Thanks Wez, Logs from VNCviewer don't to indicate (to me) anything untoward. I tested as follows:
(1) open SSH/VNC session and close it before the screen freeze (ie a 'good' session) (2) open SSH/VNC session, minimize it, wait for 10-15 minutes, unminimize to freeze the session (ie a 'bad' session). I then left the window open until VNC closed itself (usually after a couple of minutes). FYI, letting it close this way as caused the SSH tunnel to close ungracefully (according to SSH logs which gave message read<=0 rfd 10 len -1 & read failed) as opposed to closing the window manually which caused the SSH tunnel to close normally (close initiated with rcvd close message). I compared the vncviewer logs and found: (1) nothing reported in the log of the bad session immiediately before I unminimised (only entries were from before when I minimized) (2) nothing reported in the log after I unminimised the session (3) after VNC closed itself, very little difference in the log output between the good and the bad sessions. I've attached the last few lines of each in case they mean anything to you. Is there a more verbose debugging mode? Any suggestions as to how I can get logging working for vncserver? Thanks mark. --------------------------------------------------- Last lines of 'good' session log: DesktopWindow: WM_CLOSE 90746 CConn: window closed DesktopWindow: null _this in 90746, message 2 DesktopWindow: null _this in 90746, message 130 DesktopWindow: ~DesktopWindow LowLevelKeyEvents: disable 00090746 DesktopWindow: ~DesktopWindow done Clipboard: removing c0772 from chain (next is 3e067c) MsgWindow: null _this in c0772, message 2 MsgWindow: null _this in c0772, message 82 MsgWindow: destroyed window "Clipboard" (c0772) Threading: stopped CConnThread(3a58a0) main: quitting viewer Threading: stopped RegConfigThread(13f978) Threading: destroying CConnThread(3a58a0) Threading: destroyed CConnThread(3a58a0) Threading: joining RegConfigThread(13f978) Threading: joined RegConfigThread(13f978) Registry: RegCloseKey(7ac) Threading: destroying RegConfigThread(13f978) Threading: already joined RegConfigThread(13f978) Threading: destroyed RegConfigThread(13f978) --------------------------------------------------------------------------- Last lines of 'bad' session log (entries immediately before these lines were timestamped 10 minutes before these lines): DesktopWindow: ~DesktopWindow LowLevelKeyEvents: disable 0024079C DesktopWindow: null _this in 24079c, message 2 DesktopWindow: null _this in 24079c, message 130 DesktopWindow: ~DesktopWindow done Clipboard: removing 5bd07f8 from chain (next is 3e067c) MsgWindow: null _this in 5bd07f8, message 2 MsgWindow: null _this in 5bd07f8, message 82 MsgWindow: destroyed window "Clipboard" (5bd07f8) Threading: stopped CConnThread(3a58a0) Threading: destroying CConnThread(3a58a0) Threading: destroyed CConnThread(3a58a0) main: quitting viewer Threading: stopped RegConfigThread(13f978) Threading: joining RegConfigThread(13f978) Threading: joined RegConfigThread(13f978) Registry: RegCloseKey(7ac) Threading: destroying RegConfigThread(13f978) Threading: already joined RegConfigThread(13f978) Threading: destroyed RegConfigThread(13f978) On 6/10/05, James Weatherall <[EMAIL PROTECTED]> wrote: > Mark, > > You can enable debug output from VNC Viewer either to a console window with: > > Vncviewer -console -log=*:stderr:100 > > Or to C:\temp\vncviewer4.log with: > > Vncviewer -log=*:file:100 > > (You'll need to ensure that C:\temp exists and is writable) > > Cheers, > > Wez @ RealVNC Ltd. > > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of Mark > > Sent: 09 June 2005 13:59 > > To: [email protected] > > Cc: [EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED] > > Subject: Re: Screen freezing in VNC4.1.1 over SSH > > > > Oops, must have hit reply rather than reply all to my last message... > > > > ---------- Forwarded message ---------- > > From: Mark <[EMAIL PROTECTED]> > > Date: Jun 8, 2005 6:40 PM > > Subject: Re: Screen freezing in VNC4.1.1 over SSH > > To: James Weatherall <[EMAIL PROTECTED]> > > > > > > Wez, > > > > Thanks - I'll try running vncserver in debug mode and see if that > > suggests anything. How do I get debugging turned on? I have added > > DebugLevel and DebugMode DWORD keys to HKLM\Software\RealVNC\WinVNC4 > > (12 and 2 decimal respectively) and rebooted the machine, but I can't > > find any winvnc.log file (and did a file search just to make sure). > > I've also tried on another machine with VNC server in user mode and > > can't get that working either (with 2, 4, or 6 in the DebugMode key). > > Sorry if I am missing something obvious. > > > > Re my comment on the timer: > > To help figure out what happens when I have a simple batch script > > running which loops endlessly and prints the time to a terminal > > window. When running it will just show the time scrolling up the > > terminal window endlessly. > > > > When I unminimize VNC the screen updates and time appears to scroll up > > for a very short time before the window freezes. In other words, had > > the session frozen while VNC was minimised I would expect to see the > > time that the session froze as some time before I unminimised. > > However, what I always see is that very brief update and the freezing > > with the time showing the current time when I unminimised - so it > > would appear that the act of unminimising is triggering something > > which causes the session to freeze. > > > > On 6/8/05, James Weatherall <[EMAIL PROTECTED]> wrote: > > > Mark, > > > > > > I'd recommend running VNC Viewer with full debugging > > enabled, to see if it > > > reports any useful information. > > > > > > Since you don't see the problem when using VNC without SSH, > > it does seem > > > likely that something is amiss with your SSH tunnels. > > > > > > I'm not sure I understand your timer comment, but it is > > often the case that > > > VNC Viewer will not detect that a connection has dropped > > when minimized, > > > until it is restored, since it doesn't request updates or > > send input events > > > to the server when minimized and those are how it detects > > dead links. > > > > > > Regards, > > > > > > Wez @ RealVNC Ltd. > > > > > > > > > > -----Original Message----- > > > > From: Mark [mailto:[EMAIL PROTECTED] > > > > Sent: 08 June 2005 17:26 > > > > To: Collins, Kevin (MindWorks) > > > > Cc: James Weatherall; Andy Bruce - softwareAB; > > [email protected] > > > > Subject: Re: Screen freezing in VNC4.1.1 over SSH > > > > > > > > Kevin - CPU time in vncviewer remains at zero while > > active and once > > > > frozen. CPU usage is very low all the time, only > > occasionally flicking > > > > up to 1 or 2 %, unless I move the VNC window around in > > which case it > > > > goes up, and then (eventually) CPU time does increment. > > > > > > > > While looking at this, VNC viewer quit (after session was frozen) > > > > without warning or error, and this did give SSH errors > > relating to a > > > > session unexpectedly closing, which makes sense. > > > > > > > > Wez - I don't think SSH timing out is causing the problem: > > > > * no errors in SSH log prior to VNC session freezing > > > > * session freezing is mostly triggered by my brining > > VNCviewer out of > > > > a minimised state (when I do this the timer I have > > running continues > > > > to update for <<1 second before freezing, so it would > > appear that all > > > > is OK with the session until I unminimize VNCviewer) > > > > * the VNC server error always happens about 30 after the freeze > > > > > > > > That said, I there is certainly something going on > > between VNC and SSH > > > > as I have never seen this if I run VNC in the clear. > > > > > > > > mark. > > > > > > > > On 6/8/05, Collins, Kevin (MindWorks) > > > > <[EMAIL PROTECTED]> wrote: > > > > > Wez, > > > > > > > > > > is it possible this is related to the "hang" (in > > actuality, > > > > > looping) that I have been working with you on? > > > > > > > > > > Mark - if you look at the Windows task manager, under the > > > > "Processes" > > > > > tab, is the vncviewer process "CPU Time" value incrementing? > > > > > > > > > > Kevin > > > > > > > > > > -----Original Message----- > > > > > From: [EMAIL PROTECTED] > > > > [mailto:[EMAIL PROTECTED] On > > > > > Behalf Of James Weatherall > > > > > Sent: Wednesday, June 08, 2005 7:24 AM > > > > > To: 'Mark'; 'Andy Bruce - softwareAB' > > > > > Cc: [email protected] > > > > > Subject: RE: Screen freezing in VNC4.1.1 over SSH > > > > > > > > > > > > > > > Mark, > > > > > > > > > > I think Andy is suggesting that the problem is SSH > > timing out the > > > > > tunnelled > > > > > connection - this theory is supported by the fact that the > > > > server sees > > > > > the > > > > > connection drop. > > > > > VNC clearly isn't causing any network problems, since > > you can still > > > > > interact > > > > > with the SSH session. > > > > > > > > > > Cheers, > > > > > > > > > > Wez @ RealVNC Ltd. > > > > > > > > > > > > > > > > -----Original Message----- > > > > > > From: [EMAIL PROTECTED] > > > > > > [mailto:[EMAIL PROTECTED] On Behalf Of Mark > > > > > > Sent: 08 June 2005 14:35 > > > > > > To: Andy Bruce - softwareAB > > > > > > Cc: [email protected] > > > > > > Subject: Re: Screen freezing in VNC4.1.1 over SSH > > > > > > > > > > > > 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 > > > > > > > >[email protected] > > > > > > > >To remove yourself from the list visit: > > > > > > > >http://www.realvnc.com/mailman/listinfo/vnc-list > > > > > > _______________________________________________ > > > > > > VNC-List mailing list > > > > > > [email protected] > > > > > > To remove yourself from the list visit: > > > > > > http://www.realvnc.com/mailman/listinfo/vnc-list > > > > > _______________________________________________ > > > > > VNC-List mailing list > > > > > [email protected] > > > > > To remove yourself from the list visit: > > > > > http://www.realvnc.com/mailman/listinfo/vnc-list > > _______________________________________________ > > VNC-List mailing list > > [email protected] > > To remove yourself from the list visit: > > http://www.realvnc.com/mailman/listinfo/vnc-list _______________________________________________ VNC-List mailing list [email protected] To remove yourself from the list visit: http://www.realvnc.com/mailman/listinfo/vnc-list
