[X2go-dev] remote proxy closed the connection

[Gerry Reno]

On 02/04/2011 06:01 PM, Gerry Reno wrote:
> On 02/04/2011 04:43 PM, Mike Gabriel wrote:
>   
>> Hi Gerry,
>>
>> On Fr 04 Feb 2011 22:14:28 CET Gerry Reno wrote:
>>
>>     
>>> Has anyone found out how to prevent this "remote proxy closed the
>>> connection" error from happening when a session becomes detached and a
>>> user tries to resume the session?
>>>
>>> We are seeing this problem quite often and every once in a while you can
>>> get it to resume but mostly this session is unrecoverable and must be
>>> manually terminated - which is creating much sysadmin work.
>>>       
>> Test the following:
>>
>> Whenever this error occurs, restart your X2go server's SSH daemon. My
>> guess is that you can resume the session once SSH is restarted.
>>
>> I have read about weird port forwarding habits of the SSH daemon... I
>> also meet these problems with PyHoca-GUI.
>>
>> Greets,
>> Mike
>>
>>     
> Ok, the plot thickens.
>
> I took a look at netstat both prior-to and after we get this error:
>
> # normal state
> # we can successfully resume a session
>
>     # netstat -a | grep 300
>     tcp        0      0 localhost:30008         *:*                    
>     LISTEN    
>     tcp        0      0 localhost:30009         *:*                    
>     LISTEN    
>     tcp6       0      0 ip6-localhost:30008     [::]:*                 
>     LISTEN    
>     tcp6       0      0 ip6-localhost:30009     [::]:*                 
>     LISTEN    
>
>
> # # after I forced a session to detach
>
>     # netstat -a | grep 300
>     tcp        0      0 localhost:30008         *:*                    
>     LISTEN    
>     tcp        0      0 localhost:30009         *:*                    
>     LISTEN    
>     tcp        0      0 localhost:33552         localhost:30037        
>     TIME_WAIT 
>     tcp6       0      0 ip6-localhost:30008     [::]:*                 
>     LISTEN    
>     tcp6       0      0 ip6-localhost:30009     [::]:*                 
>     LISTEN    
>
>
> # # if we just wait for a while then reattempt to resume the session it
> succeeds
>
>     # netstat -a | grep 300
>     tcp        0      0 localhost:30008         *:*                    
>     LISTEN    
>     tcp        0      0 localhost:30009         *:*                    
>     LISTEN    
>     tcp6       0      0 ip6-localhost:30008     [::]:*                 
>     LISTEN    
>     tcp6       0      0 ip6-localhost:30009     [::]:*                 
>     LISTEN    
>
>
> So whatever is causing this TIME_WAIT is what appears to have a role in
> the error.
>
>
> Regards,
> Gerry
>
>
>
>   
What's interesting is that it presents the menu and the process is shown
as "running" so then your "suspend" it and "resume" it and you still get
the "remote proxy closed the connection" error and NX proxy shows
"aborting" but it does resume the session.  Very confusing to users but
at least they get their session back.


Regards,
Gerry