[ILUG] How do I make the first ssh connection?

[Conor Daly]

Hi,

I've opened ports 21, 22, 23 and 80 in my firewall and forwarded them to
port 22 on an internal host.  I all cases, ssh to the firewall from *inside*
the firewall gets forwarded to the ssh server and I get to connect but from
*outside*, it's a different matter.  The outside machine I'm going from is 
itself masqued and has yet to make a first connection with ssh (I presume
that's something to do with physically bringing public key(s) to the server
and installing them somewhere.  Anyone able to help me there?).  I had port
80 forwarded to an internal port 80 and that worked so I'm tunnelling
through the firewall that way anyhow but I'm unable to connect with ssh.  

I tested my port forwarding and firewall config with an online port scanner 
and got hits at both the firewall and at the ssh server so I'm at something 
of a loss.  
There was mention on the masq list of dynamic IP addresses causing problems 
but I haven't even got to the stage of being asked about an unknown host.

I've brought keys back and forth and put them in places like
/etc/known_hosts and $HOME/.ssh/authorized_keys and so on.

Can anyone suggest anything?

Session transcripts follow.

[cdaly at bofh .ssh]$ ssh -v -p 21 xxx.xxx.xxx.xxx
SSH Version OpenSSH_2.1.1, protocol versions 1.5/2.0.
Compiled with SSL (0x0090581f).
debug: Reading configuration data /etc/ssh/ssh_config
debug: Applying options for *
debug: Seeding random number generator
debug: ssh_connect: getuid 500 geteuid 0 anon 0
debug: Connecting to xxx.xxx.xxx.xxx [xxx.xxx.xxx.xxx] port 21.
debug: Allocated local port 1021.
debug: Connection established.
debug: Remote protocol version 1.99, remote software version OpenSSH_2.1.1
Enabling compatibility mode for protocol 2.0
debug: Local version string SSH-2.0-OpenSSH_2.1.1
debug: Seeding random number generator
debug: send KEXINIT
debug: done
debug: wait KEXINIT
 35 30 30 20 63 6f 6d 6d
Disconnecting: Bad packet length 892350496.
debug: Calling cleanup 0x805db00(0x0)

In the logs on the server side I just get 

Apr 23 14:01:10 Valkerie sshd[2679]: Connection from yyy.yyy.yyy.yyy port 8120
Apr 23 14:01:10 Valkerie sshd[2679]: Did not receive ident string from yyy.yyy.yyy.yyy

TIA

Conor
-- 
Conor Daly <conor.daly at oceanfree.net>

Domestic Sysadmin :-)
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