Is it ok to "Run DRS" from within vCenter? What is the best way to balance a vCloud cluster?

[CHJamey]

Hello.  What is the best way to balance a vCloud cluster?  I have read that you are not supposed to do much outside of vCloud.  Thanks for your help.

[JasonBurrell]

I have never had a problem running DRS from vCenter on a vCloud cluster. It should be in automatic mode so if it is imbalanced a better idea might be up the level at which it migrates from 3 to 4 in the DRS settings.

-Jason

[SteveD03]

It is a requirement to enable DRS in vCenter for vCloud Director(vCD). Storage DRS is another thing. That would depend on the version vCD you have installed. The latest version of vCD does support SDRS.

[IamTHEvilONE]

Just agreeing here ... DRS should be full auto ... probably about a level 3/4 for recommendations.  Run DRS just provides level 4/5 recommendations, if you dont' apply them automagically.

vMotion/DRS is fully supported within the same resource Pool.

Storage vMotion is fine as well, but has a few more Caveats.

vCloud 1.5.x - You must stay within the same provider vDC datastore which is assigned to the Org for use.  you cannot SvMotion a Linked Clone chain.

vCloud 5.1.x - You can SvMotion a thin/thick disk within the same storage profile in vCenter.  Same logic applies to a Linked Clone chain, but requires vSphere 5.1 across the board to have it work.  For the purposes of Storage DRS, make sure to enable the feature "keep VM Disks together"

[rh5592]

just make sure not to "DISABLE DRS" I found out the hard way such action would result to!

[IamTHEvilONE]

Disabling DRS isn't so bad anymore, it just requires some service by a technician.  I've helped recover an environment where DRS was disabled in less than an hour.

[rh5592]

May i know how you did it? As I am reading Frank Denneman's article  that the Web client feature for saving the Resource Pool structure does not retain the moref id.. Thanks!

[IamTHEvilONE]

I'm a wizard ... not really, technical support has a tool to resolve this specific scenario.

[rh5592]

cool!

[SteveD03]

It is never OK to disable or not use DRS in a vCloud Director environment. Its only OK if your in a small environment of several vApps. Trust me, don't disable it, use it. I have seen clients not use it and the cluster was so imbalanced it caused severe resource contention and the clients couldn't work.

If you want to balance the cluster its best to calculate and use the percentage as a cluster setting in DRS and not the host tolerates setting. Read the VMware vSphere 5 Clustering Technical Deepdive by Duncan Epping and Frank Denneman. Its a great reference. 

[_morpheus_]

Under no circumstances should you EVER disable DRS in a vCloud environment