Which is better for data... several virtual disks or one big virtual disk?

[REALM]

For a Windows 2003 VM on ESX 3.5, what is technically better to present? Is there anymore reliability or risk with one or the other?

All luns are presented from a raid5 san.

C: Drive it's it's own virtual disk, as well as Swap space is it's own disk.

For data (or apps), is it better to have 6 100GB virtual disks, or one big 600GB virtual disk?

It is for a file server. Technically I'm fine with making one big disk and creating shared folders on that disk and managing space through quotas, but wasn't sure if how Windows & VMWare handle virtual disks would be better. I need this server to be as reliable as possible as it's serving about 600 people.

Thank you.

[RParker]

I big honking, large, expansive, huge, humongous, gigantic VMDK file is the best way.. A bunch of little files just makes things more complicated, and more overhead.

[Rockapot]

I agree..., 1 x 600Gb is easier to manage.

Carl

[Rockapot]

Another thing..., what is the current block size ofyour VMFS data store...?..., you may have to create multiple small VMDK's if you have a 1mb block size.

If however you have a 4mb block size then you will be able to create a 600Gb virtual disk as the 4mb block size will support a VMDK up to 1024GB as per the following table..

Block size of 1mb = Max VMDK size of 256 GB

Block size of 2mb = Max VMDK size of 512 GB

Block size of 4mb = Max VMDK size of 1024 GB

Block size of 8mb = Max VMDK size of 2048 GB

Carl

[Texiwill · Accepted solution]

Hello,

I would say this depends on where the VMDKs are stored, if they are on multiple Data Stores then you could see benefits, but if they are all on the same data store then one large one is better.

Best regards,

Edward L. Haletky

VMware Communities User Moderator

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