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I'm running ESX 3.5 currently, and about to set up 4.0 on a new HP EVA4400. Once the servers running 4.0 are up, I'll be migrating all of the 3.5 VMs over to the new datastores using Storage vMotion and then regular vMotion to get them on the 4.0 ESX hosts. The 3.5 hosts will then be upgraded to 4.0.

We had gone through a lot of problems with disk alignment on SAN, and I want to make sure that my VMFS datastores are properly aligned on the storage. Where can I check this? I'd like to check both my existing datastores, as well as the new datastores I'm creating on the new EVA.

Thanks for help!

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My google-fu was apparently lacking today. I've found this in the mean time:

Per that document, issuing fdisk -lu on your esx host will give you the information. partitions that have a start of 128 are correctly aligned, while those that start at 63 are misaligned.


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Now there is a catch to this. The alignment could be done at the storage level, which would make it invisible to the host. – mrdenny Sep 16 '09 at 0:38

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