PS SQL Storage Best Practices

[fishmn]

Greetings,
We're a new customer to Polyserve SQL. We've been doing design work in advance of HP coming out to assist with the install. We'll be setting up an initial 8 node cluster (6SQL/2DTC) on HP BL460's using HP Virtual connect. Plan on using EMC powerpath and EMC cx FC storage. We'll using iLO fencing due to Virtual connect. We plan to install SQL2005/2008x64 on all nodes running win2003x64 on PS 3.6.2. this Cluster will house migrated pre-prod instances so we can be fairly aggressive about consolidation. We have targeted approximately 40 existing instances to migrate with between 3-7 TB of total data

I'm not finding much in the way of best practices for storage. We plan to use Mount points in windows for shared storage. LUN sizing for data, log, temp. How much Sharing of LUN's across instances if any is a good idea. HP touts this as a storage consolidation product so how do you folks accomplish this?

Thanks in advance for any input.

RAF

[Dan Tyndale · Accepted solution]

We have quite a lot of information on PolyServe hosting SQL. One of the best places to start

www.hp.com
Support and Drivers
See support and troubleshooting
PolyServe (case sensitive)

* Setup, install, and configure documents
* Troubleshooting documents
* Manuals

In addition to that, white papers. Some which might be of interest.
HP PolyServe Software for Microsoft SQL Server and SQL Server 2005 Database Mirroring integration white paper
HP PolyServe Software for Microsoft SQL Server best practices for disaster recovery white paper

Regarding best practices for storage, you should consult with EMC. Some general responses to your questions

*Mount points - good call, makes your backup strategy easier. Lun sizing for data, log, temp, depends on the application, room for growth. Follow the Microsoft recommendations for sizing. Regarding sharing of Luns, works well with PolyServe's DLM. It really depends on how you break that up. If it was me, my highly access databases would have EMC hardware stripping the disk (more disk spindles working together at HW level), perhaps even its own designated LUNs. On your lower activity databases, putting several on the same LUNs should not be an issue. Of course the disk carved up standard Microsoft 8K chunks, current miniport and Microsoft storport.sys drivers. As Microsoft never came out with SP3, follow KB 932755 to make certain your OS side of storage is running in best config. Very important - Make certain your blade servers are running current or one off from Firmware Maintenance CD and PSP.

Another big thing I see if with 40 instances, you want to make certain you enable memory limits for SQL. The goal is to have the sum of "max server memory" of all instances, running on a system, be less than the total physical memory on the system. Otherwise you can get a thrashing occurring when one of several of the SQL instances needing more memory when configured in a dynamic configuration. Regarding PolyServe for SQL 3.6.2, be sure to install HF1 BEFORE you install any instances on the machine.

[fishmn]

Hey Dan,

Thanks for the reply and detailed info. I think this product will be successful for us. I just hope that HP stays with it and doesn't abandon ship. We're really hoping that we can some of the promised ROI out of it.

[Emil Velez]

YOu can create a large filesystem (8K block size) and when you create the partition on the luns before you import them into polyserve check with EMC if they want you to align or offset the partition for that specific disk array.

If you put multiple instances on the same filesystem just put them in different directories. IF the filesystem runs low on room containing multiple instances you can just add a lun to the existing dynamic volume and the free space is then available. No downtime. That is part of the consolodation features.

You can move the tmp and log directories under each instance using SQL tools once the instances are virtualized to a directory on another Cluster mount point if you wish alot depends on how busy these instances are and whether you want that complexity.

Remember polyserve is hardware agnostic and disk array agnostic and you are using EMC disk arrays so there are alot of variables in creating best practices with this product.

Heck 4.0 is out for Windows 2008 if that is your option too. Since a new release just came out dont think it will go away quickly. The Other NAS solutions are not this good with SQL.