I'm running a SYMPA lists server. I also host e-mail on a separate server for the users that want these lists. Primary MX records go to the Zimbra e-mail server, lists that reside on my Linux SYMPA server get forwarded from that e-mail server my SYMPA lists server.
My issue is a primary e-mail domain exists on SYMPA and on the Zimbra e-mail server where the e-mail accounts reside. Zimbra really doesn't matter its when SYMPA tries to send to that same e-mail domain. Description follows:
In postfix main.cf on the SYMPA server has "mydestination" includes the same e-mail domain that the recipients are in, example.com. SYMPA recieves an e-mail to firstname.lastname@example.org and then sends to recipeints at email@example.com. The problem is, it looks for the e-mail account or linxu account locally and doesn't find it. Getting the following error:
relay=local status=bounced (unknown user: "user1")
I've tried changing things I've found in Google and ServerFault but have not luck.
Tried transport_maps. In main.cf, I place this: transport_maps = hash:/etc/postfix/transport
I have the file transport within /etc/postfix/, it contains example.com smtp:[mxserverdomain.com]
When doing this, incoming mail to the list gets routed back out and loops. When I use sendmail to send mail directly to firstname.lastname@example.org it gets sent and doesn't get stuck looking locally. So, half its correct. However, then inbound mail gets routed out and sent back around to the server so many hops and fails. Rather than sending the mail to email@example.com, for example.
In the end I need to accept mail for the lists at this domain, and send to recipeints that are also on that domain. The issue is this domain matches the recipients I'm trying to send to.
The only other options, aside from hacking Postfix to work in the way I'm trying to and ignore the local domain, is to change that domain to something like lists.example.com and there will be none of this hang up about the domains matching and e-mail blackholing.
Thank you! Mike