Changing Max File/Block Size

[InflxxEC]

When I formatted my storage I accepted the default maximium file size and block size. I wasn't aware this would limit the size of my datastores (i thought it was just the max size of a file). Is there anyway to change this on the fly or do i have to svmotion everything off and then delete and re-add the storage?

Thanks.

[golddiggie · Accepted solution]

The LUN/Datastore would be limited to 2TB-512k in size (through ESX/ESXi 4.1 u1/VMFS 3.x). Depending on the block size you went with, VMDK files will be limited to a max size. Such as 256GB with a 1MB block size. If you need larger VMDK files, then you'll need to storage vMotion the VM's off of the LUN/Datastore, reformat/recreate the LUN/Datastore, then move them back onto it.

This is part of proper planning of how you set up the LUNs... If you need to have 500GB VMDK files, then don't use the 1MB block size. By the same token, don't use 8MB block size if you're going to have <256GB VMDK files.

[Troy_Clavell]

...do i have to svmotion everything off and then delete and re-add the storage

Yes, as stated, this is really your only opiton.  With that said, it may just be worth formatting with an 8MB block size.

[MauroBonder]

To change block size of VMFS you need reformat volume.

Check Too Block Size and Limitations of VMFS

Please, don't forget the awarding points for "helpful" and/or "correct" answers. 

Mauro Bonder - Moderator