Sharing MSL library between 2 SANs

[Rob Crooks]

I currently have an MSA1000 dedicated for one AlphaServer and another MSA1000 dedicated for a group of Windows servers using the same SAN fabric. My question concerns "sharing" a FC connected tape device. I know that I can't interconnect/share an MSA, but if I buy an HP library such as the MSL6026, can I "share" it with both VMS and Windows?

I know I can't use it at the same time, but I am only talking about doing a VMS backup at 6 pm and then a Windows backups at 12pm so they would never try to access the tape at the same time.


Thanks

[Mark Poeschl_2]

Yes, we've done exactly that by creating an alternate configuration in the SAN switch and then switching between the configs using the 'cfgenable' command. It's been completely transparent to all the servers on the SAN to date.

Leaving the MSL accessible to both sets of servers all the time "MIGHT" work, but I think you'd likely run into issues.

[Rob Crooks]

It nice to see that I'm not trying something COMPLETELY outside the box.

When you change your config as you say, it this a scripted operation? Or does someone have to manually change it everytime?

Forgive my ignorance, but what exactly does "cfgenable" do? I have never played with the SAN switches in my MSA.


Thanks for the info. :)

[Marino Meloni_1]

A library in SAN may be used by several OS, the only problem is that you should send command to the robot or single tape from one Host at a time.
Usualy backup application take care of this, the cel server is the one who decide which host should backup at that time and usualy manage the robotic controller.
If you plan to do backup manualy, all this management should be done by yourself, but there should not be any problem if the library in on the same SAN

You can found all the compatibility here:
ftp://ftp.compaq.com/pub/products/storageworks/techdoc/ebs/EBSMatrix-0306.pdf

[Torsten.]

I guess Mark is switching the SAN configuration like this:

1. VMS can see and access the lib, Windows can't

2. Win can see and access, VMS can't

It's always safe to prohibit one of the servers the access. I'm not sure, but I guess this is far out of a supported solution. Because the systems may protest because of missing devices...

A good solution IMHO will be to give one server access to the robot and the first drive, the other server only access to the other drive. Best solution will be an integrated backup solution with management and storage agents.