Q. I'd like to share iSCSI storage with our 3 node web server cluster. How can multiple systems access a single iSCSI LUN under Linux operating system? Can I connect multiple servers to a single iSCSI LUN?
A. Short answer - no it is not possible.
Long answer - It is possible to access a single iSCSI LUN using cluster aware file system such as GFS or OCFS2. You can also use NFS or Samba for sharing file system. iSCSI provides no file locking. This may result into serious data corruption. To share LUN simply use cluster aware file system.