vCenter on a VVOL?

[sraudonis]

Hello,

i'm currenty testing in my vSphere 7 environment VVOL's. I have installed the Virtual Storage Console 9.7.1 on a local datastore of my host.

But where to place the vCenter Server?

Here i got different informations about placing on a VVOL, someone told me that should be no problem, others tole me that isn't supported, or only not recommended.

Fact is, even if the vCenter Server isn't running, i can power on VM's on the ESXi Host directly. So for only powering on VM's the vCenter isn't needed.

Last weekend i updated my single controller NetApp to 9.7P8 and all was powered off.

First i tryed to power on the VSC, but when the VSC don't reach the vCenter it cames with the wizard to configure a vcenter connection.

When the VSC is running, it don't need the vCenter to power on VM's, but i can't start the VSC without a vCenter. If the vCenter is on a VVOL i got a chicken egg problem... In this case a vCenter can't be on a VVOL.

But my question now, is this correct? Why can't a already configured VSC start the services and connect later to a vCenter when is came available?

Kind regards

Stefan

[paul_stejskal]

That may be by design so VSC gets the feel of where everything is. ESX may not have the APIs to know what is where I'd guess.

I'd just recommend opening a case honestly, because that may be the best way to get the answer.

[sraudonis]

The VASA Provider has a internal database and cache the informations he got from the vCenter, must be, because i can shutdown, power off, reove the vCenter from inventory of the host, add it to the inventory and power on the vCenter again without problems, when the vCenter in on a VVOL and the VASA is still running.

The VASA is getting informations like profiles from the vCenter and perhaps a inventory. All other actions mut be done directly with the ESXi host.

I have a case open at NetApp and VMware regarding a other problem: https://communities.vmware.com/thread/644618

During this case i asked the supporter regarding the VSC boot behavior and he told me that the vCenter must be available for a fully function VASA provider. This is a normal behavior, because the VSC is a virutal appliance...

And i also talked to a VMware specialist from NetApp and he was wondering about this behavior too, in his view this behavior was in the past different.

In my view there is little design problem, why not booting the VASA with the last cached informations and wait for the vCenter connection.

O.k. this scenario will be happen very rarely, that all will be powered off, but if so it can be a large problem...

[sraudonis]

I made a few tests:

The vCenter is down - then reboot the VSC - the VSC runs into a wizard to enter new vCenter data - the VSC waits here for 4 minutes and then continue booting.

Now the vCenter is still down and the VSC is just rebootet and up again, but i can't start VM's on a VVOL datastore.

I powered on the vCenter, but even 20 minutes after the vCenter was available i still can't power on VM's on a VVOL.

So i made a 2nd reboot on the VSC and after this all is working again.

Some facts i figured out:

- The VSC/VASA caches infos from vCenter, it is possible that i can power on VM when the vCenter isn't available.

- But this cached infos getting lost during a reboot of the VSC.

- If the vCenter isn't available during boot of the VSC, the VSC don't connect to the vCenter and isn't trying it again after some time.

As a result i say: Don't put a vCenter on a VVOL, perhaps only when it is managed by a other vCenter Server...

And regarding my open cases: VMware has closed the case, because they can't find something in the logs and to escalate this i should bring my environment to versions that are listed on the VMware HCL.

Has someone looked to the HCL? The latest verson listed there is:

• ESXi 6.5 U3
• VASA Provider 7.1P1 (end of support since jan 2019)
• ONTAP 9.4 (end of support since jun 2019)

But someone from NetApp told me that NetApp is working on that... I hope that will not need much time, that i can reopen my VMware case...

Currently i will say: Don't use VVOL's!

And when using VVOL's, watch in the VMware HCL too, not only in the NetApp IMT. Because VMware don't help you when the Versions are not listed in their HCL.

[Oli71]

TL;DR

You are correct you don't mix mgmt VMs with vVols. You leave them on traditional storage.  NetApp is the only storage vendor using a VM for their VASA while all others integrate that logic to their controllers. Why? NetApp believes it is more scalable.  A while back, I noticed also the appliance is requiering vCenter to start all services.

I never implemented vVols in productions, too many drawbacks (not compatible with snapmirror) or missing.  It is supposed to be all solved now but still they aren't hight in VMware HCL for vVols.

Oli