30-50 VM's per VMFS lun?

[mlubinski]

Hello,

Did anyone succeed with placing 30-50 VM's (single VMDK) on VMFS luns (without VAAI)? If yes, could you please share what kind (how much IO) of IO load you are doing to these LUNs?

I also heard that with VAAI you can successfuly deploy over 100VM's per vmfs datastore without scsi reservations issue.

Right now we use NFS which doesn't have that issue, but we are considering using in some moment iSCSI, but because of pretty large amount of VM's that would be placed on one LUN (preferably 50+) it can't cause serious issues to lower our management of possible problems...

Thank you in advance for your thoughts and advices on that question.

Marek

[AndreTheGiant]

You must make a check of your workload requirement to see which kind of VM you have and how much need write and/or read performance.

Usually you can have 3-5 VMs on each spindle... but this also depends by the type of disks.

Andre 

[mlubinski]

let's say 24 disks in RAID 10 (all disks SATA). I don't care about IO/s right now, just number of VM's to avoid issues with SCSI reservations. If 50 VM/lun would be "ok" then I may consider that kind of storage (iscsi without vaai), otherwise I would run into management problems

[AndreTheGiant · Accepted solution]

SCSI reservation has been improved in 4.1, also without VAAI.

But I've never tried 50 VMs on a single LUNs (I've only try around 30 VMs without big issues).

Andre

[mlubinski]

Andre,

Thanks for your reply. I will try that out, maybe that will be the way to go