Odd tcp dump? was: ssh working with dialup, not through router

[M. Fioretti]

On Tue, May 18, 2004 22:53:16 PM +0200, shrek-m at gmx.de
(shrek-m at gmx.de) wrote:
> M. Fioretti wrote:
> 
> >still trying to track why ssh doesn't work anymore, see my original
> >posting.
> >
> 
> 1.
> firewall,
> ssh is really open ?
> 
Looks like it:

nmap -P0 -p 22 that.ip

Starting nmap V. 3.00 ( www.insecure.org/nmap/ )
Interesting ports on  (its.ip):
Port       State       Service
22/tcp     open        ssh                     

Nmap run completed -- 1 IP address (1 host up) scanned in 1 second

> 2.
> tcp_ecn - problem ?
> 
> # sysctl -a | grep ecn
> net.ipv4.tcp_ecn = 0
> 

Same result here

> The recommended solutions require to turn off ECN support
> 
> sysctl and /etc/sysctl.conf
> (Add net.ipv4.tcp_ecn = 0 to sysctl.conf)

This is not present in my /etc/sysctl.conf file. Do I only have to add
it to the end? And does it require reboot (I have other stuff running
here now)?

> 3.
> your router does not close the connection after 1 minute of inactivity or 
> similiar ?
> ping your_server while you try to ssh in

No difference. Still freezes at the same point, with the ping happily
going with times between 260 and 120 milliseconds.

Ciao,
	Marco F.

-- 
Marco Fioretti                 m.fioretti, at the server inwind.it
Red Hat for low memory         http://www.rule-project.org/en/

A good man is intelligent, and a bad man is also an idiot. Moral and
intellectual characteristics go together - Jorge Luis Borges