============ Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.3
- Linux/BSD distribution name and version: Debian 8.3
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): My Sql
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro? No
- Related log if you're reporting an issue:
====

Hi -

I have 2 iredmail servers, one is the primary domain a.com , and the 2nd is configured as a backup MX for domain a.com.  What I'm seeing is that the spammers are trying to relay directly off the backup MX causing fail2ban on the primary MX to block the backup MX.

Here's an output example from the backup MX mailq:

759E01C0D4    20880 Tue Feb 16 13:41:06  Ybarra_Annette@lettrepromotionnelle.com
         (connect to a.com[45.1.2.3]:25: Connection refused)
                                         dude@a.com

Here's an output example from the primary MX iptables:

Chain fail2ban-postfix (1 references)
target     prot opt source               destination
REJECT     all  --  backupmx.com       anywhere             reject-with icmp-port-unreachable

I tried white listing the backup MX with the check_client_access parameter in postfix, but that didn't seem to work.

Is there a way to harden the backup MX so it rejects the spam like it does on the primary or to always allow the backup MX to connect to the primary without fail2ban locking.

Thanks!