Multi-machine mirroring choices

[Andrew Snow]

We have deployed an IMAP server running on Cyrus on FreeBSD 6.2, with a 
500GB UFS2 partition mirrored with geom_mirror and geom_gate across a 
dedicated 1gbps link.

It has proven to be very stable and reliable after appropriate tweaking. 
  The uptime of the mirror is usually 1-3 months, sometimes it seems to 
break randomly, possibly because our timeout is too low.  In any case, 
it doesn't take too long to rebuild at about 60mb/s.

(I recently tested the same solution with FreeBSD-7 and found it now 
goes at a full 100mb/s.)