[FreeNX-kNX] nxagent session gets lost, user gets new session even though one already exists

[Mario Becroft]

"Marcelo Boveto Shima" <marceloshima at gmail.com> writes:

> This happens with Windows XP too. But I don´t use Windows often,
> so it is not a problem for me.
> I will take a look at this problem this weekend.

That's interesting. I did some more work on this today, mainly just
trying to repeat the problem. So I got the user's laptop for half an
hour and played with suspending it while nxclient was running. One thing
I noted is that this user's connection is forwarded to to the nx host
from a gateway machine via xinetd. This might have some influence on the
problem (most obviously, it may mean that the ssh connection to the nx
host remains alive even after the laptop has been suspended, and it may
not get reset once the laptop comes up again.)

I also noticed that when I tried to repeat the problem, it is slightly
different from what I first thought. Below is an exact sequence of events
that is 100% repeatable.

I may work on this on the weekend too--let's share notes if we find out
anything interesting.

--8<---------------cut here---------------start------------->8---
user is logged in. there is some periodic activity on-screen (don't
know if this is important)

suspend laptop, wait anywhere from 1 minute to half an hour. Note: at
this stage the nxserver.log shows "display failure detected" fairly
quickly.

resume laptop. his nxclient says the connection with remote server was
shut down.

note that all this time, user has shown as still logged in from the
gateway host on nxserver --list. You can wait any length of time at this
stage (at least 5 minutes), and he is still listed as logged in.

login again. During and after the login process, note that user is no
longer listed at all under nxserver --list. his session resumes
apparently fine.

suspend the session. It is still not listed in nxserver --list.

Now login again. Instead of resuming, he gets a new session (because his
session was not listed and so his client did not even try to resume it).
The new session is now listed as normal in nxserver --list
--8<---------------cut here---------------end--------------->8---

-- 
Mario Becroft <mb at gem.win.co.nz>