Re: Using rsync to disk on the system being backed up?

[rhkramer]

On Wednesday, February 15, 2023 01:24:16 PM ewl+rdiffbackup@lavar.de wrote:
> rdiff-backup (rdiff is something different) actually uses the
> patching/delta approach of (lib)rsync also locally to store less data.

I guess I should have given more context (or clarity) to my questions.

Part of my question was intended to be: if I don't have rdiff-backup available 
(for whatever reason), can I use fairly standard tools (e.g., patch) to 
retrieve older versions that I've backed up.

If rdiff-backup is storing less data, maybe it is not enough for patch to work?

If that is not the case (if rdiff-backup) is storing data just like would be 
created by a fairly standard (reverse) diff (of whatever flavor, e.g., unified 
or 
whatever), I don't see any benefit to using something like rsync to communicate 
with a disk on the same computer (for the case when I am backing up to a(n 
internal or external disk) on the computer being backed up.

> On 15 February 2023 19:16:50 GMT+01:00, Robert Nichols 
<rnicholsNOSPAM@comcast.net> wrote:
> >On 2/15/23 10:35, rhkramer@gmail.com wrote:
> >> I've googled enough to find out that rdiff at least in some
> >> circumstances uses rsync to minimize communication bandwidth.
> >> 
> >> My question is this: if rdiff-backup is backing up to a disk (internal
> >> or external) on the machine being backed up, does it continue to use
> >> rsync?
> >
> >When working over a network link, rdiff-backup works in a manner _like_
> >rsync. It doesn't actually use the rsync program. When backing up to a
> >local disk, it of course accesses the disk directly.
> >
> >OK, I suppose if you really wanted to simulate networked operation when 
working locally you could run:
> >    rdiff-backup backup {source directory} localhost::{archive directory}

-- 
rhk 

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