Re: OK to take hourly snapshots, then cull older ones?

["Matthias G. Eckermann" <matthias.g.eckermann@t-online.de>]

Hello Marc and all,

On Mon, Nov 04, 2013 at 06:51:11PM -0800 Marc MERLIN wrote:
> On Sun, Nov 03, 2013 at 12:50PM +0100, Matthias G. Eckermann wrote:
> > On Mon, Oct 14, 2013 at 21:05 David Madden wrote:
> > 
> > > I'd like to use BTRFS to do something like the old NetApp
> > > snapshot system: every hour or so, there'd be a snapshot,
> > > then the 23 of the snapshots during a day would be
> > > deleted, leaving just a day snapshot, then after a month,
> > > 6 of 7 snapshots would be deleted, leaving just a week
> > > snapshot, and so on.
> > 
> > This is implemented in "Snapper", see:
> > 	http://snapper.io/
> > It's by default delivered with openSUSE and SUSE Linux
> > Enterprise, binaries are available for "everything else"
> > as well.
> 
> Just curious, what does it do more than the 20 line shellscript I
> posted?
> http://marc.merlins.org/linux/scripts/btrfs_snaps

You asked ... 

Snapper does not only handle snapshotting itself, but a
lot of steps around it, to make it easier for an
administrator to handle snapshotting.

While primarily offering a cmdline utility, Snapper also
has integration into D-BUS, thus other tools can ask for
snapshots on a specific subvolume.  To make this secure,
access rights are stored in a per subvolume configuration
among other attributes and rules.

Based on that Snapper offers (rough summary):

- Managing configurations (create, delete, list, ...)
- Managing snapshots (create, delete, list)
- Add and modify metadata of snapshots
- Compare snapshots aka "diff"
- Roll-back snapshots (selective roll-back, per file)

Within the configuration you can add
- rules for creation and removal of snapshots
- access rights

Off-Topic: Snapper also works with DM based snapshots.

Other projects using snapper:

* Samba 4 has a prototype implementation of Windows'
  FSRVP server for SMB share shadow-copies ("snapshots") 
  using Snapper via D-Bus. See: 
  http://snapper.io/videos.html

* The Systems Management stack of openSUSE / SUSE 
  Linux Enterprise (ZYpp, YaST) uses Snapper
  automatically, if "/" is on btrfs.

<SelfAdulation>

One also can use it for regular snapshots to the $HOME
directory; see my description here:
https://www.suse.com/communities/conversations/menu-du-jour-vivaneau-vert-sur-lit-de-legumes-au-beurre-et-supremes-de-pamplemousse-2/
and here
https://www.suse.com/communities/conversations/sieste-siesta/

</SelfAdulation>

Hope this explains.

so long -
	MgE

-- 
Matthias G. Eckermann, Berlin, Germany
Private : matthias.g.eckermann@t-online.de
Business: mge@suse.com