Thanks Andy. It may be something in the network which is causing VNC to freeze, however if that is the case then VNC appears to be causing the network problem. My rationale is that the freeze mostly happens immediately after I bring the VNC window to the foreground. Also, the if I set a ping going on the SSH terminal session, it keeps going without problem during and after the freeze.
Either way, your suggestion of getting debug info from SSH is a good one - I'll report back when I've got some info from that. mark. On 6/8/05, Andy Bruce - softwareAB <[EMAIL PROTECTED]> wrote: > I think you are confusing SSH timeouts (which I get sporadically myself > when connecting to my business LAN) with the VNC freeze. In my > experience, the VNC freeze only occurs when the underlying network > connection itself hangs. Although it may appear that the problem is > VNC-related (since you can start another session presumably without > restarting your SSH tunnelling client), the symptom you report happens > only when there is a problem with the underlying network connection. VNC > is simply the innocent consumer of that connection. > > As far as I know, the only solution to your problem is to work thru the > SSH connectivity problems. I have one Windows-based client company who > has allowed the single port 22 to be opened (specifically for my use in > fact) since they do not wish to give me corporate VPN access. As I > mentioned above, that particular connection times out, freezes up, and > does other strange things which their "normal" VPN connection does not > do. You're in luck since you appear to have some control over your > connection to the remote Linux box; I suggest that you turn on debugging > on the SSH daemon on that box to get detailed information about what's > going on. In my case, the network folks (all M$NE certified, and > therefore useless for any real work) simply shrug their shoulders and > brush me off. > > Good luck, > > Andy > > Mark wrote: > > >I have been having problems with sessions hanging when running VNC > >over SSH. I will have a session open, and after some time find that > >the screen has frozen. Refreshing the screen doesn't help, however if > >I close the session I can open another one just fine (though it seems > >to take a few seconds longer to reconnect than it did originally). > >This happens in the following circumstances: > > > >* if I minimize the VNC session window for about 15 or more minutes, > >the session always freezes immediately after I maximize (I have a > >batch file printing the time continually and the time is current when > >I maximise, but does not continue to update). If I minimise and then > >maximise after a couple of minutes, the session does not freeze. If I > >maximise between 2 and 15 minutes the session sometimes freezes > >(almost always after 5 minutes). > >* if the session is not minimised but just in the background, the > >session usually freezes but after a more variable and longer length of > >time. > >* sometimes the session freezes when I am using it actively. Again, > >length of time is variable. > > > >The setup I am using is as follows: > > > >VNC Client (RealVNC Free 4.1.1) on Win XP Pro > >| > >Linux firewall running NAT > >| > >ADSL Router running NAT > >| > >| > >ADSL Router running NAT > >| > >Linux Firewall running NAT & OpenSSHd > >| > >Remote machine (RealVNC Free 4.1.1 server) on Win XP Pro > >-session timeout set to 60000 seconds > > > >The only port open on the remote Linux firewall is 22, and I set up a > >SSH tunnel from local client (with PuTTY) to the remote Linux > >Firewall, which then forwards VNC traffic to the remote VNC server. > > > >I don't see any problem with the SSH session when the VNC session > >hangs (nothing in the SSH log, SSH terminal session is fine). I have > >also reproduced the problem connecting from different PCs. > > > >I do get an entry in the Windows event log of the VNC server > >(connection reset by peer 10054), but this entry is logged after the > >time session froze, so presumably it is a result of the freeze not the > >cause? > > > >If I put the remote machine in front of the Linux firewall (ie just in > >ADSL router NAT) and connect directly (ie no SSH tunnel) the > >connection is stable and does not hang. > > > >Any assistance in fixing this would be most appreciated. > > > >thanks > > > >mark. > >_______________________________________________ > >VNC-List mailing list > >VNC-List@realvnc.com > >To remove yourself from the list visit: > >http://www.realvnc.com/mailman/listinfo/vnc-list _______________________________________________ VNC-List mailing list VNC-List@realvnc.com To remove yourself from the list visit: http://www.realvnc.com/mailman/listinfo/vnc-list
