Saw there was a thread on setting the MPIO configurations correctly. Last week Brian Musson and I created a script that will install & configure open-iscsi, multipathd, and the scsi utils. The only thing the user will have to provide are the names of the iSCSI NICs (eth1, etc) and the iSCSI discovery address. Once the configuration is done, it will prompt for which target to log into.
It has been tested against CentOS 5.9, CentOS 6.3 & 6.4