Tape Library Configurations - Best Practices

[Adnan_M_F]

Hello,

I've configured the below in my environement lately:

- 4 Media Servers (A,B,C,D) with A being master as well. Each media server has its own PureDisk storage and connected to 3 TLs as below.

- 3 Tape Libraries (X, Y, Z with 4,2,1 drives respectively, a total of 7 drives)

For tape library configurations, I've performed the below:

a) Single "Storage Unit Group" with each 12 STUs, each representing the 4 Media servers connected to the 3 TLs.

b) 5 Different "volume pools" for different applications like Oracle, SharePoint, Exchange, etc.

c) About 9 SLPs, configured to reflect the various PureDisk connected to the various TLs.

d) All 3 TLs are managed by single robot control host, the master/media server "A".

My questions are as follows:

1) Would there be a better way to configure the above?

2) Currently I see that one of the media server "C" connected to 2 TL, uses  both but not all the drives. No other tape jobs with other media servers are on. But tape jobs in "C" are queued rather than using the available 2 drives. Am i missing some configuration which limits number of drives?

3) How can i make sure all my drives are running at best possible performance level and are utilized simultaneously, apart from proper job scheduleing :)

Regards,

Adnan

[Even]

Test the performance of each component, tapedrive from network, from disk etc. so you know what to aim for.

Way to complex configuration to tune. Keep it as simple as possible. Use as few drives as possible, meaning: not more than you can keep up to speed. Do not forget to use multiplexing if you can. Do not use more retentions and volume pools than neccesarry. If data are duplicated/rehydrated from dedup to tape, this stream will not utilize fully one tapedrive. 

[Nicolai]

I see no reason for using different volume pools. Use one. Many volume pools reduces the efficiency of the tape drive.

A oracle backup could be waiting for a free tape drive, while SharePoint is running, if we assume MPX is configured. Using one volume pool both Oracle and SharePoint would run concurrent

[Adnan_M_F]

Thank you Even & Nicolai.

I did try out multiplexing but it seemed to fail. I will look into it again. Just read that there are 2 multiplexing options which need to be set (i.e. in the policy schedule "Media Multiplexing" & in storage units by "enabling multiplex" and specifiying maximum streams per drive. didnt konw about the "media multiplexing" option earlier.

The reason for the different pools was to ensure backup data belongimg to certain applicaiton is written on same cartridge & also track the number of cartridges utilized by different applications each week. Or is there another way?

One of the options in "Volume Pools" is "maximum number of partial media". Now my understanding is that the number specified here will keep media partially used to only that number and hence will save on cartridges. For example if the max. partial media is set to 2, then at any given time only two media will be "Active" and will be written on unless they get "Full". Please correct me if i m wrong.

Thank you.