IO Error/VM Yellow Triangle - SSD suddenly becomes full

[DigiDoc]

Hello all,
I woke up this morning and found out 2 VMs are down. Both are installed on SSD 250GB drive allocated 80gb and 32gb respectively. Today I found out the hdd is completely full and VM is not loading. I moved one VM to the LVM-Thin. Now I am able to run 6.4gb space available (sdd1). How can I troubleshoot this. I found similar problem in the past years but I was not able to fix my issue. Here is my df -h output:

 

[leesteken]

Looks like /mnt/samssd is the full drive? Try find /mnt/samssd/ -type f -exec du -Sh {} + | sort -rh | head -n 20 to find the largest couple of files.

 

[DigiDoc]

Looks like /mnt/samssd is the full drive? Try find /mnt/samssd/ -type f -exec du -Sh {} + | sort -rh | head -n 20 to find the largest couple of files.

Thank you for your response. Here is my output: the top 2 are not known to me. The third result belongs to vm 101 to lvm-thin to spare some space.

 

[leesteken]

There appear to be virtual disks for at least 5 VMs on that drive. The first virtual disk (of type qcow2) of VM 102 takes 205GB of space.
If you did not enable the Discard option and don't run discard or trim inside the VM (depends on the operating system) then deleted files also take space.

EDIT: If you do not know those VMs, then I suggest you ask the person who created them. Or if you deleted the VMs, maybe the virtual disk was not deleted for some reason and you can delete the files. Or this drive was used in some other Proxmox system before?

 

[DigiDoc]

Those VMs are OPNsense and ubuntu-based VMs. I do not find those in the GUI. Appreciate your help.

*update: I found the Discard option in HDD configuration. Does it matter whether I pass through the HDD or not?