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Best practice for VLS tape library configuration


Best practice for VLS tape library configuration

Hello all,


maybe there is somebody who has practice with VLS tape library configuration and can share best practice of this?

I know that this is very abstract request because it depends from many details, but can you advise how many virtual tape libraries to set up, how many drives, what size of virtual tapes is recomended and so on.

In our company we will implement VLS 9200 tape library. We will need file level backups, SQL and Oracle database backups.

We will backup about 200 servers, so I don't know what solution to chose.. to configure one virtual tape library and create more virtual tape drives and then dedicate some of them for file level backup and some for SQL and Oracle database backups or its better to create few tape librarys for each type of backups?

Also, I found that recomended virtual tape size is 5GB for tape, but I think it is too small, can you advice is it true or is better to create virtual LTO tapes as the standard LTO-3, LTO-4 or LTO-5 sizes?



Many thanks in advance for your help.



P.S. This thread has been moved from Tape Libraries and Drives to Disk-Based Backup. - Hp forum moderator

Best Regards,
Eemans Dany
Honored Contributor

Re: Best practice for VLS tape library configuration



Maybe this is not the best place to search for information on how to configure your VLS, but i wil try to help you on your way.

Much is depending if you are using deduplication or not.


Config without deduplication is easy, one store, one library can be used as a regular library.


Configuration with deduplication is another story.


First of all, you need to be aware that dedeplication on a vls 9200 is post process (meaning it runs after the backup and can take up to twice the time of backup. example, your backup is running 1 H, dedup can take up to 2 hours (can be sheduled to run in day time).


Next, create a storage pool with a library for each differant type of data, OS - "File-serving" - database (sql - oracle) - exchange - .....

Take special attention for encrypted files or aplications using encryption.

Encrypted files cannot be deduplicated and if possible store the in a separeted storage pool.

This allows you to achieve the highest deduplication within one storage pool.


To achieve the highest speed, you can use some simple guide lines.

Do not use multi streaming on one tapedrive, but use on stream on one drive (number of drives per lib is verry high). Disable hardware and software compression in the backup software, compression can reduce the deduplication ratio, compression used on the VLS is alowed.

Put in every server an FC card to connect directly to the VLS or make that you have enough media servers to load the VLS. If i am not mistaken, the VLS 9200 has a max performance of 600 MB/sec per node, meaning that you need minumum 5 Media server with a 1 Gb/sec (125MB/sec) to load (charge) one VLS node.


I hope this puts you on the way of using a VLS9200.




Frequent Advisor

Re: Best practice for VLS tape library configuration

Greetings Rolbraz,


Most of your questions are answered by folloowing document; the VLS Solutions Guide




There is a subtle balance in every environment between number of virtual tape drives and cartridge sizes.

More vitual tape drives allowes more streams into the VLS ( single data stream per drive) but the sooner a tape cartridge is full, the sooner the deduplication will become effective.



The VLS Solutions guide also contains backup application specific tips and best practices (DP, NBU, NW and TSM).


hope this helps,





Re: Best practice for VLS tape library configuration

Thanks for both posts, guys.

They really helped me to stay on the way... I'm reading the VLS guide and now I see that a lot of useful info there is here and with every page less questions I have.

Good luck for both of you!



Best Regards,