We have a server in our company DMZ (plain Ubuntu 8.10 with Postfix, no Zimbra). It speaks to the outside world for us and the Zimbra server stays within our normal network.
Is there any way to make Postfix on our "relay" server check against the Zimbra server for an access list of allowed recipients? My guess is that this is commonly asked, but I couldn't find it on a search. Sorry if this has come up before...
If anyone has done it, what method did you use?