ZFS for Cyrus IMAP storage

[Gary Mills]

There was a question earlier regarding ZFS for Cyrus IMAP storage.  We
recently converted to that filesystem here.  I'm extremely pleased
with it.  Our server has about 30,000 users with over 200,000
mailboxes.  It peaks at about 1900 IMAP sessions.  It currently has 1
TB of storage with about 300 GB in use.  The server is a Sun T2000
with 16 GB of memory, running Solaris 10.  It uses iSCSI to provide two
500 GB devices from our Netapp filer.  Disk redundancy is all on the
Netapp because it's currently superior to that provided by ZFS.

ZFS is fully POSIX compliant; Cyrus is quite happy with that.
Performance is excellent.  The full backups go much faster than they
did when we were using UFS on a pair of locally-attached RAID-5
arrays.  The ability to expand the storage pool simply by adding more
devices from the Netapp is very appealing.  No longer will we have to
move mailboxes from one partition to another.  The snapshots are
wonderful.  We keep 14 daily snapshots, instead of doing daily
incremental backups.  I can certainly recommend ZFS for Cyrus.

-- 
-Gary Mills-    -Unix Support-    -U of M Academic Computing and Networking-