/etc/iscsi/nodes формат записей

погуглил вам

Portal Groups: iSCSI supports multiple connections within the same session; some implementations will have the ability to combine connections in a session across multiple Network Portals. A Portal Group defines a set of Network Portals within an iSCSI Network Entity that collectively supports the capability of coordinating a session with connections spanning these portals. Not all Network Portals within a Portal Group need participate in every session connected through that Portal Group. One or more Portal Groups may provide access to an iSCSI Node. Each Network Portal, as utilized by a given iSCSI Node, belongs to exactly one portal group within that node.

Portal Group Tag: This 16-bit quantity identifies a Portal Group within an iSCSI Node. All Network Portals with the same portal group tag in the context of a given iSCSI Node are in the same Portal Group.

Target Portal Group Tag: A numerical identifier (16-bit) for an iSCSI Target Portal Group.

Спасибо. Тоже яростно искал, но не преуспел :)