1 drive, 2 servers not seeing the drive

[Sebretian]

I'm a beginner learning on the fly with our HP EVA 4100. I'm trying to see one drive on the SAN on two different servers but I'm having problems.

I've presented the drive to both my backup server and file server but run into two problems.
1. The drive shows up twice in disk manager, so I don't know which one to pick?
2. If I initialize and format the drive which was presented to both servers, I can't see the test file created on one, on the other.

Any help would be appreciated.

[marsh_1]

hi,

which OS is in use here, it sounds like you need multipathing software for it to stop you seeing the same disk down each path , if you want to share devices you should have some form of clustering / shared file system in place or you will corrupt your data.

hth

[Sebretian]

Backup server has Server 2003 SP2 and is a DL380 G3. File server has Server 2003 R2 and is DL360 G5.

Found and downloaded the MPIO software, thanks for that piece of the puzzle.

Any preference on which shared file system application?

[Steven Clementi]

The simple answer is...


you can NOT share a disk with 2 Windows Servers without the use of 3rd party software to provide file locking and such.

Do NOT share Windows disks.. you WILL lose data.

If you want to backup the file server drive, you need to present a snapshot of the original drive to the backup server, NOT the original drive. You will need a Business Copy license in order to do this.

Steven

[TTr]

You can not have a disk (volume/filesystem) mounted to more than one server concurrently unless you have special software running on the servers, such as node cluster, cluster filesystem etc. See some more comments here http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1311483

Looking back at your "backup" and "file" servers, what kind of backup software are you using and how much storage does your fileserver have? Maybe a simple backup "client" setup will be sufficient. Using SAN based snapshots or SAN disk copies is a well known backup solution but it is rather on the very expensive side.

[marsh_1]

hi,

clarify 'backup server' , is it a server you use that runs backup software or a standby to your file server ?
as steven has suggested take a look at business copy , overview here :-

http://h18000.www1.hp.com/products/storage/software/bizcopyeva/

or possibly windows clustering, a google on windows shared filesystem should get you going with other options.

fwiw

[Sebretian]

Good to know. I've been going about this all wrong from the sounds of it.

I'm getting pricing on Business Copy licensing from my vendor. Sounds like the price might be too steep though?

I'm going find a source/price for the Veritas Cluster File System and maybe go that route.

Backup software is HP Data Protector ver 6.0. The file server is a specialized laboratory medical application. The files are proprietary offline database files.

[Steven Clementi]

What kind of Tape Device do you have?

If it is fibre based, you can simply install the media agent on the file server and run backups directly to the tape device.


Steven

[Sebretian]

HP MSL6060 fibre to the SAN.

Thanks, I'll look into that. It may be an interim solution though. I have a linux server with a SAN drive to backup as well. It's going to happen more often and in the long term backing up the snapshot may be better. Have to see what price comes back.

[Steven Clementi]

"I have a linux server with a SAN drive to backup as well."

You can load the Media agent on the linux server as well, present the tape drives to the linux system and do direct backups.

You obviously can not use the same drive at the same time to back up both systems at the same time, but you can certainly back both up directly to the library.

You may need a license for DP... depending upon what you purchased initially.


Steven