PMG and multi WAN


Well-Known Member
Jan 6, 2013
Scenario: Zimbra mail server behind Proxmox Mail Gateway in a LAN with two Internet connections in load balancing mode.

In this case the VM running the Proxmox Mail Gateway must have two NICs, one with public IP from the first ISP and one with public IP from the second ISP. And these IP must be set in the MX and SPF records of the DNS. Right?
I would probably do the distribution on the firewall/router connected to both internet connections - and create fitting NAT rules that route traffic on port 25 to the internal address of the PMG (and keep the PMG with only one NIC)

It is possible to create a second routing table and direct traffic accordingly in linux as well -but it's quite a bit of configuration and makes debugging more difficult (if you want to take that road - just look for two upstreams/internet connections on Debian (or linux in general) - the howtos should apply to PMG as well)

I hope this helps!
Ok. I this case the most important thing will be to correctly set the Outgoing NAT, to be sure that email comes out from one of the two IP configured in the DNS ...

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