Mixed size hard drives?

[Kruppa]

Hi,

I'm trying to confirm something about hard disks before I proceed. I recently obtained a few servers I visualized with ESXi and opted for direct attached storage.  I soon realized I wanted to do a lot more than I intended with these servers and will be purchasing additional hard disks to attach to these servers so I can create more virtual machines.  My servers currently have 2 x 300 GB hard disks each and this is really not enough.

I want to do something drastic like add a 2 TB disk to each server.  I just cannot seem to find any indication if this is ok or if it will create problems.  For example, is there some kind of rule where all disk drives must be the same size?  Will I be able to add these disks and create datastores from them or use them to extend the current datastores I have?

Thanks,

Mike

[jrmunday]

Hi Mike,

What server hardware are you using? Do you have an array controller card? Is this for PROD or just a test lab?

If you're planning on adding a single 2TB disk, you will be limited by the IOPS of a single spindle and have no redundancy. Depending on your requirements (and budget) it would be better to buy an array controller and increase the number of spindles in a RAID set (as per your requirements) both for performance and redundancy.

You can create a single datastore using extents, see KB link below;

VMware KB: Creating and managing extents on ESX/ESXi

Cheers,

Jon

Message was edited by: Jon Munday - KB link added

[Kruppa]

Hi Jon, thanks for your answer.

I'm using HP Proliant DL580G7 servers.  I do have an array controller but because this is a test environment only with a limited budget (our CFO hit the roof when he saw the cost of VM licensing) we don't have redundancy. Initially both 300 GB disks in each were set up as mirrored but removed to double the disk space.

Thanks,

Mike

[taylorb]

Those DL580's have 8 2.5" drive slots.  Biggest is 1.2TB SATA, I think.   You can use any configuration you want with the remaining drive slots.   You'll just create a new Array (have to boot into Array Config Utility or Smart Start) and then Vmware will see the disk and you can make another datastore.

You should keep all the drives the same size in an individual array, but if you are making a new seperate array, only those new ones need to match.