue? I'm a bit new to server administration, thanks!