[SOLVED] Proxmox Backup only creating small incremental files after full backup deletion

[trinette.valle]

I installed Proxmox Backup Server and configured it as backup storage in my Proxmox cluster. I created a backup of my Windows VM but accidentally deleted the full backup. Now every new backup job only produces very small files, and I was expecting full backups.

Here is the VM configuration:

agent: 1
bios: ovmf
boot: order=scsi0
cores: 4
memory: 4160
name: WIN10-APP-SERVER
scsi0: local-zfs:vm-100-disk-0,backup=0,cache=writeback,discard=on,size=550G
scsihw: virtio-scsi-pci

And here is the storage configuration:

dir: local
path /var/lib/vz
content backup,vztmpl,iso

zfspool: local-zfs
pool rpool/data
content rootdir,images

dir: STORAGE1
path /mnt/pve/STORAGE1
content snippets,backup,vztmpl,images,rootdir,iso

What is strange is that the VM actually uses about 80 GB, but the backup file size is very small. How can I force Proxmox to make a proper full backup again?

 

[fcaiati]

The reason your backup is so small is because the VM disk is excluded from the backup. In your VM config the line

scsi0: local-zfs:vm-100-disk-0,backup=0,cache=writeback,discard=on,size=550G

contains the option backup=0. This explicitly tells Proxmox not to include that disk in any backup.
To fix this, remove the backup=0 option (either through the GUI or by running):

qm set 100 –scsi0 local-zfs:vm-100-disk-0,cache=writeback,discard=on,size=550G

Once you do that, the next backup will be a full backup. If you are using Proxmox Backup Server, it will always create full backups, but it deduplicates data chunks so repeated backups only consume minimal additional space.

 

[Neobin]

I installed Proxmox Backup Server and configured it as backup storage in my Proxmox cluster.

And here is the storage configuration:

dir: local
path /var/lib/vz
content backup,vztmpl,iso

zfspool: local-zfs
pool rpool/data
content rootdir,images

dir: STORAGE1
path /mnt/pve/STORAGE1
content snippets,backup,vztmpl,images,rootdir,iso

Sidenote:
There is no PBS configured in your storage configuration...

[0] https://pve.proxmox.com/pve-docs/chapter-pvesm.html#storage_pbs