Single iSCSI taret & 2 initiators...

"iSCSI imposes no rules or restrictions on multiple computers sharing individual LUNs; it leaves shared access to a single underlying filesystem as a task for the operating system."

That is precisely your problem - OS X provides no control of how the 2 initiators write to the LUN and so data corruption is highly possibly - probable even.

Consider an external HDD with firewire interface which often come with 2 ports to enable daisy-chaining. You could simultaneously connect the drive to 2 separate macs such that both use the disk and there would be no protection from both macs writing to the same location. That's what you have with one LUN and 2 initiators

Applications such as VMWare have controls built-in to deal with this scenario. There are also specialised File Systems designed to support this, but not easily supported on Mac

Networking protocols such as CIFS and AFP are specifically designed to enable simultaneous access to shared storage - iSCSI is not

Note: The developers of the initiator you are using also provide software that supports what you are trying to do - but it is substantially more expensive

http://www.studionetworksolutions.com/p ... l.php?pi=8