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Schedules and Mount Requests

Gavin Dunphy
Advisor

Schedules and Mount Requests

We have 5 SAN attached servers backing up to a SAN attached MSL library with three Ultrium 460 drives.

We would like to schedule them all for the same time and all to the same media pool of four tapes and allow the cell manager to control the queuing and tape drive allocation.

All have their own media agent, and all tape devices are set to "rescan" which seems to accurately reflect the media in each slot at the start of the backup process.

The problem is that we get regular mount requests for servers that have to wait. These cannot be confirmed until another barcode scan has been performed. Until then the slots have “?” against them.

It can happen to any server but we suspect it occurs when an additional tape is required from the pool.

I don’t know if we have made an error or if we are just expecting too much from the software. Is what we are asking possible and if so, can anyone explain where we might be going wrong?

Thanks in advance.
7 REPLIES
Gavin Dunphy
Advisor

Re: Schedules and Mount Requests

Forgot to add that we are using DataProtector 5.1, Sorry.
Kurt Beyers.
Honored Contributor

Re: Schedules and Mount Requests

Gavin,

You have to create 5 backup specifications for every server that is SAN connected.

In the first three backup specs, you can use the three physical tape drives. The two remaining backup specs will use a logical device that is already locked by another session if you start them at the same time. But with the lock names of the drives, these sessions will wait until the other session releases the tape drive.

As you have 4 tapes in the media pool, no mount request will occur, unless two tapes are or become full. It is better to configure the media pool to use a free media pool.

With this setup, your backups will run smoothly.

best regards,
Kurt
Gavin Dunphy
Advisor

Re: Schedules and Mount Requests

Thanks Kurt, but eventually we could have in excess of 15 servers writing to this library and since we have to take the used media off-site every day a pool of free-media is not ideal. What we really need is some way of performing an automatic rescan when the queued job starts.

Any idea's?
Kurt Beyers.
Honored Contributor

Re: Schedules and Mount Requests

Gavin,

If another session is already using the tape drive, you will get a message in the new session that the device is currently locked by another session.

When the first session ends, the new session will acquire the tape device and start with a barcode scan of the library.

Are you sure that your library is well configured for SAN based backups?

best regards,
Kurt
Gavin Dunphy
Advisor

Re: Schedules and Mount Requests

This will do a rescan. So if you look in Notifications in the gui and create a MountRequest notification, and get it to run the above command that might do the trick.

That's a fair question Kurt but I don't know what I don't know. Suffice to say that we are fairly new to the product and to SAN's in general.

All of the devices are detected and auto configured by the backup software so there is little further configuration that we can obviously do outside of scheduliong backups and restores.

The hardware was installed by HP engineers but the backup software was not.
Gavin Dunphy
Advisor

Re: Schedules and Mount Requests

All further discussion to take place in the Data Protector forum as it is becoming obvious that it is a software configuration issue, not a library issue.

http://forums1.itrc.hp.com/service/forums/questionanswer.do?admit=716493758+1111564264009+28353475&threadId=840035
Gavin Dunphy
Advisor

Re: Schedules and Mount Requests

Auto configuration through Data Protector of each host creates a library for each one, each one trying to manage it’s own resources. This is not the way to do it - further discussion in the above foru