I have some dedicated VPS's added to my ispconfig farm for clients of mine. As these servers are new and have NO reputation some email will be blocked here and there even though DKIM etc is in place. Now my idea is to relay the extra mailservers to my own mailserver that already has a good reputation. The question: Does all the rules apply before the email is relayed to my smtp server? authentication spam etc? The reason: I dont want to lose my good reputation score
I may not completely understand what you're asking either, but I think you are wondering how authentication of the mail accounts on your new servers and spam scanning of their email comes in to play when also relaying through your other server? By "etc." maybe you mean virus scanning? Authentication is pretty straightforward, the mail accounts authenticate with the new servers to send mail, then that server handles delivery; typically there would be no authentication between these new servers and your older, established mail server, you would just configure the former to relay and the latter to accept all mail from those servers. Mail headers will then indicate that as well (show an authenticated user in the Received header from the first server, with additional Received headers showing the mail traversing your old server). As for spam and virus scanning, with amavis on a default ISPConfig configuration (eg. via a debian Perfect Server install, without customizing), mail will pass through amavis on port 10026, and it appears for mail to non-local domains (ie. which will be relayed in your case), will be virus scanned and also spam scanned, though the default spam thresholds are so high (tag at 20, mark/kill at 60) it is almost the equivalent to not spam scanning.
