We help IT Professionals succeed at work.

Two public IPs, one router, one exchange server, WAN1 down, mail coming in on WAN2???

crp0499 asked
We have multiple public IPs from two diff carriers (comcast & at&t). All of those IPs come into the same building and terminate into the same router.  So, my router has two WAN ports.  WAN1 has the comcast IPs and WAN2 has the at&t IPs.

I have MX records set up on metrics of 10 and 40.  MX1 points to the comcast side.  MX2 points to the at&t side.

In my router, I have rules listening on each WAN port and sending port 25 traffic to me single exchange server (exchange 2010).  My hub transport is listening on both IPs.

I'm thinking that with this setup, if WAN1 fails, mail will still flow.



Watch Question

Director, Information Systems
Mail may flow out.  Whether or not it flows in depends on how your ISPs have their routing set up, how your DNS is advertised, etc.  If you want true redundancy/fault tolerance, you should speak with your ISPs about setting up BGP, etc.

For me it sounds perfect, i think it should work, is that configuration already in place??

If so just disconnect WAN1 and give it a few minutes and perform some email test to see if mail flows.