[Duplicity-talk] Debugging SFTP connectivity issues and showing SFTP output

[Mikko Ohtamaa]

Hi,

I am running Duplicity (wrapped in Duply) backup scripts in a Hetzner
(hetzner.de) hosted environment. Mostly backups run fine, but on a
certain server I have SFTP connectivity issues I am unable to debug.
Hetzner provides a special backup space option which is accessible
over SFTP (not sure what SFTP server they are running there).

SFTP command seems to abort now and then and I have not found a way to
make Duplicity to generate useful output (tried -verbosity '9') to see
what happens when things go wrong. The problem is random, so it is
pretty much impossible to repeat it by hand: if you SFTP upload
yourself it always success.

Is there a way to make Duplicity to dump out SFTP output, so one could
get some useful information what is wrong with SFTP (network problem,
local issue, some magical with the file, etc.) The connection is
definitely dropped, but I'd like to find out what's causing it :(

Command:

TMPDIR='/tmp' duplicity --name 'duply_fullbackup' --no-encryption
--verbosity '9' --full-if-older-than 1M --volsize 250
--exclude='**.log' --exclude='**.fs.old' --include=/etc
--include=/home --include=/root --include=/srv --include=/var/www
--include=/boot --exclude=/** --exclude-globbing-filelist
/root/.duply/fullbackup/exclude / ssh://xxxx

Log trace below:

Registering (mktemp) temporary file
/tmp/duplicity-PY9oOo-tempdir/mktemp-esDT5F-6
AsyncScheduler: running task synchronously (asynchronicity disabled)
No handlers could be found for logger "paramiko.transport"
sftp put of /tmp/duplicity-PY9oOo-tempdir/mktemp-esDT5F-6 (as
duplicity-full.20130208T081130Z.vol45.difftar.gz) failed: Server
connection dropped:  (Try 1 of 5) Will retry in 10 seconds.
sftp put of /tmp/duplicity-PY9oOo-tempdir/mktemp-esDT5F-6 (as
duplicity-full.20130208T081130Z.vol45.difftar.gz) failed:  (Try 2 of
5) Will retry in 10 seconds.
sftp put of /tmp/duplicity-PY9oOo-tempdir/mktemp-esDT5F-6 (as
duplicity-full.20130208T081130Z.vol45.difftar.gz) failed:  (Try 3 of
5) Will retry in 10 seconds.
sftp put of /tmp/duplicity-PY9oOo-tempdir/mktemp-esDT5F-6 (as
duplicity-full.20130208T081130Z.vol45.difftar.gz) failed:  (Try 4 of
5) Will retry in 10 seconds.
sftp put of /tmp/duplicity-PY9oOo-tempdir/mktemp-esDT5F-6 (as
duplicity-full.20130208T081130Z.vol45.difftar.gz) failed:  (Try 5 of
5) Will retry in 10 seconds.
Removing still remembered temporary file
/tmp/duplicity-PY9oOo-tempdir/mktemp-esDT5F-6

Thank you!

--
Mikko Ohtamaa
http://opensourcehacker.com
http://twitter.com/moo9000