==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release):
- Deployed with iRedMail Easy or the downloadable installer?
- Linux/BSD distribution name and version:
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):
- Web server (Apache or Nginx):
- Manage mail accounts with iRedAdmin-Pro?
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Hi Team,

I have a spam filter sitting on port 25 and dehind it an iredmail install with 1 domain. Now I had to get another email server up on a different domain but same external IP. I can get emails flowing in and out no issues but mail between the 2 domain fails.

Error is : mail for newdomain.com loops back to
    myself

Could someone advise me please?

I need to have 2 servers with each of its domain  ;-(

Rajbps