DSU Fragmentatation

[Backup_Man]

Hi

I am really interested to hear about how you all deal with fragmentated DSU's within your Netbackup enviroments and what stratergies you use to keep this problem to a minimum??

Currently i have 5 media servers in my enviroment which all have 4 x 4TB Luns FC attached . The DSU's are fragmented and causing slow performance. Obviously i could do a defrag on one of the LUN's and leave for 2 weeks to complete but that takes too long? Otherwise, my other option is to remove any images from the LUN and then format the DSU.

How do you all deal with this problem???

Also, how much storage do you all present to one media server??? Is 12 TB too much??

Thanks

[Stumpr2]

Is this a trick question? The backup image could go on 27 phyisical platters. It is already fragmented when it is written? isn't it?

[Backup_Man]

Sorry. No its not a trick question, you dont understand the question

Say you have a Media Server with 4 TB of SAN storage for disk staging. This storage is RAID group on a clariion disk array over say 14 spindles

You use this storage unit for 6 months for staging data, this dsk staging area will become fragmented very quickly. and therefore performance will drop dramtically. If your use to writing to this LUN at 40mb/sec and then it drops to 10mb/sec, backup times will increase etc

How do you deal with this?? One of the methods i suggested before