On 7/1/20 1:20 AM, Bill Cole wrote:
On 30 Jun 2020, at 15:40, Istvan Prosinger wrote:
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 ca
n 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.
Can't you just fix the DNS? Use a HELO name that resolves to both IPs
and give both IPs PTR records that point back to the name you use.
Fix the DNS? All reverse DNS should have an A record pointed back in the
DNS zone. This would be a real mess
best,
Istvan
