[fche]

"Since moving my server to a data-center, the only downtime I had was when I needed to replace a disk."

By the way, there exist backup MX services - commercial or self-made, which would give you 100% incoming-mail uptime but without having to move or copy your server to a data center.

[jlgaddis]

Some hosts are doing away with backup MX hosts (including me/work) simply because a) any sane sender will retry for a period of at least several hours and b) sending via the backup MX is a common way for spammers to (attempt to) increase the chances of their mails getting delivered (e.g., due to lack of/decreased filtering on backup MX hosts).

[bhauer]

Thanks for the note! I'll definitely keep that in mind next time I evaluate my hosting environment. I expect to switch to a different data center eventually, and that would come in handy.