Open Source SAN

I bought two Dell R200 because they was extremely cheap.

My target is Open Source SAN with active/passive setup.

Now i was wondering what RAID-level I should go for.

I will use 1TB SATA-II disks.

1) RAID-1 in both servers and mirror each other with DRBD.
With this setup i have like double RAID-1 so i lose lots of disk space.
4 disks -> 1TB

2) No-raid at all and i will mirror data with DRBD.
4 disks -> 2TB

Then there is change to go for RAID-5. Theres enough space to put third disk in that case

3) RAID-5 in both servers. Mirrors data with DRBD.
6 disks -> 2TB but more performance.

But in every setup i lose space more then i would like to.

Actually i dont need space more then 1TB, but i would like to get best possible redundancy and most space available i could.

Also need to remember that those servers does not support hot-plug HDs so in case there is disk-failure i need to be able to shutdown one server and iSCSI should still be up and running.

Of course theres change to make it active/active.

I was thinking that if I go for the RAID-5 I will make LVM-VG on both nodes (san-vg1 and san-vg2) and use it 50/50.

In case of fail both VG's will be used from working node.

Im going to use Debian Lenny I guess..

I was looking for OpenFiler because of the GUI, but im familiar with Debian and have always done everything from cmd.