HP MPIO Load Balancing on MS Cluster

[Jason Langer_1]

All,

I currently have a Windows 2003 based cluster running SQL server. I am currently running into some possible I/O issues coming from the XP 1024 where the disk queue length spikes up to 100 and can stay constant for a bit of time. The system has dual HBA's.

We are thinking about setting up the "Load Balance" for the HAB's to Round Robin (currently configured for None). I have read some documentation that the load balancing feature is not supported on MS Clusters. Can anyone comment on if this is true and if so what is the reasoning? Also, any other suggestions in resolving the issue would be greatly appreciated.

Thank you,

-Jason

[Amar_Joshi · Accepted solution]

Jason,

I have similar setup with MS-cluster on Win2003, running SQL and I am using load balancing on MOIO. Surely supported.

I will strongly recommend you to enable Shortest queue length instead of round-robin. You can search google for more info on it. HPDSM supports another load balancing policy, called shortest_queue_size which is good if you have many different size of IOs going to storage.

My 2 cents worth.

[Jason Langer_1]

Amardeep,

Thank you for the response. Can I make this change on the fly or does it require a reboot of the system?

[Uwe Zessin]

I am not familiar with the current MPIO for XP and can't download it right now to check, but if it is any similar to the EVA version, it requires a registry change to both servers and a cluster shutdown, because the SCSI reservation mechanism is changed.

This should be documented in the installation notes.

[Jason Langer_1]

Uwe Zessin,

Thank you for the response. Would you happen to have a link to the installation documentation? I am coming into this enviroment second hand do not seem to have hard copies of it.

-Jason

[Uwe Zessin]

Sure, no problem.
This stuff is sometimes hard to find:

http://h20000.www2.hp.com/bizsupport/TechSupport/DriverDownload.jsp?prodNameId=421493〈=en&cc=us&prodTypeId=18964&prodSeriesId=421492&taskId=135

Documentation is either included in the software download and/or available via the "Manuals" link on the left side of this page.

[Amar_Joshi]

Jason,

Full Featured MPIO for XP v2.00.00 and above are supported in MS-Cluster, so prior to trying this make sure you have the right version of MPIO.

I have attached the Installation ref. guide. Look at the page 21, instructions are there to enable the load balancing and the enabling the correct policy.

HOPE THIS HELPS.