Can't take snapshots of VM

[Gilera]

I recently set up a server with Proxmox running a Windows VM with Blue Iris CCTV software. Proxmox is installed on a 64GB SSD and my VM is on a separate 500GB SSD. I am new to Proxmox and soon found that I could not take Snapshots - "The current guest configuration does not support taking new snapshots". After doing some reading, I realized that this was likely due to me having set up the 500GB SSD as LVM storage type instead of LVM-thin. I set up another drive and took a backup of the VM (my 64GB SSD was not big enough). I wiped the 500GB SSD and then set it up as LVM-thin and restored the VM. All went well but I still cannot take Snapshots with the same configuration message. I then read that TPM state can affect this and also that the disks have to be QCOW2. I tried removing the TPM state disk but this didn't fix the issue.

Can anyone give me advice on where to go from here? When I look at the storage in Datacenter it shows 3 partitions on the drive all as RAW. I assume these are the EFI, TPM and VM.

 

[Impact]

Please share qm config VMIDHERE --current and cat /etc/pve/storage.cfg.

 

[Gilera]

agent: 1
bios: ovmf
boot: order=ide2;scsi0
cores: 4
cpu: host
efidisk0: SSD500GB:vm-100-disk-0,efitype=4m,pre-enrolled-keys=1,size=4M
ide0: local:iso/virtio-win-0.1.271.iso,media=cdrom,size=709474K
ide2: local:iso/Win10_22H2_EnglishInternational_x64.iso,media=cdrom,size=5969910K
machine: pc-q35-9.2+pve1
memory: 8192
meta: creation-qemu=9.2.0,ctime=1749185906
name: WinVM
net0: virtio=BC:24:11:7D:BC:D3,bridge=vmbr0,firewall=1
numa: 0
onboot: 1
ostype: win11
scsi0: SSD500GB:vm-100-disk-1,iothread=1,size=128G
scsihw: virtio-scsi-single
smbios1: uuid=12dbb904-98a2-443b-92f0-74911eab01db
sockets: 1
tpmstate0: SSD500GB:vm-100-disk-3,size=4M,version=v2.0
unused0: SSD500GB:vm-100-disk-2
virtio2: /dev/disk/by-id/ata-ST4000VX000-2AG166_WDH1614P,backup=0,size=3907018584K
virtio3: /dev/disk/by-id/ata-ST4000VX000-2AG166_WDH1B033,backup=0,size=3907018584K
vmgenid: b95116dc-4e21-44eb-9bc9-1701460300b1

 

[Gilera]

dir: local
path /var/lib/vz
content vztmpl,iso,backup
lvmthin: local-lvm
thinpool data
vgname pve
content images,rootdir
dir: Backup
path /mnt/pve/Backup
content images,vztmpl,backup,snippets,iso,rootdir
is_mountpoint 1
nodes Proxmox-Dell5820
lvmthin: SSD500GB
thinpool SSD500GB
vgname SSD500GB
content rootdir,images

 

[gfngfn256]

virtio2: /dev/disk/by-id/ata-ST4000VX000-2AG166_WDH1614P,backup=0,size=3907018584K
virtio3: /dev/disk/by-id/ata-ST4000VX000-2AG166_WDH1B033,backup=0,size=3907018584K

AFAIK those 2 passed through disks won't allow VM snapshots - even though backup=0 has been selected. There has been some discussion on this forum as to why this is the case - & even a Proxmox Bugzilla filling for this.

I then read that TPM state can affect this and also that the disks have to be QCOW2.

tpmstate disks themselves can only be in raw format & as such if they are on a non-snapshot capable storage, they will stop VMs of being snapshot-capable. However in your case - it appears the tpmstate0 in on LVM-thin which should allow snapshotting inherently.

For a better understanding - see here.

 

[Gilera]

Well at least that explains it, thanks. I guess i'll just have to stick to doing backups instead.