Is it okay if each ESXi with the same datastore mounted is registered in a different vCenter?

[hoon0715]

Hi, all.

The title is the my question.

I'm currently using vCenter 7.0 and have two clusters underneath it.

One cluster has ESXi 6.5 hosts registered, and the other cluster has ESXi 7.0 hosts registered.

And, I'm going to upgrade vCenter to 8.0 in soon or later.

ESXi 7.0 is compatible with vCenter 8.0, but ESXi 6.5 is not.

So, I decide not to upgrade vCenter to 8.0, but to create a new vCenter 8.0. 

After that, move the ESX 7.0 hosts to the new vCenter 8.0.

Finally, ESXi 6.5 will be located in vCenter 7.0 (old), and ESXi 7.0 will be located in vCenter 8.0 (new).

In this case, each vCenters will see the same Datastore, so what could be occure the problems??

Thanks in advance!

[Nick Merlevede]

No idea if it is possible. But don't think it's a good option.

The 2 vCenters don't know each other and it give a risk when it comes to handeling the vm's and configuration 

[RedVillager]

Think about cases where the two vCenters may both want to use the same free space on a datastore - is there any overprovisioning that they could both step into the same space?  Is this one datastore or multiple?  Is DRS enabled?

If one datastore then over provisioning is probably your only nemesis, if multiple then datastore vmotions could also get in the way.

[Alfista_PS]

Hi,

yes its possible. Each cluster has its own vCenter for managing and this should have the licenses for their hosts.

You can do it so that you will have one vCenter 8 with two clusters but I'm now unsure if the version 8 will accept the 6.5 hosts.

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Alfista

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If may my answer has helped you or resolved your problem or question mark it as RESOLVED.
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[Alfista_PS]

Hi,

yes its possible. Each cluster has its own vCenter for managing and this should have the licenses for their hosts.

You can do it so that you will have one vCenter 8 with two clusters but I'm now unsure if the version 8 will accept the 6.5 hosts.

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Alfista

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If may my answer has helped you or resolved your problem or question mark it as RESOLVED.
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[Neil Burfoot]

My understanding has always been that a Datacentre is the security and cluster boundary, so if you share a datastore across Datacentres, as you would have to with two vCenters then you risk data corruption as you wouldn't have control of the data locking.

[Alfista_PS]

DC is only like a place and you can have there many clusters. The clusters are build as that they use unique and in the cluster the same HW for easier managing. So you can have one cluster with with older HW and another with newer, or you can have clusters depends on workflows you use etc.. there is many possibilities. But some functionalities like migrating VM's between clusters or DC are done manually over special functions but inside the cluster you can use DRS, or standard vMotion. And when you have one VM registered in one cluster then teh VM has a lock file and it will warn you that the VM is used in another place. So you cant corrupt the files.

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Alfista

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If may my answer has helped you or resolved your problem or question mark it as RESOLVED.
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[Duncan Epping]

on the topic of data corruption, VMFS has a very advanced locking mechanism, no way two hosts can actively run the same VM and write to disk at the same time. The locking mechanism prevents this from happening.

[Duncan Epping]

yes that is fine. we typically recommend customers to not do this because it just complicates operations, but there's absolutely no technical reason why you couldn't do this. The only thing to keep in mind is that if you ever upgrade VMFS from one version to another is that both clusters support the same version of VMFS.

[na1231]

As for as I understand it,

Best Option is First Upgrade your ESXi hosts from 6.5 to ESXi 7.x which is compatible with vCenter 8.x in this case you don't have to have two Separate vCenter servers.

If  ESXi Upgrade from 6.5 is not possible for you then you can have another vCenter (New) with 8.x, remove ESXi hosts 7.x from Old vCenter and add it to New vCenter 8.x

Hope this will help you.

Thanks