VM Disk Greater Than 2TB Issue | Nutanix Community
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We’re running 2 clusters which are pretty much configured the same running ESxi 7.02 AOS 5.20.4 LTS both running on nutanix hardware.  One cluster is totally fine no issues but the other you cannot create a virtual disk greater than 2Tb! The issue only came to light when we had to move a VM off to another non-nutanix host for a few days then when we went to vmotion it back it errored complaining about the disk being greater than 2Tb, it is its nearly 6Tb as its a fortinet analyzer. 

I’m pretty sure when the VM was sat on the nutanix cluster its disk was greater than 2Tb and it was thin provisioned with a capacity of 7Tb when it was created!  So you can’t move anything to any of the datastores that are greater than 2Tb and you also can’t create a new disk greater than 2TB.  Also if you take a look at the datastores details it says maximum VM disk size 2TB, on the other clusters datastore it says 62Tb. 

It's getting to be a bit of a pain as the fortinet analyzer is sitting on a box we want to decom so we’d like to move it back to the cluster where it came from, it can’t go to the other cluster for resilience reasons as that cluster hosts our other analyzer, and being 7Tb I don’t really want to shift it up in to Azure either! I had a ticket open with VMWare, and they said it was a storage issue and blamed the storage vendor ie Nutanix, and they were quite frankly useless!

 

 

Hello @Khoskin 

First, Nutanix supports 62TB disk size for esxi 5.5 and later.

Second, you said you moved VM to Non-Nutanix host, what is the datastore and VM hardware version when it migrated there? I guess if the datastore is VMFS3 or the VM hardware v. Is 9 or earlier, then here is the program.

Third, when migrate VMs to Nutanix I recommend to use Nutanix Move migration tool.

Those kb will be helpful

https://kb.vmware.com/s/article/2058287

https://4sysops.com/archives/how-to-hot-extend-vmdk-disk-over-2-tb-with-vsphere-7-0/

 

moving the VM to the non-nutanix host isn’t the issue that’s just how we found out about the issue.  The VM was vmotioned to the non-nutanix host as all our hosts both nutanix and non-nutanix are managed by the same vCenter  The issue, as you can see from the screen shots, is on the second cluster you CANNOT create or move to that cluster a VM with a greater than 2Tb disk!  Both clusters datastores have been created the same, NFS3 and both clusters are the same AOS and ESXi version.

moving the VM to the non-nutanix host isn’t the issue that’s just how we found out about the issue.  The VM was vmotioned to the non-nutanix host as all our hosts both nutanix and non-nutanix are managed by the same vCenter  The issue, as you can see from the screen shots, is on the second cluster you CANNOT create or move to that cluster a VM with a greater than 2Tb disk!  Both clusters datastores have been created the same, NFS3 and both clusters are the same AOS and ESXi version.

@Khoskin could you please try to login esxi host UI and create a VM with 62TB disk and see if it works or not?

Looking forward to your feedback.

interestingly that works!  logging in to a nutanix hosts UI on that cluster allows a greater than 2TB disk to be created.

 

Going back to vCenter you can see the disk but attempting to create another fails as you can see by the red ! 

 

Hello @Khoskin 

It seems as a bug in vCenter. Nothing related to Nutanix. I hope it is solved.

kind of hoping it was a Nutanix issue as VMWare support is awful!!! Hoping to get rid of VMWare in the next year or so when we do a infrastructure refresh and go to straight AHV.

Now I need to get the 6Tb VM moved over to the cluster now some other way that isn’t VMotion via vCenter!

Hello @Khoskin 

1- You can use Nutanix Move to migrate VMs from:

ESXi to ESXi (AOS)

ESXi to AHV

AHV to AHV

and more

For further details: https://portal.nutanix.com/page/documents/details?targetId=Nutanix-Move-v4_6:top-overview-c.html

2- Regarding Migration to AHV, the In-place hypervisor conversion feature provides you with an option to convert your existing ESXi cluster to an AHV cluster.All the VMs that are running in the ESXi cluster are converted so that they can run on the AHV cluster. The VM conversion is independent of the host that the VM is running on. The conversion process occurs in such a way that the VM down time is minimised. You can also convert the cluster back to ESXi. This conversion from AHV to ESXi is a file system restore of the host. Hence the cluster will be similar to what it was before the conversion. For Further details: https://portal.nutanix.com/page/documents/details?targetId=Web-Console-Guide-Prism-v6_5:man-cluster-conversion-c.html

might take a look at the Nutanix move tool.  Typically the host that the fortinet analyser is on actually failed this morning! LOL  We’ve managed to get it up but might look to try and move the VM across to the cluster it came from, we might be able to do it using our backup solution (rubrik) and just do a restore back to the nutanix cluster

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