Initiator groups, or igroups, are tables of host identifiers such as Fibre Channel WWPNs and iSCSI node names. You can use igroups to control which hosts can access specific LUNs.
-i indicates that it is an iSCSI igroup.
-f indicates that it is an FC igroup.
-t ostype indicates the operating system of the host. The values are solaris, windows, hpux, aix, linux, netware, vmware, xen, and hyper_v.
initiator_group is the name you give to the igroup.
nodename is an iSCSI node name. You can specify more than one node name.
WWPN is the FC worldwide port name. You can specify more than one WWPN.
wwpn alias is the name of the alias you created for a WWPN. You can specify more than one alias.
-a portset applies only to FC igroups. This binds the igroup to a port set. A port set is a group of target FC ports. When you bind an igroup to a port set, any host in the igroup can access the LUNs only by connecting to the target ports in the port set.