I'm having a really annoying problem on my Ubuntu laptop. I noticed it today, after upgrading to Ubuntu 11.04, although I'm not entirely sure this is the cause as I played with my ssh keys a few days ago. The problem is, whenever I try to ssh to ANY host I get the following error: Read from socket failed: Connection reset by peer running with -vvv gives the following output: OpenSSH_5.8p1 Debian-1ubuntu3, OpenSSL 0.9.8o 01 Jun 2010 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug2: ssh_connect: needpriv 0 debug1: Connecting to hostname [10.0.0.2] port 22. debug1: Connection established. debug1: permanently_set_uid: 0/0 debug1: identity file /root/.ssh/id_rsa type -1 debug1: identity file /root/.ssh/id_rsa-cert type -1 debug1: identity file /root/.ssh/id_dsa type -1 debug1: identity file /root/.ssh/id_dsa-cert type -1 debug1: identity file /root/.ssh/id_ecdsa type -1 debug1: identity file /root/.ssh/id_ecdsa-cert type -1 debug1: Remote protocol version 1.99, remote software version OpenSSH_4.2 debug1: match: OpenSSH_4.2 pat OpenSSH_4* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.8p1 Debian-1ubuntu3 debug2: fd 3 setting O_NONBLOCK debug3: load_hostkeys: loading entries for host "hostname" from file "/root/.ssh/known_hosts" debug3: load_hostkeys: loaded 0 keys debug1: SSH2_MSG_KEXINIT sent Read from socket failed: Connection reset by peer My /etc/ssh/ssh_config: Host * SendEnv LANG LC_* HashKnownHosts yes GSSAPIAuthentication no GSSAPIDelegateCredentials no I can connect to my laptop from any other server via ssh, and I can also ssh localhost from my laptop successfully. I can connect to all these other server from other laptops, and I don't see anything in the logs of the other servers regarding my failed attempt. I tried to stop iptables, didn't help. I tried several tricks I could find online with my /etc/ssh/ssh_config, but I was unsuccessful in solving the problem... Any ideas? Edit: This is the log from one of the hosts I try to connect to: May 1 19:15:23 localhost sshd[2845]: debug1: Forked child 2847. May 1 19:15:23 localhost sshd[2845]: debug3: send_rexec_state: entering fd = 8 config len 577 May 1 19:15:23 localhost sshd[2845]: debug3: ssh_msg_send: type 0 May 1 19:15:23 localhost sshd[2845]: debug3: send_rexec_state: done May 1 19:15:23 localhost sshd[2847]: debug1: rexec start in 5 out 5 newsock 5 pipe 7 sock 8 May 1 19:15:23 localhost sshd[2847]: debug1: inetd sockets after dupping: 3, 3 May 1 19:15:23 localhost sshd[2847]: Connection from 10.0.0.7 port 55747 May 1 19:15:23 localhost sshd[2847]: debug1: Client protocol version 2.0; client software version OpenSSH_5.8p1 Debian-1ubuntu3 May 1 19:15:23 localhost sshd[2847]: debug1: match: OpenSSH_5.8p1 Debian-1ubuntu3 pat OpenSSH* May 1 19:15:23 localhost sshd[2847]: debug1: Enabling compatibility mode for protocol 2.0 May 1 19:15:23 localhost sshd[2847]: debug1: Local version string SSH-2.0-OpenSSH_5.3 May 1 19:15:23 localhost sshd[2847]: debug2: fd 3 setting O_NONBLOCK May 1 19:15:23 localhost sshd[2847]: debug2: Network child is on pid 2848 May 1 19:15:23 localhost sshd[2847]: debug3: preauth child monitor started May 1 19:15:23 localhost sshd[2847]: debug3: mm_request_receive entering May 1 19:15:23 localhost sshd[2848]: debug3: privsep user:group 74:74 May 1 19:15:23 localhost sshd[2848]: debug1: permanently_set_uid: 74/74 May 1 19:15:23 localhost sshd[2848]: debug1: list_hostkey_types: ssh-rsa,ssh-dss May 1 19:15:23 localhost sshd[2848]: debug1: SSH2_MSG_KEXINIT sent May 1 19:15:23 localhost sshd[2848]: debug3: Wrote 784 bytes for a total of 805 May 1 19:15:23 localhost sshd[2848]: fatal: Read from socket failed: Connection reset by peer