Re: [rdiff-backup-users] sshfs: workaround and test results

[Andreas Olsson]

On Sunday 06 January 2008 14:09:55 Andreas Olsson wrote:
> On Sunday 06 January 2008 12:43:43 Andreas Olsson wrote:
> > Anyhow, with that workaround all the tests I have run against a
> > sshfs-mount have worked really well. No errors to report.
>
> Well, it seems as if I didn't run enough tests before I wrote that :-)
>
> If you run rdiff-backup as a normal user (none-root) against a sshfs-mount
> where the files are owned by a different UID on the remote host, then there
> can be some issues. I will return when I've had time to look more into it.

Here comes an output on what works and what doesn't work when you run 
rdiff-back as a normal user and the uid on the other side of the sshfs differs

address@hidden:~$ rdiff-backup --no-hard-links temp/source/ mnt/remote/
address@hidden:~$ echo foo > temp/source/newfile
address@hidden:~$ rdiff-backup --no-hard-links temp/source/ mnt/remote/
address@hidden:~$ echo bar >> temp/source/newfile
address@hidden:~$ rdiff-backup --no-hard-links temp/source/ mnt/remote/

address@hidden:~$ rdiff-backup -l mnt/remote/
Fatal Error: Bad directory mnt/remote.
It doesn't appear to be an rdiff-backup destination dir
address@hidden:~$ rdiff-backup --verify mnt/remote/
Fatal Error: Bad directory mnt/remote.
It doesn't appear to be an rdiff-backup destination dir
address@hidden:~$ rdiff-backup -r now mnt/remote/ temp/restore/
Fatal Error: Could not find rdiff-backup repository at mnt/remote
address@hidden:~$ rdiff-backup 
mnt/remote/rdiff-backup-data/increments.2008-01-07T01\:11\:11+01\:00.dir 
temp/restore/
Fatal Error: Source 
mnt/remote/rdiff-backup-data/increments.2008-01-07T01:11:11+01:00.dir is not a 
directory

address@hidden:~$ mkdir temp/local
address@hidden:~$ rsync --archive mnt/remote/ temp/local/

address@hidden:~$ rdiff-backup -l temp/local/
Found 2 increments:
    increments.2008-01-07T01:11:11+01:00.dir   Mon Jan  7 01:11:11 2008
    increments.2008-01-07T01:11:34+01:00.dir   Mon Jan  7 01:11:34 2008
Current mirror: Mon Jan  7 01:12:36 2008
address@hidden:~$ rdiff-backup --verify temp/local/
Every file verified successfully.
address@hidden:~$ rdiff-backup 
temp/local/rdiff-backup-data/increments.2008-01-07T01\:11\:11+01\:00.dir 
temp/restore/

In short it seems as if write operations work, but not read operations.
Obviously you can actually read all the files, just that rdiff-backup 
somehow seems to think it can't?

A workaround for this trouble seems to be to specify your 
local uid when you do you sshfs-mount. (-o uid=LocalUID)

This is the part where I perhaps should write a few words about sshfs-mounts
 for those of you who aren't familiar with it. When you normally do a 
mount the remote files shows up as owned by the remote uid, which 
can be a completly diffrent user on your system. You still have full 
access to the files in question thought. When mounting with the 
option above the files actually lists as being yours.

I wonder if this isn't something which might be fixed in rdiff-backup? 
Without actually understanding what is happening inside the program 
it seems more like that it doesn't think that it can read the files in 
question then that it can't read them for real.

-- 
Andreas Olsson
http://www.andreasolsson.se/

signature.asc
Description: This is a digitally signed message part.