> -----Original Message----- > From: owner-postfix-us...@postfix.org > [mailto:owner-postfix-us...@postfix.org] On Behalf Of J.P. Trosclair > Sent: Thursday, 26 March 2009 11:05 AM > To: mouss+nob...@netoyen.net > Cc: postfix-users@postfix.org > Subject: Re: [maybe OT] postfix HA > > mouss wrote: > > I am trying to "collect" methods to setup postfix in an HA > > configuration, for "outbound" relay (no MUA involved). a use case is
> > using multiple postfix boxes to relay mail out for one or more > > exchange servers. there are many possibilities. which one is > > "good/recommended/easy/blahblah"? This is somewhat off topic since the > > problem is mostly on the client (exchange or other) side rather than > > postfix. but I think this is a real need. and if I get enough infos, I > > can aggregate them and submit that as a howto/readme. We have an Exchange infrastructure (9 servers) with two Postfix servers as the sole outbound MUAs in geographically-diverse sites. All we use is simply a DNS round-robin alias that points to both Postfix servers, which the external STMP connector for the Exchange org (and all the servers inside it) is configured to use. Fairly standard setup - some round-robin implementations can also do some smarts to determine which hosts are actually up before returning the IP to the enquirer. Since these are real SMTP connections, if the first host that is resolved via the round-robin is unavailable, the Exchange server will simply retry until get gets a host that replies. If you want to direct outbound traffic via a specific Postfix server/round robin alias for specific Exchange servers, and perhaps another group of Exchange servers via a different outbound route, there is no problem with setting up more than one SMTP connecter in the Exchange org, and adding the appropriate servers/round-robin alias to that specific SMTP connector.
