Offset (64)

[Claus Boehm]

Gents,

EVA 3K & EVA 4K in the past we've always set the offset allignment to 64 but since we've introduced a wast usage of ESX it seems that vmware do have a different approach to the usage of partition allignment same goes for MS SQL and Exchange. Can anyone pls. send comments also in reference to the loss of performance...how much is really lost in performance for not following the guidelines!?!

best reg,
-Claus Bohm-

[Ole Thomsen_1]

In ESX3 partitions created with VC2 (best practise) are aligned, otherwise has to be done manually.

VMware recommends that you align virtual Windows disks using diskpar.exe, just like you used to.

http://www.vmware.com/pdf/esx3_partition_align.pdf

Ole Thomsen

[Ole Thomsen_1]

According to VMware:

"The performance degradation of unaligned partition occurs during intensive I/O
workloads rather than on those with low to moderate I/O activity."

Ole Thomsen

[Nigel Poulton]

Although not ESX specific you may find the below thread interesting which we discussed a while ago -

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1036242

Hope this helps.

[Owen_15]

Hi Claus,

Just to add to the confusion of this 64 offset issue for the MBR. I defined the 64 offset using diskpart on a Windows 2003 SP1 server, running off a EVA5000 running VCS 3.028, and then went to format the disk, and was unable to do so! I deleted the defined disk, and recreated a default disk partition, and was then able to format the disk as normal.

I'm reasonably confident that we were not making a mistake with the diskpart command. But the results meant that it was impossible to create a disk on a disk defined with the offset, so we didn't and haven't used the offset and everything has been running fine for exchange, sql, and file servers attached to this san.

For ESX, I personally wouldn't worry about defining the offset.

Hope this of use.

Regards
Owen

[Bill Bocash]

I had the same problem with not being able to format after setting the offset, but found that you have to assign a drive letter first either through DISKPART command or Disk Management. Format work fine after that.
http://support.microsoft.com/kb/929491