Gentoo Archives: gentoo-user

From: Nganon <nganon+gentoo@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] How to build a time machine on Gentoo
Date: Wed, 18 Aug 2010 17:57:32
Message-Id: AANLkTim_xoOxd3oFHyVnnxaD9-U-BZOV6g87+rc7mde0@mail.gmail.com
In Reply to: Re: [gentoo-user] How to build a time machine on Gentoo by William Kenworthy
1 On 18 August 2010 14:59, William Kenworthy <billk@×××××××××.au> wrote:
2
3 > On Wed, 2010-08-18 at 14:09 +0300, Nganon wrote:
4 > >
5 > >
6 > > On 17 August 2010 22:34, Enrico Weigelt <weigelt@×××××.de> wrote:
7 > > For things I'd like to keep an history (eg. /etc) I'm using
8 > > git, and
9 > > pushing the repo to a remote server (denying non-fastfoward
10 > > updates
11 > > there, so an theorectical highjacker cannot destroy my
12 > > history)
13 > >
14 > >
15 > > Using git for /etc is a great idea.
16 > > Thanks.
17 > >
18 > Another option is:
19 > * app-backup/dirvish
20 > Latest version available: 1.2.1
21 > Latest version installed: 1.2.1
22 > Size of downloaded files: 47 kB
23 > Homepage: http://www.dirvish.org/
24 > Description: Dirvish is a fast, disk based, rotating network
25 > backup system.
26 > License: OSL-2.0
27 >
28 >
29 > Works by first creating a copy (--init) and then hard-linking subsequent
30 > versions of files/directories back to the original original if its
31 > identical. If a file is changed/new, it is copied instead of linked so
32 > actual space usage quickly stabilises even with a varying number of
33 > versions. Backup over the network (this is how I have configured mine)
34 > uses rsync over ssh with keys and is "pull" from a cron job on the
35 > backup server or manual on demand (i.e., server initiated).
36 >
37 > Version management is by a reasonably sophisticated date of version
38 > scheme where by running "dirvish-expire" deletes out of date versions
39 > (runs in a cron job). The smart part is that once the last hard link to
40 > file is deleted, its gone, otherwise its kept in the remaining
41 > versions :)
42 >
43 > Restore is a simple matter of identifying the version you want and
44 > copying it back - Ive restored individual files through to complete
45 > systems after total disk failure.
46 >
47 > Can do includes/excludes, whole systems or just directories such as /etc
48 > and can be easily automated.
49 >
50 > Doesnt use compression, but most backup regimes (every day for a weekly
51 > rota + a Sunday kept for 6 months) stabilise at about 2x the original
52 > (gross) copy size, no matter how many copies with average changes
53 > between versions. Though large scale changes such as an "emerge -e
54 > world" will take more as it will generate new copies of most files.
55 >
56 > Downside is it will hammer the destination file system - reiserfs3 works
57 > well, ext2/ext3 have been hopeless everytime I've tried - mass
58 > corruption. The file system will need a large number of inodes (for
59 > links) if there are an excessive number of files x versions - again
60 > reiserfs3 scores well here.
61 >
62 > Highly recommended!
63 >
64 > BillK
65 >
66 >
67 >
68 >
69 Thanks. It sound just it is made just for this. It even call itself 'time
70 machine'.
71 Obviously compression is left out by using links but it sounds kind of
72 overwhelming to me. I don't have a reiserfs partition and cannot afford to
73 have one at the mo..