how to adjust iSCSI target boot information in Ubuntu 14.04?

[jrgruher]

We are doing some testing with iSCSI boot of Ubuntu Server 14.04 on a large bed of diskless clients. We installed one client to an iSCSI target “rbd_base”, using the Ubuntu installer to connect the iSCSI target, and then shut down and cloned the volume and attached to a second iSCSI target “rbd00”. We then booted a client from the cloned copy using iPXE, which begins boot OK, but when the client OS brings up the iSCSI initiator it still attaches to the original target:

iscsistart: Logging into rbd_base 10.0.0.3:3260,1

Boot succeeds, but obviously we cannot boot multiple clients this way, they’d all end up using the same "rbd_base" target instead of their own clone. How can I adjust to boot information to mount the new target, either by statically coding it, or better yet by having it use iBFT to just mount whatever target it was booted from?