Recovering a Deleted Virtual Machine with VVols

Virtual Volumes provide a great many benefits, some large, some small. Depending on the VM, recovering a deleted VM could be either of those.

With traditional VMFS, once you have selected “delete from disk” restoring that VM could have been a process. Either restoring from backup or hoping you had a snapshot of the VMFS on the array. Either way, you are probably going to incur data loss, as the last backup or snapshot is unlikely to be from the time right before the deletion.

Let me be VERY clear here. Regardless to the rest of this post, I am not saying once you move to VVols you do not need backup! You absolutely still do. VVols just give you a nice way to do an immediate recovery of the latest point-in-time without having to lose anything, assuming your array support it.

“Wait, did you say delete VM “AD” or VM “80”?”

“Um… definitely not AD that’s our active directory…”

Continue reading Recovering a Deleted Virtual Machine with VVols

Monitoring Automatic VMFS-6 UNMAP in ESXi

With VMFS-6, space reclamation is now an automatic, but asynchronous process. This is great because, well you don’t have to worry about running UNMAP anymore. But since it is asynchronous (and I mean like 12-24 hours later asynchronous) you lose the instant gratification of reclamation.

So you do find yourself wondering, did it actually reclaim anything?

Besides looking at the array and seeing space reclaimed, how can I see from ESXi if my space was reclaimed?

Continue reading Monitoring Automatic VMFS-6 UNMAP in ESXi

In-Guest UNMAP, EnableBlockDelete and VMFS-6

EnableBlockDelete is a setting in ESXi that has been around since ESXi 5.0 P3 I believe. It was initially introduced as a way to turn on and off the automatic VMFS UNMAP feature introduced in 5.0 and then eventually canned in 5.0 U1.

The description of the setting back in 5.0 was “Enable VMFS block delete”. The setting was then hidden and made defunct (it did nothing when you turned it off or on) until ESXi 6.0. The description then changed to “Enable VMFS block delete when UNMAP is issued from guest OS”. Continue reading In-Guest UNMAP, EnableBlockDelete and VMFS-6

In-Guest UNMAP and VMware Snapshots

Here we go with another in-guest UNMAP post. See other posts here:

https://www.codyhosterman.com/pure-storage-vmware-overview/flasharray-and-vmware-best-practices/space-reclamationunmap/

I was asked the following question the other day “does in-guest UNMAP work when snapshots exist?” To save you a long read: it does not work. But if you are interested in the details and my testing, read on.

My initial answer was “no” but I thought about some changes in VMFS-6 and reconsidered. If you refer to the vSphere 6.5 documentation you can see this change for VMFS 6:

“SEsparse is a default format for all delta disks on the VMFS6 datastores. On VMFS5, SEsparse is used for virtual disks of the size 2 TB and larger” Continue reading In-Guest UNMAP and VMware Snapshots