[CentOS] evaluating backup systems: rsync

[ken]

On 01/11/2013 02:33 PM m.roth at 5-cent.us wrote:
> ken wrote:
>> On 01/11/2013 12:36 PM Les Mikesell wrote:
>>> On Fri, Jan 11, 2013 at 11:29 AM, ken<gebser at mousecar.com>   wrote:
>>>> Considering using rsync on a couple systems for backup, I was wondering
>>>> if it's possible, and if so how difficult is it, to delete files which
>>>> have been backed up (in order to save space on the backup media).
>>>>
>>>> Anyone with experience doing this?
> <snip>
>> Les, thanks for replying.  Yeah, I guess I need to clarify.
>>
>> I've got a system which is due for an upgrade and, at the same time,
>> would like to clean up (delete) files and, in some instances, entire
>> directories.  Insurance against sudden disk failure is one other concern.
>>
>> If I delete files and entire directories on that (source) machine, will
>> rsync then subsequently automatically delete them on the destination
>> (backup) system?  Or would I need also to run an rsync command to delete
>> the same on the destination system?  And, if yes, what rsync command
>> would do that?
>>
>> I remember you speaking well of Backuppc previously and so am open to
>> using that in future.  At the moment though, I'm looking for the
>> simplest possible solution for those three current concerns.
>
> We use rsync here. Actually, we've got a home-rolled system. We created
> timestamped backups, which also removes them after a configuration file
> item of how many days or weeks. Note that we *heavily* use rsync's parm to
> use hard links, which saves a lot of space.
>
>         mark

Cool.  Thanks for mentioning time-stamps.  I've been assuming that rsync 
would maintain the source files' original permissions and timestamps. 
(Heck, even tar from decades past would do that.)  I hope that wasn't an 
unwarranted assumption.  It's good to hear too that I can configure how 
long to keep files on destination which have been deleted from the 
source (if that's what you meant).

Mark, maybe you could explain what a "parm" is and how using hard links 
saves space.


tia,
ken