I've no experience with iscsi. In fibre channel I've used multipathd to manage redundant HBA's. I've used Ethernet bonding to manage redundant network cards. Suppose I have two network cards attached ...
06:00.0 Ethernet controller: MYRICOM Inc. Myri-10G Dual-Protocol NIC (rev 01) 07:00.0 Ethernet controller: MYRICOM Inc. Myri-10G Dual-Protocol NIC (rev 01) They are ...