Thanks for the advice.
I don't use relay maps for the domain as the Internet doamin is shared betweent he MS Exchange server and the Postfix server. i.e I use MySql address lookups onthe Postfix server so it's easy to create addresses to forward email to different or multiple accounts. e.g sa...@xxx.com I don't think that multiple DNS records will work. (Although I may be wrong.) I use this technique, DNS round robin to evenly spread rdp connections to our terminal servers. My understanding is that a device does a DNS lookup and the server hands out each different IP address sequentially. Each device uses (caches) the first IP address it recieves until it's rebooted. i.e When the primary MS Exchange server went offline, Postifx wouldn't necessarally do another DNS looup and find the second record. Is it possible to setup multiple transport records wth different costs to a domain? This may be a solution. Cheers, Greg. > Greg Wilson: >> 2 different servers. How do I setup Postfix to >> automatically forward >> messages to one of the MS Exchange servers if >> the other oneĀ goes >> offline? > > Two options: > > A) Assuming that you use the "relay" transport in master.cf > (which you should if relaying mail from outside): > > /etc/postfix/master.cf: > relay unix - - n - - smtp > -o smtp_fallback_relay=[1.2.3.4] > > B) In the transport map, specify a hostname that resolves to TWO > IP addresses. Make up your own DNS or /etc/hosts entry if you > need to. > > Wietse >