Centralized vCenter vs Multiple vCenters

[BostonTechGuy]

Hello,

Proposing a discussion on single vCenters vs Multiple vCenters.  It seems to to me that its a preference aka "religious" discussion beyond the major technical requirement.  The only technical requirements that I can find for multiple production sites to have their own vCenters are:

• SRM
• VDI (horizon or otherwise)

Yes there is a limits issue that vCenter can only handle X amount of VMs and Y amount of Hosts.  Assume for this discuss that is an issue. Should an environment be of that size, multiple vCenters is a given and not needed for this discussion.

I started another thread here Re: Multi-Site vSphere Environments - Best Way to use VCENTER

Basically reviewing Multi-Production sites with their own vCenter vs centralized vCenter.  However I really want to hear the plus and minus of why people choose one option over the other.  Give any and all reasons.

What did you do?  What is your opinion on which direction and why?

Thanks,

Boston Tech Guy

[Vikas Shitole]

This flowchart on various SSO deployment type is really impressive : http://www.joshodgers.com/wp-content/uploads/2013/06/SSO-flowchart-V1.0.jpg

Just thought it is worth to share.

Refer: vCenter Single Sign On aka SSO, what do I recommend?    This post refers to most relevant data on SSO deployment types.

[admin]

Load and availability/security are also factors to consider. Take View or vCloud for example, all the VM operations are putting a HUGE load on vCenter which can cause the service to collapse way before reaching the theoretical maximums.

Also backup software tends to log in for each job and start a propertyCollector iteration which can also put enormous pressure on VC from a performance point of view.

Separation for workload clusters and not having the vCenter managing itself might also be needed in some environments.

[BostonTechGuy]

All very good points.  Thank you.

One of the more interesting challenges has been on workflow and vCenter.  What is the business doing/requiring.  I have worked in environments that are completely centralized to extremely decentralized. In all cases there was plenty of discussion getting more vCenter Servers or cutting down on the number of vCenter Servers.

Is it possible to have a sites vCenter do VDI if the overhead for vSphere is very low? I know its still recommended for VDI to have its own vCenter but with if the vCenter was really doing nothing for the vSphere environment?

Thanks,

BostonTechGuy

[admin]

It is possible, but usually you want to have DRS enabled, still do some vMotions etc. these things can quickly add up quite a bit.

Have a look here how DRS alone can get vCenter under enormous pressure: http://fbuechsel.eu/2014/06/15/used-features-impacting-vcenter-server-minimum-requirements/

And now imagine you want to add all those create, poweron and delete tasks on top of it. Furthermore what happens if something goes wrong with the workload infrastructure, your management system will reside on that very same infrastructure. It might not sound much right now, but noticing that you can't do certain tasks in the amount of time you would need to could really hurt your SLAs.