[CentOS] NAS Storage server question

Hello all,

At our office a have a server running 3 Xen domains. Mail server, etc.

I want to make this setup more redundant.

There are a few howtos on the combination of Xen, DRBD, and heartbeat. That is probably the best way.

Another option I am looking at is a piece of shared storage, a machine running CentOS with a large software RAID 5 array.

What is the best means of sharing the storage? I would really like to use a combination of an iSCSI target server, and GFS or OCFS.

But the iSCSI target server in the CentOS repos is a 'technology preview'

Have any of you used the iSCSI target server in a production environment yet?

Is NFS and option?

Kind regards, Coert Waagmeester