I have a question on planning. Recently, I got a request to create 2 625GB Luns (clariion cx-240), FC Connected, to ESX server 4.0 (four new hosts). I don't know the application they would be running. However, I only had option to carve luns from raid 5. All FC disks, and i did not look for number of disks in the raid group just looked for capacity. These existing raid groups are used for many applications -DB2, SAP and other. would that make any difference b'cause i am taking luns from 20 RGs.
This is what I did, created 2 metas. Now, to start with the raid groups I had, like I said, all RAID5. So I decided to take 10 luns of 63GB and another 63GB with 10 luns. Then I created a meta for each and allocated the storage, assigned all the four hosts to that SG.
So I've presented 630 + 630 i.e a total of 1260 GB and the request was for 1250GB. Now my question is, is it the best practice to convert the GBs to block and allocate, so that exact requirement is fulfilled.
Another thing I want to clarify is, I decided to take luns small in size so that the I/O impact is not much. Could I have done some thing better while provisioning this requirement? (lun size while creating meta)
Please advise me so that I can make sure I allocate the best way next time...
Thank you for reading!
I want to serve my customer the best way and I am a novice, so please don't ignore my post and help me understand the best way if there's any, so that I can work more intelligently next time.