Istvan Prosinger:
> Hi, I hope this letter finds you well,
>
> I have Postfix behind NAT, and added one failover IP to the main router.
>
> I wanted to "get by cheaply" by just doing something like
>
> iptbales -t nat -I POSTROUTING -p tcp --dport 25 -j DNAT --to <backup ip>
>
> on the firewall machine.
>
> So, all well, the only problem is that Postfix in this case has a wrong HELO
> compared to the rDNS that I have defined
> for the <backup IP>
> It does throw a warning that the <backup IP> doesn't resolve to it's
> hostname, but I'm not sure if I can define some
> kind of helo_host_maps ;) to resolve this.
> At this point, I wouldn't mind if someone pinpoints me to the right direction.
Postfix does not compare the HELO command argument with forward or
reverse DNS information.
Wietse
