ssh_exchange_identification: Connection closed by remote host
When using SSH this error may show it's ugly head on occasion. Many searches for the issues point to funny TCP connection tweaks or that sshd needs to be re-configured. This is not the case.
Symptoms
Connecting to SSH servers gives this message:
$ ssh atom@example.com ssh_exchange_identification: Connection closed by remote host
Or maybe this if using verbose mode.
$ ssh -v atom@example.com OpenSSH_4.7p1, OpenSSL 0.9.8g 19 Oct 2007 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to example.com [10.65.0.2] port 22. debug1: Connection established. debug1: identity file /home/atom/.ssh/identity type -1 debug1: identity file /home/atom/.ssh/id_rsa type 1 debug1: identity file /home/atom/.ssh/id_dsa type -1 ssh_exchange_identification: Connection closed by remote host
Try re-learning the host identity first after seeing the above message message:
$ cd ~/.ssh/ $ mv known_hosts known_hosts.tmp
When you re-connect you will be prompted to accept the host identity again.