iSCSI support for Compute/Nova

Nova currently supports persistent volumes using ATA-over-Ethernet (AoE). This is to discuss adding iSCSI support as an alternative.

Goals

Support high-end storage arrays Support OpenSolaris / Nexenta (?) Support Linux iSCSI target so that developers can get up and running quickly

Work is progressing in a launchpad / bazaar branch:

Currently the Linux iSCSI initiator & target are supported, and it works (though is not heavily tested)

Is the Linux iSCSI target stable (enough)? Is there a different target we should be supporting?

What are the requirements around LUNs / targets? Right now, each volume is exported as a target with a single LUN? Is this workable?

Which high-end storage targets should we support? Can we get EMC/NetApp/whoever to give us a loaner?

What extra functionality can they offer us that we can expose? Snapshots? Different storage classes? IOPS guarantees/throttling?