Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 24 Aug 2005 14:37:08 -0700
From:      Danny Howard <dannyman@toldme.com>
To:        Scott Mitchell <scott+lists.freebsd@fishballoon.org>
Cc:        Ilari Laitinen <ilari.laitinen@iki.fi>, questions@freebsd.org
Subject:   Re: dump(8), incremental backups, Tower of Hanoi sequence, don't get it
Message-ID:  <20050824213708.GT51748@ratchet.nebcorp.com>
In-Reply-To: <20050824113237.GA68101@llama.fishballoon.org>
References:  <20050819141535.GA62513@lohi.local> <20050823182133.GF51748@ratchet.nebcorp.com> <20050823112716.U26292@wolf.pjkh.com> <20050824113237.GA68101@llama.fishballoon.org>

next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Aug 24, 2005 at 12:32:38PM +0100, Scott Mitchell wrote:

> Another useful rsync option is --link-dest:
> 
> --link-dest=DIR
>       This  option  behaves  like --copy-dest, but unchanged files are
>       hard linked from DIR to the destination  directory.   The  files
>       must be identical in all preserved attributes (e.g. permissions,
>       possibly  ownership)  in  order  for  the  files  to  be  linked
>       together. 
> 
> I use this to rsync each backup into a new directory on the backup volume,
> named for the date of the backup.  The result is a directory for each backup
> run, apparently containing every file from the source tree - but most of them
> are just hard links to some previous backup.  This saves a *lot* of disk
> space as you only ever copy files that have changed since the last backup.
> You also have the complete file tree for each backup, so it's trivial to
> restore the version of a file that existed on any particular date.

All this great discussion got me researchinng.  I haven't tried this
out but it looks like rsnapshot integrates a lot of features like this
into a single configurable, cronable script.  It is in ports as well.

A lot of systems make use of cp -al ... well, for us FreeBSD people that
means gcp from coreutils.

rsnapshot looks like a lightweight, OS/FS-portable method of building
rotating filesystem-wide snapshots via hardlinks, but can be made to
operate on limited sets of directories, etc.  It can create local
snaphots of remote directories, but not, apparently, remote copies of
local directories.  One trick I gleaned from
http://burd.info/gary/2003/03/snapshot-backup-using-rsync-and-ssh.html
is to invoke rsync with --rsync-path which points to a script which
performs maintenence functions and then passes off to rsync proper, so
you could probably set up a client-triggered rsnapshot configuration if
you were, say, doing backups of a Windows laptop client. :)

-danny

-- 
http://dannyman.toldme.com/



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20050824213708.GT51748>