Unable to mitigate source mismatch

[Tom Slominski]

Hi. I'm trying to backup my home directory to an external hard drive, excluding a few directories: ['$TRASH', '$DOWNLOAD', '/home/tom/.steam', '/home/tom/.cache', '/home/tom/Dropbox']. After entering my encryption password, I get the following error (cut from log):

DUPLICITY: ERROR 42 '/' '/home/tom'
DUPLICITY: . Fatal Error: Backup source directory has changed.
DUPLICITY: . Current directory: /
DUPLICITY: . Previous directory: /home/tom
DUPLICITY: .
DUPLICITY: . Aborting because you may have accidentally tried to backup two different data sets to the same remote location, or using the same archive directory. If this is not a mistake, use the --allow-source-mismatch switch to avoid seeing this message

That is blatantly incorrect, as I'm backing up /home/tom only. Maybe something inside .steam or .cache symlinks to /? Either way, Deja Dup should offer the user the option to bypass this using "--allow-source-mismatch".

I'm using Ubuntu Gnome 14.04.
deja-dup 30.0-0ubuntu4
duplicity 0.6.23-1ubuntu4

[Mark Stosberg (markstos)]

I can confirm that with Ubuntu 17.10 it's still possible to get this error and there is not a way to mitigate it.

I triggered it by trying to workaround another bug in Deja Dup-- https://bugs.launchpad.net/duplicity/+bug/1642544

My temporary solution was to run some manual backups directly with "duplicity". I guess I ended using different source setting, which then triggered this condition when trying "Deja Dup" again.