[X2Go-User] session resuming after disconnect/reconnect

[richter at ecos.de]

Hi,

I will debug this further when I have a some spare time.

Is there any documentation that describes how this port forwarding and ssh stuff works?

Gerald

> -----Original Message-----
> From: Mike Gabriel [mailto:mike.gabriel at das-netzwerkteam.de]
> Sent: Wednesday, October 24, 2012 10:22 AM
> To: Gerald Richter - ECOS
> Cc: x2go-user at lists.berlios.de
> Subject: Re: [X2Go-User] session resuming after disconnect/reconnect
> 
> Hi Gerald,
> 
> On Mi 24 Okt 2012 07:03:36 CEST  wrote:
> 
> > when a session gets disconnected (e.g. network connection is lost,
> > computer is powered down, without disconnect) I cannot simply resume
> > the session after the next connect.
> 
> Yes, this is a known issue with SSH and port forwarding. As X2Go media is
> transported over SSH port forwarding connections all parts of a session
> (graphics, audio, sshfs) are affected by disrupted connections that do not
> properly close open SSH port forwarding requests.
> 
> > I have first to pause the session, that wait a long time (don't know
> > exactly how long, but needs to be more than 30-60 seconds) and than I
> > am able to resume the session.
> 
> Yes, this exactly describes the phenomen. I have tried to catch these
> situations in Python X2Go code, but these precautions only work on some
> occasions.
> 
> > If I simply pause/resume the session or try to take it over, the
> > operation fails and the session is closed.
> >
> > Looks like after the pause of the old session, something does not get
> > terminated correctly and needs to timeout before I can resume the
> > session.
> >
> > Simply pausing/resuming a session works without problems, as long as
> > the ssh session isn't closed in between. It also works if I pause the
> > session, than disconnect the ssh connection. Than I can resume after I
> > have reconnected to the server.
> 
> What also works is restarting the SSH daemon on the server side.
> 
> Unfortunately, I cannot give more of a solution to this. If you find any ways to
> tweak the ssh daemon then we could put that into a README for Python
> X2Go (or into the wiki of X2Go).
> 
> Thanks,
> Mike
> 
> --
> 
> DAS-NETZWERKTEAM
> mike gabriel, rothenstein 5, 24214 neudorf-bornstein
> fon: +49 (1520) 1976 148
> 
> GnuPG Key ID 0x25771B31
> mail: mike.gabriel at das-netzwerkteam.de, http://das-netzwerkteam.de
> 
> freeBusy:
> https://mail.das-netzwerkteam.de/freebusy/m.gabriel%40das-
> netzwerkteam.de.xfb