Re: [rdiff-backup-users] rdiff-backup-regress script query - need to be 'nobody' or 'root'

[Dominic Raferd]

On 23 June 2017 at 12:53, Ron Leach <address@hidden> wrote:

> List, good morning,
>
> Having messed up the latest backup increment of our quite-large filesystem
> and, having long been a very happy user of Dominic's rdiff-backup-regress
> script, I thought I'd better regress the messed-up increment.
>
> On running the regress script as user 'ron', the script advised that I
> needed to be user 'nobody' or 'root'.  But, after su-ing to root, the
> script warned me:
>
> address@hidden:/home/ron# ./rdiff-backup-regress.sh -n 1
> /mnt/backserver/Backups
>
> rdiff-backup-regress.sh v1.0 [25 Aug 2016] by Dominic (-h for help)
> =======================
>
> You are user 'root', not 'nobody', which may result in changed ownership
> of some files.
> Are you sure you wish to continue (y/-)? n
> Exiting, no changes made
> address@hidden:/home/ron#
>
> I've not had this warning before.  Many of the files in this backup are
> used by MS Windows clients, and managed by samba; I think this may be where
> the 'nobody' user is coming from.  The files are also served over NFS to
> linux clients, perhaps they are marked as 'nobody'.
>
> I think I ought not mess up the file ownerships, so I wanted to take heed
> of the script's warning.  I don't know how to become user 'nobody' - I
> don't think there is a 'nobody' password.
>
> Before I dig a deeper hole, has someone else bumped into this when using
> rdiff-backup-regress script and (if so) what did they find was the best way
> forward?  I probably do need to regress this increment, really.
>
> Grateful for any comment,


​Hi Ron, I'm glad my script has helped you in the past. The warning is from
my script, not from rdiff-backup and was based on my experience. The safest
way to run the script IMO is as user nobody i.e. the same user as created
the archive, ​you might have to create a password temporarily for this user
and then remove it afterwards. If you run it as root there is a risk that
some files in the repository are left readable and/or writeable only by
root so future rdiff-backup sessions by the original user could fail. If
you have to run the regression as root I advise taking a backup of the
entire repository beforehand. Unless anyone knows different?