User manual

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Figure 5.7.2
Difference:
MC/S is implemented on iSCSI level, while MPIO is implemented on the higher level.
Hence, all MPIO infrastructures are shared among all SCSI transports, including
Fiber Channel, SAS, etc. MPIO is the most common usage across all OS vendors.
The primary difference between these two is which level the redundancy is
maintained. MPIO creates multiple iSCSI sessions with the target storage. Load
balance and failover occurs between the multiple sessions. MC/S creates multiple
connections within a single iSCSI session to manage load balance and failover.
Notice that iSCSI connections and sessions are different than TCP/IP connections
and sessions. The above figures describe the difference between MPIO and MC/S.
There are some considerations when user chooses MC/S or MPIO for multipathing.
1. If user uses hardware iSCSI off-load HBA, then MPIO is the only one choice.
2. If user needs to specify different load balance policies for different LUNs, then
MPIO should be used.
3. If user installs anyone of Windows XP, Windows Vista or Windows 7, MC/S is
the only option since Microsoft MPIO is supported Windows Server editions only.
4. MC/S can provide higher throughput than MPIO in Windows system, but it
consumes more CPU resources than MPIO.
5.8 Trunking and LACP
Link aggregation is the technique of taking several distinct Ethernet links to let them
appear as a single link. It has a larger bandwidth and provides the fault tolerance
RAG362