Hi

Im searching how to configure inside my postfix server for filter different subdomains using more than one relayhost. In my case I have 4 subdomains and I need to create other "test.mydomain.com" appointing to a new relayhost. This is a internal process to change the antispam appliance.

Any idea of how to make this?

Thanks

Postfix is a wonderfully configurable MTA. Your goal, however, may be a little non-standard. Consequently, it may take some tinkering to get it correct. Having said that, I think you should be able to use virtual transport and alias mapping to direct your sub domains to the desired hosts.

The first place to look would be the Postfix documentation pages. They are extensive with examples of a lot of different setups. Here is a link. At first glance, the virtual_alias_domains sounds like it might be close to the mark as it mention mapping addresses to joe@somewhere and jane@somewhere-else.

I'm not really sure about your setup - you want to add a 5th virtual domain and forward this to another machine?

Having different relayhosts for different domains is usually specified in the transport table (man transport).