I have just migrated from using a Solaris box as my work system to having Fedora Core 6 on my desktop PC. I have a number of ssh 'pinholes' in the company firewall to let me connect to external systems. These are to four external systems and from the Solaris system they all work still. From the new FC6 system they all work *except* for the one to my home system. Thus the basics of ssh security etc. would seem to be OK. The one that doesn't work is as follows:- ssh client - Fedora core 6, OpenSSH_4.3p2 sshd host - Slackware 11, OpenSSH_4.4p1 With -vvv on the client I see:- OpenSSH_4.3p2, OpenSSL 0.9.8b 04 May 2006 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug2: ssh_connect: needpriv 0 debug1: Connecting to home.isbd.net [84.45.228.40] port 22. debug1: Connection established. debug1: identity file /home/chris/.ssh/identity type 0 debug3: Not a RSA1 key file /home/chris/.ssh/id_rsa. debug2: key_type_from_name: unknown key type '-----BEGIN' debug3: key_read: missing keytype debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug2: key_type_from_name: unknown key type '-----END' debug3: key_read: missing keytype debug1: identity file /home/chris/.ssh/id_rsa type 1 debug3: Not a RSA1 key file /home/chris/.ssh/id_dsa. debug2: key_type_from_name: unknown key type '-----BEGIN' debug3: key_read: missing keytype debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug3: key_read: missing whitespace debug2: key_type_from_name: unknown key type '-----END' debug3: key_read: missing keytype debug1: identity file /home/chris/.ssh/id_dsa type 2 debug1: Remote protocol version 1.99, remote software version OpenSSH_4.4 debug1: match: OpenSSH_4.4 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_4.3 debug2: fd 3 setting O_NONBLOCK debug1: SSH2_MSG_KEXINIT sent and then after a long wait it times out with:- read from socket failed: Connection reset by peer A Google search has turned up one suggestion that it might be to do with MTU and fragmentation but I have tried setting the MTU to 576 at both ends and it still acts exactly the same. Other Linux boxes at the client end do work (one older Fedora, I think and one kubuntu) although another Fedora Core 6 installation fails in exactly the same way for this one host. So it does rather look as if it might be a Fedora Core 6 specific problem. Can anyone suggest any reason for this problem and how to fix it? I'm stumped. -- Chris Green