BackUp solution

I have a setup that is comprised of three dell R910 servers in a pool and running xenserver 6.1.

i had a problem with one host so now the post is only comprised of two hosts.

i have fixed the host that gave problems and upgraded xenserver to 6.2. 

2. three power connect switches 6224 stacked.

3.  two dell ps 6000 series equallogics for storage over a SAN.

Everything has been working well so far but i wanted to start running backups. So the organization acquired PHDvirtual. This has been installed but the challenge has been how to setup an iSCSI target or NFS externally. i have spare equallogics and NFS to choose from for the backup. I would like to do an offsite backup and replication. I was wondering what the best route would be to implement this backup solution with the equipment that I have mentioned.

My second problem is that as I have mention earlier I have two hosts running xenserver 6.1 in my live environment and I would like to join back the repaired host but I know this will not be easy because it is running 6.2. Is there a solution on how to join another version of xenserver to a pool with members on another version? Whats the best thing to do in my situation?