Re: [PVE-User] Proxmox Backup Server (beta)

[Alexandre DERUMIER <aderumier@odiso.com>]

>>Proxmox Backup Server effectively does that too, but independent from the
>>source storage. We always get the last backup index and only upload the chunks
>>which changed. For running VMs dirty-bitmap is on to improve this (avoids
>>reading of unchanged blocks) but it's only an optimization - the backup is
>>incremental either way.

What happen if a vm or host crash ? (I think on clean shutdown, the dirty-bitmap is saved, but on failure ?)
does it need to re-read all blocks to find diff ? or make a new full backup ?

Is it possible to read files inside a vm backup, without restoring it first ?
(Don't have check vma format recently, but I think it was not possible because of out of orders blocks)


I really think it could be great to add some storage snapshot feature in the future.
For ceph, the backup speed is really faster because it's done a bigger block than 64K. (I think it's 4MB object).
and also, I really need a lot of space for my backups, and I can't fill them in a single local storage. (don't want to play with multiple datastores)
Bonus, it could also be used for disaster recovery management :)


But that seem really great for now, I known a lot of people that will be happy with PBS :)
Congrats to all proxmox team !


----- Mail original -----
De: "Thomas Lamprecht" <t.lamprecht@proxmox.com>
À: "aderumier" <aderumier@odiso.com>, "Proxmox VE user list" <pve-user@lists.proxmox.com>
Envoyé: Mardi 14 Juillet 2020 17:52:41
Objet: Re: [PVE-User] Proxmox Backup Server (beta)

Hi, 

On 14.07.20 16:30, Alexandre DERUMIER wrote: 
> I don't have tested it yet and read the full docs, 

The following gives a quick overview: 
https://pbs.proxmox.com/docs/introduction.html#main-features 

> 
> but it is possible to do ceph to ceph backup with ceph snapshots (instead qemu bitmap tracking)? 

No. ceph, or other storage snapshots, are not used for backup in PBS. 

> 
> Currently in production, we are backuping like that, with incremental snapshot, 
> 
> we keep X snapshots on ceph backup storage by vm, and production ceph cluster only keep the last snasphot. 
> 
> The main advantage, is that we are only doing a full backup once, then incremental backups forever. 
> (and we have checkum verifications,encryption,...) on ceph backup 

Proxmox Backup Server effectively does that too, but independent from the 
source storage. We always get the last backup index and only upload the chunks 
which changed. For running VMs dirty-bitmap is on to improve this (avoids 
reading of unchanged blocks) but it's only an optimization - the backup is 
incremental either way. 

> We can restore full block volume, but also selected files with mounting the volume with nbd. 

There's a block driver for Proxmox Backup Server, so that should work just 
the same way.