Inconsistent Disk Usage - VM Crashing

[blaugusto]

Hi.

I installed Proxmox in a Dell Power Edge with Perc 6 and 3 RAID1 disks.
Disc 1- 240GB SSD disc for the Proxmox and VM
Disc 2- 1 1TB disc for data files
Disc 3- 1 2TB disc for backup files

Recently my VM crashes due to 100% usage of disc 3. 15 days ago I make a snapshot in this disk and, after deleting this snapshot, I can start the VM again.
Doing a cleanup and I noted some things.

Inside the VM it shows 450GB free space.
At the sumary of the VM it shows 99.42% usage (1.95 TB of 1.97 TB)

Those files are a backup of the data of 44 computers (made by Goodsync every 2 hours) and I have a backup of those backup.

So, theres some thing that I can do to solve this?

And theres something that I can do to not crash the VM again in case of full usage of the disk?

Kindly,
Bleno Rodrigues

 

[quanto11]

you should never set the storage of a VM higher or equal to that of the storage, always leave at least 10% free. In addition, your VM does not have “Discard On”, so that deleted data is not reported to the host, so that your storage is now displayed as full, although 1/4 of the storage is free in the VM.

1. shut down the VM, activate Discard On everywhere, delete all snapshots, start up the VM
2. defrag E: /L (for trimming)
3. now you have to fill the storage in the VM and delete it again, after that you execute the trimming again
4. defrag E: /L
5. during the trimming, storage is released on the host site

If you use ReFS, you have to enable SSD Emulation!

(this method is only working on ZFS, Ceph und LVM-thin)

 

[blaugusto]

Thanks for the advice.
Whats is for those 10% free space ? To extend in case of emergency?

And what if I remove the disk an re create with the right size.
Can I do this without restart the server?

 

[quanto11]

Thanks for the advice.
Whats is for those 10% free space ? To extend in case of emergency?

And what if I remove the disk an re create with the right size.
Can I do this without restart the server?

10% is spare, you should never overprovisioning storage space, which could result into data loss.

I think you are able to unmount while running the Server. You need to take the Volume offline via Windows, detach via Proxmox and recreate it with the needed settings, like discard on. Not 100% sure