[Linux-cluster] requirements question

[linux-cluster-rhn at chaj.com]

We've got a fiber channel connection from two nodes to a single san storage
share (through a brocade). We're looking to export nfs from one of the hosts
with the other host as failover. As a test, I patched a 2.6.7 kernel and
compiled the necessary utilities according to
http://gfs.wikidev.net/Installation. I used LVM2 to create a logical volume on
the san device (/dev/sda1), gfs_mkfs'd the device according to the clustering
config that I made, and successfully mounted the lv on both hosts as a local
drive. Is it necessary for us to use LVM if the san is already doing the
raid/redundancy? What is the bare minimum in terms of daemons that we'd need
in order to run the above setup? I'm thinking it'd be something like:

ccsd
cman_tool join
clvmd
mount -t gfs /dev/sda1 /mnt/san-name

Also, what suggestions do you have for an automatic failover system for the
two hosts? I imagine some sort of heartbeat package. Thanks for your time.

Jim