HP MSA 1500 SAN and Windows Server 2003

[James Harris_5]

I am new to SANs. I have a newly installed HP MSA 1500 SAN. I have setup my RAID arrays through the HP Array Configuration Utility. From server A I was able to format the arrays under Windows 2003 server and assign drive letters and volume labels. I went to another server, server B, it sees the partitions but they do not have drive letters nor do they have volume labels assigned. If I look at the properties of the partition from server B it says it is raw space. If I assign it a drive letter, the same as I assigned under server A, it is usable but if I copy files to it server A does not see the files I copied from server B. Am I missing something?

[Steven Clementi]

James:

You can not reliably use shared storage amongstWindows Servers with having some sort of clustering/file locking utility in place.


If your servers ARE clustered with Microsoft Clustering AND your seeing your drives on BOTH servers, then you definitely have a problem as MSCS does not allow shared access to the same LUN at the same time.


Can you give us anymore information?


Steven

[Steven Clementi · Accepted solution]

That would be...

"You can not reliably use shared storage amongst Windows Servers withOUT having some sort of clustering/file locking utility in place."

Steven

[James Harris_5]

We originally were going to cluster the servers using the SAN. That idea was scrapped. We have four servers running windows 2k3 standard edition that will need to access the SAN. They will be running SQL 2000 standard edition. They will NOT be clustered. Do I have to cluster? Is there any other file locking utility we can use on the SAN?

So with out a file locking utility what I am seeing is normal?

[Steven Clementi]

If you can consider that "normal" then yes.


The 4 SQL servers need access to the SAM logical unit?


There are other third party products that can be used. One that comes to mind is PolyServ. I am not sure if it works with SQL at all, but it allows multiple Windows servers to access the same logical drive simultaneously.


Any reason to not use MSCS? (besides the cost of Server 2003 Enterprise).


Steven

[Uwe Zessin]

What you see is 'normal', but not correct.

Remember that 'SAN' in your environment simply means running serial SCSI protocol over a fibre channel infrastructure. At this level, the systems are simply dealing with blocks of data - they have no idea what a file system or a database is.

By default, the MSA1000 /1500 presents all LUNs / logical disks to all hosts. If you don't cluster, you must make sure that only a single host has access to its own LUNs. You do that by enabling the 'SSP' (selective storage presentation, also known as LUN masking) and tell the storage array which fibre channel adapter has access to which LUN. At this time I would rename the connections to a meaningful value and make sure that the operating system profile is set correctly.

[James Harris_5]

The reason to not use Clustering was the cost of 2003 Enterprise and SQL 2000 enterprise. I need 4 SQL 2k servers to access the SAN to store databases.

Can I setup SSP so only one server has control over the SAN? Will this fix my problem? From there all other servers can map to it and I can install my databases to the SAN from multiple servers?

I have one last question. I configured two sets of logical drives on the SAN. Under server 2k3 disk mangement I see 4 disks. Two of which I partitioned and assigned drive letters and volume names. Why is it showing 4 disks under disk management?

[Steven Clementi]

"Can I setup SSP so only one server has control over the SAN? Will this fix my problem? From there all other servers can map to it and I can install my databases to the SAN from multiple servers? "

SSP allows you to selectively present your logical disks to your servers. If you do not need your servers to access the same Logical Disk, you can Create 4 Logical Disks and selectively present one to each server.

"I have one last question. I configured two sets of logical drives on the SAN. Under server 2k3 disk mangement I see 4 disks. Two of which I partitioned and assigned drive letters and volume names. Why is it showing 4 disks under disk management?"

Do you have a MSA1000 with the Redundant 2nd Controller? If so, you will need a piece of software called Secire Path to handle multiple I/O paths to your storage. Alternatively, there is a "free" Multipath I/O driver available from HP.

The reason you would see 2 disks(in the OS) for each logical disk is because there are 2 physical paths to get to that disk from your server. Secure Path manages those 2 paths and presents 1 single drive to the OS.

Can you show a screen capture of the ACU's main page (after you click the MSA1000 controller)?


Steven

[James Harris_5]

We do have a second MSA 1000 and we will be installing secure path. Will I have to install the array config. utility on each server if I split the array into 4 logical drives and configure SSP on each server?

I cannot attach the screen shot. The file is 3.5 MB.

[Steven Clementi]

Can you convert the image to jpg? or maybe 256color BMP?


You will NOT need the ACU on ALL servers, only one server attached to the MSA1000. ACU is just a configuration utility. Having it on all the servers would make life a tad simplier, but it is not necessary.


Steven