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11 PS Series Architecture: MPIO with Devices That Have Unequal Link Speeds | TR1105 v1
3.5 A complex example using variable speed host interfaces and
limiting total connections per volume
Variable speed host interfaces are interfaces where the bandwidth used can be set to less than the actual
link speed of the device. In this case, the lower bandwidth set on the interface determines the number of
connections rather than the maximum speed that the interface is capable of supporting. The MPIO
software attempts to maximize the bandwidth available. For example:
 A PS Series SAN consisting of 3 members, each with 1 x 10Gbps port enabled
 A host, with 2 x 10Gbps interfaces, with a variable bit rate set to 3Gbps on each, with the Max iSCSI
connections per member/volume = 2 (default value) and Max iSCSI connections per Volume = 4
(default = 6),
A configuration such as this results in four iSCSI connections made by the MPIO software from the
host to the three members. Two of the iSCSI connections from the host interfaces will be to the same
PS Series group member's single interface, as the PS MPIO software will attempt to utilize as much
array bandwidth (up to 10Gbps) from the available two 3 Gbps interfaces on the host, subject to pool
limits and the host' max iSCSI connection limits.