> We are looking at possibly colo'ing an exchange server to do a store and > forward in case our main exchange server/datacenter has problems.
Howzitgo? In theory, theory is the same as practice. The theory in this case being that with a secondary MX or other disconnected gateway architecture there will be next to zilch work for IT dept. and zero mail lost even in an extended disaster. At first this seems like a good idea. Then, in practice, you run into the operational issues Rob talked about. There's also a pretty good chance at some time that such a setup will start generating spam in the form of blowback. There are other issues too if you're willing to look into it. But consider the fine points of SMTP delivery: if your Exchange was unavailable for even a couple of days, you will still get nearly all the mail in a few hours after the system is back online. This is because senders will queue and try to send for about 3 days in most cases. What about the mails that aren't part of this "nearly all?" OK, for those few stragglers (or in the case that you're down for a week all mail) that don't get delivered, consider that every sender will get a message saying their mail wasn't delivered and they will resend or call or whatever. You will likely find that they've probably already called when their system warned them after half a day that their mail hasn't been delivered yet. For the smaller or even medium sized shop a $25/mo. dialup line as backup connectivity starts to look pretty attractive; you can transfer a lot of mail on a 56K connection. Adding an imaging based backup solution like Acronis and you're golden. ~JasonG ~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~ ~ http://www.sunbeltsoftware.com/Ninja ~
