Multi-Path I/O has been around for some time in SnapDrive and is fairly popular in the Fibre Channel arena. With the release of SnapDrive 3.2 and Microsoft's iSCSI Initiator 2.0, MPIO is now available for iSCSI as well as FCP implementations.
This IBM Redpaper addresses commonly asked questions about planning and implementing Multi-Path I/O support with the IBM System Storage N series. It is not meant as a replacement for product documentation but rather an aid.
Table of contents
MPIO (Multi-Path I/O) information
Does IBM N series support the Microsoft MPIO driver for iSCSI connections?
So how do I enable MPIO for iSCSI or FCP?
I'm not doing MPIO now but might in the future. Should I go ahead and install the MPIO drivers?
Can I configure iSCSI MPIO with SnapDrive 3.1, 3.1.1 or 3.1.1R1?
What else do I need?
During the installation of Microsoft iSCSI 2.0, there's a check box for MPIO. Should I select that?
How can I tell whether the system has the Microsoft iSCSI MPIO DSM loaded or the N series MPIO DSM loaded?
What do I do now to get iSCSI MPIO configured?
I have a pair of HBAs installed with MPIO configured. Should my throughput increase as a result or is one HBA there just for failover?
I have added another FCP Initiator to my host but SnapDrive does not indicate paths from it to the target filer. Do I have to disconnect and reconnect each LUN to get SnapDrive to “see” the new paths?
Does MPIO work with iSCSI and FCP boot LUNs on Windows? In other words, if I boot off of a LUN on a filer, can I then perform MPIO on that LUN?
Other recommendations for MPIO