We switched our mail server over from mbox to maildir a few months ago and couldn't be happier - the performance under normal load is incredible. However we now have a problem with backup.. Typically we would run tar on the mail server, sending its output to another server via ssh.. Like this: tar cfp - /home | gzip | ssh other.server (cd /backups && tar xfp -).. I have tried gzipping the stream on the source side, gzipping on the destination, and running without gzip, all three take an amazingly long time to complete (> 14 hours). Ours is a modest server with about 1300 users, about 300GB of mail total. The whole thing sits on hardware RAID-10, so I'm primarily guarding against a MAJOR hardware failure, a config blunder, or a hacker wiping out files. How do you guys back up your maildir? I've considered exporing the maildir with NFS and backing it up from another server.. Any opinions on that?