VMware Horizon Community
PaulMurphyCO
Enthusiast
Enthusiast

Hard drive expands far larger than snapshot on parent VM after committing snapshot

Environment:

VMware Horizon 7.5

vSphere 6.7

Created a parent VM - disk usage size about 27 GB when done.

VM Hardware:  Hard disk 1 is 75 GB, thin provisioned, sitting on a VMFS 6 datastore.

Take snapshot 1 for use with linked-clones - disk usage size in the vSphere Web Client shows about 27 GB.

Take a second snapshot 2 with some updates and applications - disk usage size snapshot size is about 1.5 GB.

If I delete/commit snapshot 1, the storage usage goes up to almost the entire hard drive size - 74.82 GB.

I can do the sdelete/shrink disk to reclaim the disk space, but why would committing a snapshot that is no where near the size of hard drive cause the hard drive to expand to its full size?

Thanks for any help.

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a_p_
Leadership
Leadership

If what you explain is really the case, thenI'd consider this a huge bug, and you should open a support case with VMware.

The maximum growth of a thin provisioned virtual disk when deleting a snapshot should not exceed the snapshot's size.

How did you verify the virtual disk sizes?

The most reliable way to do this is to run ls -lisa from the command line. This command will show the provisioned size in bytes, as well as the used disk space in kB (second column).


André

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PaulMurphyCO
Enthusiast
Enthusiast

Hello Andre,

To verify, I browsed the files on the datastore via the vSphere Web console.  I also SSH'd into the host, navigated to the vm on the datastore, and ran:

ls -lh *.vmdk

and then to verify actual usage,

du -h *.vmdk

Thank you,

Paul Murphy

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