I have a business case to setup ESXi 4.1 3-host cluster to host about 20 business critical servers and I am wondering what is the best setup/design route for vCenter Server; physical or virtual?
I reviewed the available resources, but a lot of that is dated and I am wondering how all that is applicable when using Network Distributed Switch in virtual environment?
Could someone please point me some latest documentation or share hands-on experience when dealing with vCenter Server as VM when it comes to system recovery, patching, maintenance etc.
I appreciate any help.
I always deploy vCenter as a VM.
To your question about system recovery, like most other things, vCenter is required to configure features such as HA and vDS, but then the operational state is passed off to the host. In situations where vCenter is offline (HA event, patching, etc.), the hosts continue operating unaffected.
I have heard the argument for a physical deployment in the case of many (more than 3) hosts due to the challenge of finding the host vCenter is registered to in the event of a complete shutdown. Even in that scenario, you could always use host affinity rules to keep vCenter in one place and not allow it to be automatically moved by DRS.
You make the comment that a lot of the docs and resources are dated, and that is what I would say about the practice of having vCenter as a physical deployment, it's dated. I have yet to hear any generally accepted reasons to deploy vCenter physically as opposed to virtually. Ultimately, the only reason I ever see left standing is "because that is what I am confortable with". That is a legitimate reason, just devoid of anything technical.
For reference purposes, the VMware publication "ESX and vCenter Server Installation Guide" (http://www.vmware.com/pdf/vsphere4/r41/vsp_41_esx_vc_installation_guide.pdf) on page 16 in the section "vCenter Server and the vSphere Client Hardware Requirements" states: "The vCenter Server system is a physical machine or virtual machine with access to a supported database."
The guide doesn't state which it should be, just what it can be. In addition to that, what I can tell you is that I recently attended VMware vSphere: Datacenter Design Workshop at VMware Partner Exchange 2011 in February. It was revealed in that course that it is now considered a VMware best practice to deploy vCenter as a VM. One of the explanations given for VMware adopting this as a best practice is because all of the design submissions for the VCDX accredidation included vCenter as a VM. So if all of the most advanced VMware experts say it's a good way to go about it, I'm not going to argue (aparently, neither is VMware).
IMO, it somewhat undermines the message of virtualization by saying "Virtualization is ready to host your business critical services . . . oh wait, don't virtualize vCenter, it's too critical." ??? Enough of that rant. What I am hoping for is a vCenter virtual appliance. If/when that happens, it will hopefully lay to rest the great "vCenter: Physical or Virtual?" debate.
Hope I didn't bore you too much with my lengthy response and that it helps you in your design decisions.