Why Use Proxmox Backup on TrueNAS Instead of Direct Backups

[cortes]

After setting up my Proxmox VE server, I looked into Proxmox Backup. Since I wanted to backup my other systems (two MacOS devices), I decided on TrueNAS as a more general purpose solution and an excuse to have a file server. I then did a search on backing up Proxmox VE to TrueNAS and mainly got hits on running Proxmox Backup on TrueNAS. I did eventually find a description of backing up to a share. My question is why would you want to run Proxmox Backup on TrueNAS when you can backup directly to it? Isn't just an additional layer of complexity? Is there some advantages to PMB that I'm missing?

 

[UdoB]

Is there some advantages to PMB that I'm missing?

You probably read the product description, but you did not mention: silently working deduplication. PBS chomps your large backups files into chunks. Iirc it is 4MiB in size. These chunks are deduplicated. This mechanism has nothing to do with ZFS dedup but also works on a (not recommended) NFS store or any other filesystem. For this to function properly rotating rust is too slow under some conditions - this is why "they" recommend SSDs as the underlying technology.

My PBS shows me a factor of 40. This means currently I actually do store 100 TB of backups while occupying less than 3 TB.

For me this means in this very moment: ~120 VMs backuped in 2500 "full backups" with a long history. But I must stress: your mileage may really vary!

Best regards

PS: TrueNAS and also PBS wants to get installed on bare metal. Implementing them into a virtual machine is always a compromise and not really recommended...

 

[danb35]

This is really a Proxmox question more than a TrueNAS question, and as such you'd probably find better answers in the Proxmox forums--though you'll also likely be told there that (1) as already mentioned, running PBS on bare metal is recommended rather than as a VM, and (2) using a file share as backup storage for PBS is discouraged.

But with that said, yeah, deduplication. I'm seeing a ratio roughly 30:1.

 

[cortes]

This is really a Proxmox question more than a TrueNAS question, and as such you'd probably find better answers in the Proxmox forums--though you'll also likely be told there that (1) as already mentioned, running PBS on bare metal is recommended rather than as a VM, and (2) using a file share as backup storage for PBS is discouraged.

But with that said, yeah, deduplication. I'm seeing a ratio roughly 30:1.

Deduplication of that scale is certainly an advantage and running PBS on bare metal makes sense. Why is backing to TrueNAS an issue? I'd ask on the Proxmox forums, but I've never got answers to any of my previous questions even with a subscription.

 

[danb35]

Why is backing to TrueNAS an issue?

I recall that it's recommended against, but not particularly why--though I'm sure performance is at least part of the reason.

 

[mindio]

Does anyone use zfs dedup on TrueNAS for this task? I am currently passing truenas nfs share to proxmox and using this for pve vm's backup. But how truenas dataset with dedup would be efective for this?

 

[Jamberry]

Here is my thinking on why a Proxmox Backup Server could be a good addition to ZFS sync:
Despite me loving ZFS, I think it is a good idea to not relay on a single system.
I have a Proxmox Server with ZFS. Thanks to ZFS I can create snapshots as a backup. Yeah I know that snapshots are not a real backup, but the cool thing about Snapshots is that they are extremely fast don't use much space. So you basically get the advantage of PBS without the performance hit. Before an update, or any other little change I will create a snapshot. It is just so easy to roll back if you or an update messed something up.

But because Snapshots are not a backup, I also create normal Proxmox backups that are saved on a TrueNAS NFS share (and from there synced to the cloud).

Now to create an off site backup that is not on the cloud, I see two options.
I could either go with ZFS send and just copy the snapshots to another host or I could setup a remote Proxmox Backup Server.
Because I already rely on ZFS for the local Snapshots, I feel more at ease by using PBS. It feels like a different media that follows more "two different media" of the 3-2-1 rule.