Re: btrfs based backup?

["Austin S. Hemmelgarn" <ahferroin7@gmail.com>]

On 2019-11-12 13:34, Ulli Horlacher wrote:
> 
> I need a new backup system for some servers. Destination is a RAID, not
> tapes.
> 
> So far I have used a self written shell script. 25 years old, over 1000
> lines of (HORRIBLE) code, no longer maintenable :-}
> 
> All backup software I know is either too primitive (e.g. no versioning) or
> very complex and needs a long time to master it.
> 
> My new idea is:
> 
> Set up a backup server with btrfs storage (with compress mount option),
> the clients do their backup with rsync over nfs.
> 
> For versioning I make btrfs snapshots.
> 
> 
> To have a secondary backup I will use btrfs send / receive,
> 
> 
> Any comments on this? Or better suggestions?
> 
> The backup software must be open source!
> 

Borg [1] backup on the clients. That will get you:

* Automatic 'versioning' without needing snapshots.
* Automatic compression and deduplication of the backups (without 
needing BTRFS to do either).
* Automatic encryption (if you want it).
* The ability to mount your backups like a filesystem (through FUSE).
* All in a layout that's reasonably friendly to copy between systems 
with tools like rsync or rclone.

Borg's big thing is that it does reference-counted deduplication of the 
individual blocks of the backup, so incrementals take up next to no 
space or time but still give you a full view of the backed up filesystem 
with each snapshot. It also has support for accessing a backup server 
over SSH, which is a bit more efficient than using something like NFS.

For the copy to the secondary backup, you could just use rsync to mirror 
the backups done with Borg (or alternatively, us rclone to mirror them 
offsite to cloud storage).

[1] https://borgbackup.readthedocs.io/en/stable/