Adding 2nd IP to existing server

[cmcbride]

Our 5.0.16 Network edition running on RHEL5 is running great. But we're going to have to change the Internet IP number of the server. It's going to be a big migration task as we have 106 domains on it, and only about 25% of those domains do we have direct control over the MX records. The changes to the other domains will have to be coordinated.

As such I'd like to NAT both IPs to the same server. I can accomplish this network wise, but I need to know if there's anything I need to do to get Zimbra to work with it. What I'll have to do is configure a 2nd IP on the box, and then I'll have my firewall NAT from the new IP to the 2nd IP. At the same time I'll be keeping the original IP on the box. Due to firewall NAT limitations I can't have 2 different external IPs point to the same internal IP.

It'll look like this:

10.1.1.21 - original IP, NATed to 77.88.99.100 - Old Internet IP
10.1.1.22 - 2nd IP on the box, NATed to 22.33.44.55 - New Internet IP

So the question is, what changes do I need to make (if any) to get all the zimbra services to listen on both IPs on the server? All domain names and hostnames will stay the same.

Thanks.