Re: ssh tunnel delay

[Sean Alexandre <sean@alexan.org>]

On Tue, Sep 10, 2013 at 01:11:17PM +0200, Juan Sierra Pons wrote:
> Hi,
> 
> I don't see anything strange in the logs provided. Do you see anything
> strange in your dmesg, /var/log/daemon.log, etc?
> 
> Is the DNS on the server's side working properly? Sometimes when the
> reverse DNS is not properly configure some TCP based services get some
> delay on first connection: ssh, mysql, etc
> 
> Can a network issue  be discarded. Please check with mtr: mtr remote server
> 
> Not a solution but a very tiny improvement , launch the tunnel with the -C
> (compression) parameter.

Thanks for looking at this. The other things you list look fine. I did notice
something else with the log, though. Below I type the line "hello". Then
there's the 80 second delay. And then there's the log messages after the "hello":

debug1: Entering interactive session.
client> nc localhost 1110                                                
hello
debug1: Connection to port 1110 forwarding to localhost port 1212 requested.         
debug2: fd 6 setting TCP_NODELAY                                                     
debug2: fd 6 setting O_NONBLOCK                                                      
debug3: fd 6 is O_NONBLOCK                                                           
debug1: channel 2: new [direct-tcpip]                                                
debug2: channel 2: open confirm rwindow 2097152 rmax 32768

I think the delay no longer happens, with subsequent lines,  because
TCP_NODELAY and O_NONBLOCK get set. I wonder if there's a way to configure
things to set those from the start?