Backup Central

On Sat, 6 Aug 2005, Ben Escoto wrote:

dean gaudet <dean-list-rdiff-backup < at > arctic.org>
wrote the following on Wed, 20 Jul 2005 12:30:59 -0700 (PDT)

i'm tempted to change it so that a command line option is required
to enable the mode futzing... by default i'd really prefer backup
and restore sources be completely read-only.

Well I'd prefer that the default behavior stay the same. It is
somewhat unfortunate, but by default the setup I mentioned above
should work.

actually in the case of the mirror copy there's technically no longer any
need for the modes to be correct -- thanks to the metadata files... i'm
doing all my backups using a non-root user on the backup server (obviously
still need root on the host being backed up). in this case i'd really
rather be loose with the mode on the mirror and thus ensure restores never
need to write the mirror.


Does it still mess with the permissions when run as root? As root I
would hope it realizes it doesn't need to change anything.

i hope it doesn't... but yeah i don't know, i haven't looked lately. (on
slow dialup now or i'd probably do some hacking :)

-dean

dean gaudet <dean-list-rdiff-backup < at > arctic.org>
wrote the following on Wed, 20 Jul 2005 12:30:59 -0700 (PDT)

On Wed, 20 Jul 2005, Sheldon Hearn wrote:

If we're not root on the server during a restore operation, we try to
change permissions to ensure readability? Either we can read an object
or we can't. If we can't, it's _highly_ unlikely that we'll be able to
change permissions on it anyway.

only root can read mode 0 files ... this code exists so that if you're
non-root you can backup and restore mode 0 files which you own... but it
is kind of unfortunate, isn't it?

Yes, exactly. This code is conceptually messy and has been a source
of errors in the past, but I think it's working correctly in this
instance.

For instance, suppose you (or your pesky users) on computer A make
some directories then set the perms to 0. Then you as root on
computer A back up those directories to a non-root account on computer
B. For this to work when restoring the non-root account on computer B
will have to increase the permissions in order to read stuff and then
reset them as it leaves.

Before rdiff-backup would attempt to do this to the source partition
when backing up, but fortunately it doesn't do this any more. (I
admit this was a bad idea--it led to someone losing their whole source
directory!)

i'm tempted to change it so that a command line option is required
to enable the mode futzing... by default i'd really prefer backup
and restore sources be completely read-only.

Well I'd prefer that the default behavior stay the same. It is
somewhat unfortunate, but by default the setup I mentioned above
should work.

Does it still mess with the permissions when run as root? As root I
would hope it realizes it doesn't need to change anything.


--
Ben Escoto