Backup Proxmox - Data in VMs?


New Member
Jul 9, 2019
First of all, I´m very sorry if this question is borderline retarded or anything - I´m a complete beginner with anything that isn´t windows... So I hope you can be patient and explain it at my level ;)
Second, I´m also not an english native, so please excuse any mistakes.

I got my hands on the old server from my office, it´s nothing fancy but it now sits in my cellar. I set up Proxmox, and managed to setup a few VMs there with the help of tutorials (mostly youtube).
Currently it runs
-Unifi controller
-and most important, Nextcloud,

along with a few others that are not important and mostly for experimenting.

So, recently I also got my hands on a bit of additional storage that I want add.
Here´s the thing though: My server uses a HARDWARE Raid controller.
So, if I want to add additional (SAS) disks to this controller, I probably have to wipe proxmox and set it up completely from scratch anew, right?

Of course, I don´t want to lose all the data on Nextcloud, especially b/c it´s not only mine, but also from several family members.

Thus, I need a backup.

But what do I backup - is it enough if I have a Proxmox backup? If there´s a backup of the Nextcloud VM, are all the data ON the nextcloud also save, and I can simply restore everything?

OR is it better to do a seperate backup of Nextcloud, wipe Proxmox, create a new Nextcloud VM and then restore the old Nextcloud content?

I´m glad for ANY help you can provide.

Many thanks in advance!


First of all, if your hardware RAID supports it (probably does, haven't heard of one that would delete existing pools), you can simply add your new drives and create a new array in your RAID controller configuration. It will then show up as a second disk on your existing Proxmox Install. You could then go to your VMs "Hardware" section, select your disk and choose "Move Disk" at the top to migrate it to your new storage (if that's what you want).

Of course, having backups is still a very good idea. If you use the integrated backup tool in the Proxmox VE Web Interface (Go to your VM -> Backup -> Backup Now), all data of your VM will be backed up. This includes all files stored on the disk of the VM, so your Nextcloud Data too.

I recommend storing the backup on an external medium, or at least on a different disk than your main install. Maybe that would be a good use case for your new drives? :)
Cool, ill try that and hope for the best :)
I didnt want to mess with the RAID config, thought it might wreck something. I´ll try on the weekend and report back, hopefully with good news.


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