[ Thanks to Falko
Timme for this link. ]
“This tutorial shows how to set up network RAID1 with the help
of DRBD on two Debian Squeeze systems. DRBD stands for Distributed
Replicated Block Device and allows you to mirror block devices over
a network. This is useful for high-availability setups (like a HA
NFS server) because if one node fails, all data is still available
from the other node. “