vMotion storage VM from 3Par to SimpliVity, thin provision only option?

[MrStarleaf]

Hello.

I just wonder when you use vMotion to move the storage for a VM from 3par to SimpliVity datastorage, I can only choose thin provision. But some VM disks are thick provision as they are used for database storage. 
But do I need to be worried, as thin provision is not recommended for database storage? Or do I have to do it in some other way to keep the VM disks thick provision?

[Shivam1]

Hi MrStarleaf,

Storage vMotion of VM's for a vmdk  does allow you to change the provision  to TPLZ  or TPEZ,this may hold good at data store (logical level) but on the disks (physical level) it will not lazy zero or eager zero any 8K blocks,hence remaining thin provision.You may want to check some documents on the refernce architecture of SImpliVity for Oracle DB or SQL DB.

[MrStarleaf]

Okay, but this is what I mean.  I can not choose anything else than Thin Provision in the "Select storage" under Select virtual disk format:. Normally you can choose TPLZ or TPEZ here as well. But if I move something to Simplivity Datastores, I can not. Maybe it's the way it should be but want to be sure before I move anything with a database stored on it.

[Shivam1]

Hi MrStarleaf,

Ideally you should see the options of choosing provisions  while doing storage vMotion at vmdk level,would you like to engage VMware support to check the process ?

[MrStarleaf]

If I create the VM (new one) on the SimpliVity storage I can choose Thin, TPLZ  or TPEZ when creating the disks. But if I do a Storage vMotion with an existing VM that is on the 3PAR to the SimpliVity datastore, I can only choose Thin, in the Storage vMotion process.

Maybe this is no problem, but I can't find any information about IF this is right or if something should be done.

For as I understand, and I have also check it. When you create a new TPLZ  or TPEZ disk on the SimpliVity storage, It will show up as a Thin if you look at the disk in VCSA late. BUT if you look in the vmdk file you will NOT have the “dd.thinProvisioned” attribute.

BUT if you move an existing VM from 3PAR to the SimpliVity Datastore with Storage vMotion, and you look in the vmdk you will see the “dd.thinProvisioned” attribute added after the move.

So do I need to be worry abut this for database disks that should be on TPEZ?
Or is this just how SimpliVity works?

I know that this thing that database disks should not be on Thin provisioned disks are related to old RAID/LUN technology. But I want to be sure I don't miss anything that need to be done.

[Randolfini]

Hi MrStarleaf,

I think VMware best practice is still TPEZ however I do not do that anymore. Unless you have an incredibly high transaction based database, you probably don't need it. Personally, on all flash SimpliVity node I wouldn't waste the space unless the SimpliVity node is dedicated only to that SQL server.

The SimpliVity all-flash will be so much faster than the 3PAR you won't have a problem with thin provision.

Previous to SimpliVity I used Tintri and did not thin provision there either. I've not had a problem on fast storage with thin provision in five or six years.

Just my $0.02.