Backing up a disk excluded from regular backups


New Member
Nov 12, 2023
First, I'm a home user and have no Proxmox Backup Server.

I have a very large disk containing the backups of my Desktop PCs using Acronis True Image. This disk has 8 TB. I excluded it from regular backups because the seem not to be incremental and that would produce a huge file on every backup. I just have not enough storage. Most files on this disk change seldom.

No, I wonder how I could backup this disk? It would be nice to have the backups in the GUI.

I figured out, that I can create a snapshot of that virtual disk in PVE. But I still cannot mount that snapshot. Inside the VM, the disk belongs to a LVM but just contains a single LV which is not shared with another PV.
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you need to switch to proxmox backup server to get only changed data backup.
PBS never rewrite/store same data already backup.
original vzdump backup is always a full recopy.
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Or backup the contents of that excluded disk with the backup software of your choice from within the GuestOS.
PBS is not affordable, I run a home server and don't want to pay for another remote server with so much storage capacity.

Isn't it possible to mount the gust disk from PVE host? I already know how to take a snapshot of this disk, it should be possible to mount that snapshot and then back it up. This could be done read-only so that nothing can break.
You can install PBS in the same host you are running PVE and use the same disk used as destination of vzdump backup files as a PBS datastore. It will cost you exactly zero (time aside) and you'll be able to do all your backups from the GUI in an efficient way.

There are other options like installing PBS as a VM or in a LXC, but as I don't know what kind of storage you use as destination it might be harder to get the setup right.
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Haha, thanks! This was not clear that this is possible as well, Will try it out now! I could then use USB disks as well, very cool!
When using a 100G WebDAV share for sync, how can I exclude single disks from backup? Just want to save OS images here.
I have a veryyy large disk (multiple TB) containing Backups of my desktop PCs. This disk is backed up in PBS. I want to add a remote backup folder for WebDAV. This folder is limited to 100 GB. Most valueable data should be transferred here. The question is, how to
  • exclude very large disks or paths in the file system of the guest VM
  • how to mount / unmount the WebDAV volume automatically before the sync job.
How are you doing the backups?

If you are backing up the whole VM from PVE you cant exclude paths inside the VM, you can only exclude disk(s) (edit VM disk you want to exclude and untick backup). A webdav (or any other kind of mount) in the VM guest OS will never be included in the backup of the VM.
Yes, I know that checkbox to exclude. But I don't want to exclude them all the time, I just want them to be excluded from remote sync (redundancy of most important data). Can't I exclude disks/paths from being synced?


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