ssh problem ssh_exchange_identification

[Rudy Gevaert <rudy@zeus.rug.ac.be>]

Hi,

I was busy closing ports on my server this week, and nmap shows the
following ports are still open:

schamper:/home/rudy# nmap -sS kain.rug.ac.be

Starting nmap V. 2.54BETA31 ( www.insecure.org/nmap/ )
Interesting ports on kain.rug.ac.be (157.193.88.9):
(The 1552 ports scanned but not shown below are in state: closed)
Port       State       Service
22/tcp     open        ssh
25/tcp     open        smtp

That I wanted.

I also made hosts.allow and deny empty.

When I try to ssh into my box I get:
rudy@schamper:~$ ssh rudy@kain.rug.ac.be -v
OpenSSH_3.4p1 Debian 1:3.4p1-1, SSH protocols 1.5/2.0, OpenSSL
0x0090603f
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Rhosts Authentication disabled, originating port will not be
trusted.
debug1: ssh_connect: needpriv 0
debug1: Connecting to kain.rug.ac.be [157.193.88.9] port 22.
debug1: Connection established.
debug1: identity file /home/rudy/.ssh/identity type 0
debug1: identity file /home/rudy/.ssh/id_rsa type -1
debug1: identity file /home/rudy/.ssh/id_dsa type -1
ssh_exchange_identification: Connection closed by remote host
debug1: Calling cleanup 0x8063a9c(0x0)
rudy@schamper:~$


What could this be?  I can't remember if I logged in after I adjusted
the hosts.allow file.

I don't have fysical access to the box now, but I would like to know
what I should check when I have next monday.

Thanks in advance,
-- 
Rudy Gevaert                rudy@gnu.org rudy@zeus.rug.ac.be
Web page                    http://www.webworm.org
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