vSphere in a paradox

JDMurray

A theoretical chicken-and-the-egg question: Can vSphere operate properly in a VM on an ESX/i server that it itself is managing, or does this configuration create limitations in it operation?

I'd prefer not to have a separate box for only running vSphere, and having it live in a VM in a server that it is managing is my only other option. I don't see why not, but I thought I'd ask.

tiersten

You can do it if you want but it is a bit of a hassle since you may need to juggle it around. vMotion of the vSphere VM works. I've never tried storage vMotion of the vSphere VM though.

kalebksp

You can do that no problem. In fact I think it's VMware's recommendation to do so because you can leverage things like HA and vMotion.

kalebksp

This is for VI3 but much of it should apply to vSphere: Running VirtualCenter in a Virtual Machine

HeroPsycho

ESX servers cache down HA "rules of engagement from vCenter" and will continue to use them if it loses connection. So with that, yes, you can virtualize the vCenter instance on the servers it manages.

astorrs

Yes as others have said vCenter (not vSphere ) in a VM is recommended these days. There are some caveats if you want to use distributed virtual switches, but I'm guessing you don't have vSphere Enterprise Plus licenses for your hosts anyway.

tiersten

astorrs wrote: »

not vSphere

Oops. Maybe I should reread my notes...

pennystrader

I am currently running Vcenter as a virtual machine because it take 3gb (recommended but I give it 2gb and it is fast). VMware definitely suggest it can be virtualized for HA and FT purposes. I am studying about it now as I prepare for the VCP 4.0 upgrade this month so I don't have to take training. Anyways I am running it virtually and it works great and doesn't waste more hardware.

JDMurray

pennystrader wrote: »

Anyways I am running it virtually and it works great and doesn't waste more hardware.

Super! Thanks very much everybody.

Hyper-Me

Sortve related. You can run SCVMM in a hyper-v VM and manage the host on its on without a hitch.

I did this to lab SCVMM once.

JDMurray

Hyper-Me wrote: »

Sortve related. You can run SCVMM in a hyper-v VM and manage the host on its on without a hitch.

I did this to lab SCVMM once.

Good to know. I very well need to do this one day too. Thx.

blargoe

I've been running vCenter in a VM and have been mostly satisfied with some caveats. Just this weekend I was having intermittent problems with one of my hosts, the one that just happened to be running vCenter, and that was causing me not to have access to vCenter, so I had to log in to each host individually to chase it down.

VMotion and SVMotion work fine for a vCenter VM.

If you have everything configured perfectly you should be OK most of the time, but there will be a time or two that you need to connect to vCenter to resolve a problem, to find that you can't reach the vCenter server, because it is impacted by the problem.

If I had it to do over I probably would continue using it in a VM. I have read that vCenter can be run as a clustered service in MSCS, which might give you a little more resiliency. I haven't tried it.

NightShade03

We run our SAP servers in a VMware setup and the vCenter is installed in a virtual machine. Like others have stated all the engineers I talked to when building the project recommended doing it virtually.

astorrs

blargoe wrote: »

Just this weekend I was having intermittent problems with one of my hosts, the one that just happened to be running vCenter, and that was causing me not to have access to vCenter, so I had to log in to each host individually to chase it down.

Best practice says you should disable it for DRS and place it on a specific node. Set it for high priority on HA restart too. That way the only times it won't be on the specific host - is when you manually move it to another host to perform maintenance on the usual host (always have a 2nd server you move it to for this purpose) or if the host goes down, in which case HA should restart it for you on another host immediately (at which point you should manually move it to that 2nd "backup" host) - that way everyone just needs to look on those 2 hosts for it (if not on #1 then on #2).

Also if you have your vCenter database stored on a separate VM (common in larger environments) make sure you set the same settings for it - they should both be collocated on the same host since most of the communication between them can occur within the hosts memory and not need to hit the network.

JDMurray

blargoe wrote: »

If you have everything configured perfectly you should be OK most of the time, but there will be a time or two that you need to connect to vCenter to resolve a problem, to find that you can't reach the vCenter server, because it is impacted by the problem.

I'll have to keep that in mind. The only time I haven't been able to connect to a VM using vSphere Client is when the VM's files were damaged, didn't convert properly, or the guest OS itself was hosed. What type of problem might prevent vCenter from communicating with VM hosts?

NightShade03

JDMurray wrote: »

I'll have to keep that in mind. The only time I haven't been able to connect to a VM using vSphere Client is when the VM's files were damaged, didn't convert properly, or the guest OS itself was hosed. What type of problem might prevent vCenter from communicating with VM hosts?

We have 3 blades and the first two contain all sorts of vm machines (the VM hosts). On the third blade is a single VM which runs vCenter. If the third blade dies (from hardware failure) vCenter will lose touch will all hosts. Just an example of how we run.