NetApp
7-mode/HA pair/V-Series : Configuration : Protocols : iSCSI : Understanding iSCSI : Target portal group management

Target portal group management
A target portal group is a set of one or more storage system network interfaces that can be used for an iSCSI session between an initiator and a target. A target portal group is identified by a name and a numeric tag. If you want to have multiple connections per session across more than one interface for performance and reliability reasons, then you must use target portal groups.
Note: If you are using MultiStore, you can also configure non-default vFiler units for target portal group management based on IP address.
For iSCSI sessions that use multiple connections, all of the connections must use interfaces in the same target portal group. Each interface belongs to one and only one target portal group. Interfaces can be physical interfaces or logical interfaces (VLANs and vifs).
Prior to Data ONTAP 7.1, each interface was automatically assigned to its own target portal group when the interface was added. The target portal group tag was assigned based on the interface location and could not be modified. This works fine for single-connection sessions.
Starting with Data ONTAP, you can explicitly create target portal groups and assign tag values. If you want to increase performance and reliability by using multi-connections per session across more than one interface, you must create one or more target portal groups.
Because a session can use interfaces in only one target portal group, you may want to put all of your interfaces in one large group. However, some initiators are also limited to one session with a given target portal group. To support multipath I/O (MPIO), you need to have one session per path, and therefore more than one target portal group.
When an interface is added to the storage system, each network interface is automatically assigned to its own target portal group.
In addition, some storage systems support the use of an iSCSI Target expansion adapter, which contains special network interfaces that offload part of the iSCSI protocol processing. You cannot combine these iSCSI hardware-accelerated interfaces with standard iSCSI storage system interfaces in the same target portal group.
Configuration > Protocols > iSCSI
You can use the iSCSI window to start or stop iSCSI service, change a storage system iSCSI node name, and create or change the iSCSI alias of a storage system. You can also add or change the initiator security setting for an iSCSI initiator that is connected to your storage system.
Tabs
Service
You can use the Service tab to start or stop iSCSI service, change a storage system iSCSI node name, and create or change the iSCSI alias of a storage system.
Initiator Security
You can use the Initiator Security tab to add or change the initiator security setting for an iSCSI initiator that is connected to your storage system.