Cluster File System / Replicated File System

[Nick Pavlica]

All,
  I'm trying to set up a group of redundant scp servers to back up my
data.  I was thinking that a cluster of servers with replicated file
systems would provide the redundancy that I would like.  I have a fair
amount of data and would like to be able to grow the storage as my
backups increase.  Is there a cluster and or file system replication
method that meets these requirements in FreeBSD?

Your help is appreciated!

--Nick