tape library

[Dmitry Melekhov_2]

Hello!

I want to know for which purposes
can be used second mechanism in tape
libraries like 2/20 and 2/40?
For something like raid0 for tapes
or for raid1?

[Patrick Wallek]

The 2nd drive in a tape unit isn't for mirroring or striping. If you are using any 3rd party back up software to do your backups, like OBII, Legato Networker, Veritas NetBackup, etc. then all of these products have the ability to utilize both tape drives during the backup and to move tapes from the slots in the library to the appropriate drive in order to automate backups and make them run faster.

If you are not using any backup software that can control the tape unit in that manner then you are not really getting your monies worth out of the tape library.

[Dmitry Melekhov_2]

Sorry, I still can't understand what can
I do with 2 mechanisms.
For instance, I use OmniBack.
How can I use two mechanisms?

[Patrick Wallek]

OmniBack should be able to handle this automagically. You would need to make sure that OB knows about both tape drives. I would recommend reading the OB documentation on how to configure this. I don't use OB, so I can't give you specific instructions.

[A. Clay Stephenson]

Hi,

The simple answer is that 2 tape drives can make backups go twice as fast. You can configure many drives under OB2 but you have to have enough media agent licenses to run the drives at the same time. One very useful feature of OB2 3.x and up is that the drives in a single library can be connected to different hosts eventhough the robitics are controlled from one host. Everything works fine and the advantage of this is that you can spread the backup media agents over multiple servers to increase throughput or to locate the drives on the machines with the most data to be backed up so that network traffic is reduced.

The other important reason to have multiple drives configured is to allow media copy for offsite storage.

Regards, Clay

[Michael Tully]

Hi,

Questions similar to this do come into
the forum quite a lot. I would suggest
that to use the your tape mechanisms
correctly you need to have the ability
to move the tapes around before you
start configuring tapes from within
Omniback. First off can use the tape
robotic to move tapes? If the answer is
no then the attached white paper will
certainly help. It contains the info
on configuring your system devices for
this very purpose. If the answer is yes
and you omniback installed on your system
try and run this program to move tapes
around.

Try this command, which is what Omniback
uses to move tapes around the tape library.

# /opt/omni/lbin/uma -ioctl /dev/picker

To use two tape drives, Clay has rightly
pointed out the concepts.

A good place to start for Omniback
information is at the following link.

http://ovweb.external.hp.com/lpe/doc_serv/

Any further questions, don't hesitate to
ask

Michael

[Michael Tully]

Oops... forget to attachment..... ;-))