Does PBS allow backup while VMs are up?

[Ratio]

Hello,

I would like to know if PBS can perform backups without manually stopping the VMs beforehand and without any bugs in the process.

We currently have an NFS storage configuration with ".raw" files and our backup solution is PVE.

I know that with PVE we can't bakup while up with our current configuration (otherwise it completly breaks the VM), that's a thing we want to improve and maybe PBS is the solution, but first I want to make it sure.

Thank you.

 

[dietmar]

I know that with PVE we can't bakup while up with our current configuration (otherwise it completly breaks the VM),

Sorry, but that sounds strange. What problem do you have exactly?

 

[Ratio]

Sorry, but that sounds strange. What problem do you have exactly?

Hello,

With our current configuration (nfs storage and vm with raw file) the snapshots with PVE can't be done while the vm is up otherwise the vm just become corrupted (we already faced the issue before).

We found a webpage that support our current issue: https://pve.proxmox.com/wiki/Storage
NFS is classified "no" for snapshots.

If we were in qcow2 it would work fine but not in our case :/

That's why I wanted to know if PBS can do snapshots while the vms are up without corrupting them.

 

[dietmar]

With our current configuration (nfs storage and vm with raw file) the snapshots with PVE can't be done while the vm is up otherwise the vm just become corrupted (we already faced the issue before).

This is not true. Proxmox backup use a special qemu feature to make snapshots (copy before write), and this is storage independent, i.e. it also works on NFS/raw.

 

[Ratio]

In the past, with PVE release 5.3 when backuping VM with raw files on NFS storage, the VM crashed (We also found on your wiki that snapshots with nfs and raw file don't work if you don't have qcow2 file system)




in this link: https://pve.proxmox.com/wiki/Storage

And just to be sure I'm talking about Proxmox Virtual Environnement (PVE).

Maybe I'm wrong but the fact is we already crashed a vm in the past by doing snapshots while VM is up with PVE.
That's weird

 

[dietmar]

In the past, with PVE release 5.3 when backuping VM with raw files on NFS storage, the VM crashed

Please test again with the current version. It should work without problems.

 

[fiona]

Hi,
and if you still have issues with backup with current versions, please try reducing the amount of workers and/or enable backup fleecing in the Advanced settings when editing the backup job.

 

[Ratio]

Hi,
Thank you for your feedback!

Actually I think we will switch to PBS anyway because of the interesting features it gets (deduplication for example).

I'm pretty confident now that if PVE can perform backup while VM is up (as you said), PBS can do it but I want to make sure and ask again (sorry for being annoying ):

- Do PBS have this fonctionnality?

(We will use PBS with Proxmox version 7.3 and with raw files for the VMs where they are stored in an NFS storage.)

Thank you again for your help!

 

[fiona]

I'm pretty confident now that if PVE can perform backup while VM is up (as you said), PBS can do it but I want to make sure and ask again (sorry for being annoying ):

- Do PBS have this fonctionnality?

Yes, for classical vzdump backup and PBS backup, similar mechanisms are used to handle the VM itself. So you can backup running VMs. The backup data will be transferred differently of course.

(We will use PBS with Proxmox version 7.3 and with raw files for the VMs where they are stored in an NFS storage.)

Please note that Proxmox VE 7 is end-of-life since the end of July. It is highly recommended to upgrade:
https://pve.proxmox.com/wiki/Upgrade_from_7_to_8