Lun Expansion

Question

I am expanding a LUN for Windows2003 Server that contains SQL2000 data and I havent used Diskpart to expand a drive before. While I can expand a LUN while the LUN is taking I/O what happens when I go to use Diskpart to expand the drive itself. I assume that I/O has to be stopped in order to expand the drive. Any tips or pitfalls to look out for?

Thanks,

Mike

Bowling1 · Answer

You 'can' expand the lun via diskpart while the server is taking IO; however, I personally do this during non-business hours. Windows 2000 and Windows 2003 (prior to SP1) sometimes doesn't work properly and the disk 'can' become unreadable until the server is rebooted.I personally wait for a low IO period just before or after work. If you don't encounter any problems after a few extensions, then you may feel comfortable doing this change during production hours. The process usually only takes seconds and no-one is the wiser, but when it doesn't work properly you can look really foolish - I've been bitten twice out of a +- 100 times, but the two times it didn't work as expected were on production file servers (ooops)...

AranH1 · Answer

The i/o does not necessarily have to be stopped but you should perform the operation during a low i/o period, i.e. after business hours. I have extended drives using diskpart on SQL servers without any issues so far.

Others in the forum have reported problems when performing the operation during production hours, so the amount of i/o is definitely a factor.

Also make sure you are on at least SP1 for Windows 2003, there were some improvements and fixes to diskpart that you will want in place.

Aran

AranH1 · Answer

Good point. What was the rev of FLARE you were on at the time. I don't know if the 'fast bind' feature in FLARE 24 would have prevented this problem, but that is definitely a good course of action: wait for the expansion LUN to be completely finished with the bind operation and wait for low i/o time.

dynamox · Answer

to add to what guys already mentioned ..i had an instance when i was expending a striped LUN ..and i did not wait for transitioning process to finish, so i went into diskpart and it was reporting the new space already available to be expanded ..so i went ahead and expanded the partition ..and guess what ..major corruption. I am not sure if anybody else has seen this, but i always do my diskpart expension when transitioning has finished in Navisphere.

dynamox · Answer

it was on CX600 running flare 19. Man ..did i hate that 600G LUN tape restore plus catching hell from application people. Lesson learned

Mpalumbo · Answer

So just to confirm, I can expand the disk using Diskpart once the expansion is complete and I can expand a drive without taking the drive offline. I would only be performing this operation during a maintenance window anyways so if something went sideways I would have time to recover.

Thank you all for you input,

Mike

dynamox · Answer

sounds like a good plan.

CLARiiON

Lun Expansion

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