topic Re: LUN Provisioning while doing levelling in HPE EVA Storage

LUN Provisioning while doing levelling

apple — Sat, 17 May 2008 10:05:03 GMT

can we do lun provisioning while disk group is doing levelling (levelling in progress). hope to hear from you. thank you

Re: LUN Provisioning while doing levelling

Rob Leadbeater — Sat, 17 May 2008 12:19:40 GMT

Hi,

Yes you should be able to, although you haven't told us what storage system you're using.

Assuming an EVA of some sort, you'll probably find that the leveling operation will restart when you add a Vdisk.

Cheers,

Rob

Re: LUN Provisioning while doing levelling

apple — Sat, 17 May 2008 13:17:31 GMT

dear san storage guru,
we are using hp eva 8000. we can provision lun even the diskgroup is doing levelling. would like to seek your advice, if we have 200GB of vraid 5 available, can we still provision lun of 50GB? what is the best practise for minimum of disc that must left for any unexpected incident like one of the disc fail or anything (that is the only one i know of unexpected incident can happen to eva ;)). hope to hear from you.

Re: LUN Provisioning while doing levelling

Rob Leadbeater — Sat, 17 May 2008 15:36:21 GMT

Hi,

Yes, as far as I'm aware, you can create a new Vdisk whilst a disk group is levelling.

If you have 200GB of VRaid5 available in your disk group, then yes you can create a Vdisk of 50GB.

The best practice is to leave at least 5GB of raw (Vraid0) space available in the disk group.

Cheers,

Rob

Re: LUN Provisioning while doing levelling

IBaltay — Sat, 17 May 2008 15:45:34 GMT

Hi, one additional and very important thing according to the best practices besides the 5GB of free space is the SINGLE PROTECTION LEVEL (which means 2 virtual spares)

Re: LUN Provisioning while doing levelling

Peter Mattei — Sun, 18 May 2008 17:49:42 GMT

I suggest you read the EVA best practices whitepaper on:
http://h71028.www7.hp.com/ERC/downloads/4AA0-2787ENW.pdf

It also talks about allocation, headroom etc.

You will find more interesting HP storage whitepapers here:
http://h18006.www1.hp.com/storage/arraywhitepapers.html

Cheers
Pete