Why Virtual Machine Checkpoints and Snapshots can be Dangerous

[@ianjharris]

Really smart observation. Thank you for sharing this information.

[@techpub]

Thanks for watching!

[@dharmaboy75]

Thanks for this Robert. my big question is do you delete checkpoints with the vm off or can you do it while its up and running ie in a production environment?

[@techpub]

Yes you can. I've never had an issue while running.

[@ianjharris]

@@techpub Well it has to merge right? It doesn't quickly delete them anyways?

[@karamdhafer4895]

Do you mean we have to delete checkpoint after any new upgrade or update in my server to keep checkpoint in same file and reduce the size of checkpoint ? Can you make course just for hyper-v ?

[@techpub]

Yes, you just create them when you are about to do an update or install of some kind and delete them when done. Otherwise, your hard will fill up on the host. I do have lots of Hyper-V videos in a playlist. kzbin.info/aero/PLR7ujYtkzntYVkrbAP8kVcpkuu6DMBrax

[@MatSmithLondon]

What if you took a checkpoint, left it, then took another checkpoint. You need the latest one, but you want to delete the previous one? (I know the answer, but would be good to cover what goes on under the hood....)

[@techpub]

Unfortunately, that would compound the problem and make corruption even more likely.

[@pavelkraev7476]

Thanx Robert, but what I have to do in case if I don't want to merge checkpoints? I mean, if I installed some bad drivers or something like that and I want to undo changes to return to the original checkpoint (before I made changes)?

[@techpub]

You just right click on the checkpoint and choose to restore it and then it will go back to the previous.

[@RossKukes]

When using checkpoints in a domain environment, do domain users connect to the original vm or the checkpoint?

[@techpub]

They are one and the same but split into two files instead of one.

[@nathanwallace6204]

Great video, very well explained. Thanks!

[@techpub]

You are welcome! Thanks for watching.

[@cricken82]

I tried this on a server 2012 host that was running out of space on the partition with the hyper v clients. Unfortunately the merge ended up using the remainder of the hard drive capacity and all the hyper v clients paused I was able to compact and move a couple of smaller hyper v clients but the checkpoint is now gone from the hyper v gui. There are now additional avhdx being created Also I have been unable to export the server with the checkpoints, I get a generic failure error within the hyper v interface after a few hours. Any thoughts?

[@techpub]

Not sure about the avhdx file you lost other than backup and restore. I tend to just shut down the VM and copy the entire folder off and then setup the VM to use the avhdx when I have an issue like that.

[@robotikanet6279]

Good explanation... But! What if I don't want to merge together those two files, because something gone wrong during that update or driver installation or something. In that case I only would want to keep the original VM file. What is the process in this case?

[@techpub]

You just choose to delete the checkpoint and it merges the files automatically.

[@chaosmassive8627]

@@techpub correct me if I am wrong, but isnt supposed to _select_ the checkpoint instead?

[@addisutesfaye5585]

Ahh Professor! clear as day light!!

[@techpub]

Happy to help!

[@ramelpeduhan9342]

Hi Professor Robert. How to delete the checkpoint with label backup? and why its create automatically? thank you in advance...

[@techpub]

It does that during a backup but it should release when the backup job is over.

[@ramelpeduhan9342]

@@techpub Sir, how can I delete this checkpoint? I'm trying to delete as I do the other checkpoint but this one I got an error. "Cannot delete checkpoint subtree containing a recovery checkpoint."

[@Nobody423]

can checkpoints be created automatically i have a vm which is running on a check[point and im not happy about it, i noticed that when creating a vm in hyper checkpoints are checked by default and now a lsight change which says production checkpoint

[@techpub]

I haven't seen that happen except when a backup is run, but then it deletes it afterwards. Try right clicking and choosing delete. It will merge the files and hopefully not come back.

[@vangelis7479]

There is an option to turn on/off auto checkpoint on your VM. Shut it down, right click options, it's on the bottom tabs...

[@Naveenbabuborugadda]

Thank you. I will follow your tip

[@techpub]

Glad it helped. Please consider subbing.

[@achishka305]

well explained, thank you

[@techpub]

You are welcome!

[@zaid9166]

Thanks for informing

[@techpub]

Glad to help out.

[@brianjames2549]

Well that was brilliant. Simple explanation that should be easily available from Microsoft. It isn't!

[@techpub]

Glad it helped and thanks for watching.

[@fbgl7017]

I have a server withe 50 checkpoint and some one deleted all of them from the drive not from the hv manager. The server stoped working so they recovered the server from a backup , but there is a data gap of a period of time. my question is I have the checkpoint can I retrieve them back to there location and merge them withe the new server drive to fill the gap If not what is the best solution to my problem

[@techpub]

If you have them then yes you can do that. There is a powershell command to do it outside of HV. You'll have to look it up as I have only done it once.

[@fbgl7017]

@@techpub would I have a problem if two of my checkpoints overlapping and can that be implemented in the manager because i don’t have strong skills in powershell

[@vangelis7479]

Thank you!

[@techpub]

You're welcome!

[@MrOlivermarketing]

Mannn too late 😪... I'm learning win... server 2016/ 2019.. This happens.. 1.i created a windows server 2019 vm.. 2. Hyper v inside the w/s. 3. Create 4 machines.. 4. I created a checkpoint When I finished the class I just shutdown the vm's I never deleted the Checkpoint.( didn't know) 4. Next day I couldn't open the machine because an error.. Broken chain. Problem when attempting to open a virtual disk in a different chain.. The chain in the virtual hard disk is corrupted. There's a mismatch in the identifiers... Questio. So.if I delete the Checkpoint I'm going to be able to open the VM again or do I have to do something else... ??? Please help 🙏 😢....

[@techpub]

Good question. You should be able to delete the checkpoint but if you can't then you can go to the settings of the VM in Hyper-V manager and change where the hard drive points. When you have a checkpoint it points tot he checkpoint file. Change it to the original vhdx and start it up.

[@MrOlivermarketing]

@@techpub I would let you know.. thanks dude for your help.