Re: [Duplicity-talk] duplicity stalling intermittently

On Mon, Mar 10, 2008 at 4:16 PM, Peter Schuller <address@hidden> wrote:

> Has anybody else seen anything like this? Or can anybody suggest where to
> look to find the problem? I'm running the latest duplicity version and have
> ample space on /tmp and (I think) no network problems so I'm not sure where
> to look next.

The "Stalled for too long, aborted copy" is coming from the duplicity backend
(rather than scp directly). It happens when the backend has detected that scp
has claimed itself to be "stalled" for a certain amount of time.

Unless there is a bug, it should only enter the "stalled" state as a result of
scp actually outputting the word "stalled".

So, the first place I would look is to figure out what is going on with the
scp session itself. First off, if you are able to 'catch it in the act' you
can try manually copying the file to see if you can trigger it. Or if not
just randombly grab a file of the same size as the duplicity volume size, and
copy it a few times spread over time to see if you can trigger it that way.
That is, if you want to be sure whether it can be triggered outside of
duplicity.

Yes, it can. I copied a large file using scp:

scp -v -o ServerAliveInterval=3 -o ServerAliveCountMax=1 file1 address@hidden:

and after copying part of the file it stalled with the following output:

debug1: Authentication succeeded (publickey).
debug1: channel 0: new [client-session]
debug1: Entering interactive session.
debug1: Sending environment.
debug1: Sending env LANG = en_US.UTF-8
debug1: Sending command: scp -v -t .
Sending file modes: C0644 74348520 file1
Sink: C0644 74348520 file1
file1 11% 8480KB 66.3KB/s - stalled -Disconnecting: Timeout, server not responding.
lost connection

This seems to happen quite regularly, but I still had to copy it 5 or 6 times before it failed. So I guess this is no longer really a duplicity problem, but I would still appreciate any suggestions if you have them.

Thanks,

Ed.

From:	Edward Chadwick
Subject:	Re: [Duplicity-talk] duplicity stalling intermittently
Date:	Tue, 11 Mar 2008 15:00:11 -0400