Backup 2 disks from the same VM with different retentions

[yoshimanly]

Hey, I'm stumped, I've been trying to find a way to backup 2 disks from the same VM with different retentions.
I have a situation where the VM has a huge disk that has to be backed up with less retention then the OS disk because the NAS where is being backed up to doesn't have enough storage. Upgrading the NAS is not an option at this point and the backup is critical.

I'm running proxmox 7.1.7, with lvm-thin

Help would be very appreciated

Edit:
TLDR: To who is coming here with the same question, no it's not possible, PBS is the only option since it does deduplication.

 

[Dunuin]

Maybe you could use PBS instead of Vzdump? Won't allow you to use different retentions for different disks but because of deduplication it is way more space efficient as nothing has to be stored more than once. So if your VM got a big disk and you want multiple backups of it, it wouldn't use much more space than a single backup...atleast not if the data isn't changing that much. So with PBS it isn't that important how much backups you keep and it might be fine to have the same backup retention for both disks.

 

[yoshimanly]

I just explored that idea (spun up a VM with NFS share as dataset) since I made the post. Unless I'm missing something, running as a VM is not great and mount the storage as NFS is not great to, since new hardware for now isn't an option I'm in a difficult position. For clarification, it's just one server and one QNAP, I do have backups of everything off-site, but for a speedy recovery, it would be nice to have a local copy.

In case of total failure, if I reinstall the PBS machine, would I be able to just mount the NFS or SMB share and just pickup the dataset where it left off?

 

[Dunuin]

You can use Vzdump to backup your PBS VM first and store it on the NAS. Then use that restored PBS VM (which accesses the datastore ober NFS/SMB frm NAS too) to restore the other VMs. What might not be great is the time of the maintaince tasks. Especially verify jobs take long. And a ZFS pool with a pair of SSDs tostore the metadata would help alot with the GC tasks.

Not sure if your QNAP can run VMs too. Here my PBS runs on the TrueNAS server inside a VM (2-3 cores and 2-3GB RAM is fine here for the VM).

 

[yoshimanly]

Thank you for your answer, I can't really complain ! It is a solution and it's sad that PBS is the only option to being able to deduplicate or to have 2 disks from the same VM with different retentions(I mean not even that is possible by the looks of it). That's a bit to convoluted for comfort and I might just move that big disk to another VM and resolve the issue. VZdump unfortunately is lacking a lot, and probably on propose... Anyway, thank you very much for your time

 

[yoshimanly]

Not sure if your QNAP can run VMs too. Here my PBS runs on the TrueNAS server inside a VM (2-3 cores and 2-3GB RAM is fine here for the VM).

It's a old QNAP, I'm pretty sure it can't. I did thought in doing it that way on my home setup, but I have so much storage that I can afford to no deal with deduplication headache and the overhead. At this point I'm getting a bit sick of the short comings off proxmox. I will probably move to VMWare or XCP-NG someday.

My problem is on a client setup, later when I get some experience with one of those, I'll move the client to