HP EVA Array iSCSI Connectivity Option - Manual (Page 106)

Figure 55 iSCSI Initiator properties
Load balancing features of Microsoft MPIO for iSCSI
The features of MS MPIO for iSCSI include:
• Failover Only—No load balancing is performed. There is a single active path and the rest of the
paths are standby paths. The active path is used for sending all I/O. If the active path fails, then
one of the standby paths is used. When the formally active path is reconnected, it becomes active
and the activated standby path returns to standby.
• Round Robin—All paths are active paths; they are used for sending I/O in a round robin fashion.
• Round Robin with a subset of paths—A set of paths is configured as active and a set of paths is
configured as standby. I/O is sent in a round robin fashion over the active paths. If all of the
active paths fail, one of the standby paths is used. If any of the formerly active paths become
available again, then the formerly active paths are used. The activated standby path becomes a
standby path again.
• Weighted Path—Each path is assigned a weight and I/O is sent on the path with the lowest
weight. If the path with the lowest weight fails, then the path with the next lowest weight is used.
• Least Queue Depth—This is not supported by MPIO.
NOTE:
Failover policies are set on a LUN-by-LUN basis. MPIO support does not have global initiator for
failover settings.
106 Setting up the iSCSI Initiator for multipathing