[CentOS] Rsync and differential Backups

Mon Nov 9 22:19:39 UTC 2015
Frank Thommen <lists.centos.de at drosera.ch>

Ciao Alessandro,

On 11/09/2015 05:01 PM, Alessandro Baggi wrote:
> Hi list,
> how to perform a differential backup using rsync?
>
> On web there is a great confusion about diff backup concept when
> searched with rsync.
>
> Users says diff because it copy only differences. For me differential is
> backup from last full backup.

Which is basically the same...if you always use your last full backup as 
"base" directory.  Use rsyn's --link-dest option to achieve this.  Nice 
thing: Unchanged files will just be hardlinked to the original files and 
won't use additional disk space, but still each dataset is a coopmlete 
backup.  There is no need to combine several incremental or differential 
backups to restore a certain state.

Mike Rubel's page has already been mentioned.  On 
http://www.drosera.ch/frank/computer/rsync.html I describe an alternate 
mechanism (using above mentioned --link-dest and an rsync-server) which 
overcomes some of the - imho - shortcomings of Mike's setup.

And: rsync is a fan-tas-tic backup tool ;-)

HTH
Frank