Re: [rdiff-backup-users] Removing intermediate snapshot

[Jacob Anawalt]

> On 04/02/2011 12:00, Alex Schuster wrote:
>
> For my
> /home directory, the last backup is most important of course, but I would
> also like to be able to restore the very first backup I did make.  All other
> backups in between are not that important, and I would like to remove some.

You could restore that fist version to a different location, back it
up on a long term storage media, then use --remove-older-than. You
would of course no longer use rdiff-backup to restore that first
version.

> But rdiff-backup only has a --remove-older-than<date>  option, not something
> like --remove-between<date1>  <date2>. Is there some workaround,

rdiff-backups uses reverse diffs. The most recent file is complete.
Historical versions are a chain of dependent reverse diffs. Removing
interim backups yet keeping an older version would require restoring
the versions on either side of date1 and date2 and repacking a reverse
diff of that change and rewriting all the metadata history referring
to file during the in between range to pretend it didn't exist or
didn't change. Otherwise the versions before the older date may be
worthless.

> or do I want the impossible?
>

Seems tricky and may have unintended consequences. (Insert
back-to-the-future warning of choice here :) ) The subversion project
skirts the issue by requiring you to dump, filter, and re-import. It
isn't something I would want to tackle even though I've thought it
would be nice once or twice.

> I'm expecially concerned about one backup that has very much data in it that
> was only temporary and is no longer needed. I read I could remove those
> specific files if I am careful,

http://www.nongnu.org/rdiff-backup/FAQ.html#remove_dir
http://wiki.rdiff-backup.org/wiki/index.php/FAQs#How_do_I_remove_files_from_the_backup_set_.2F_I_didn.27t_like_answer_.238_in_the_official_FAQ

Also tricky. Best of luck,
-- 
Jacob