ssh: The authenticity of host 'hostname' c

Question

When i ssh to a machine, sometime i get this error warning and it prompts to say "yes" or "no". This cause some trouble when running from scripts that automatically ssh to other machines.

Warning Message:

The authenticity of host '<host>' can't be established.
ECDSA key fingerprint is    SHA256:TER0dEslggzS/BROmiE/s70WqcYy6bk52fs+MLTIptM.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'pc' (ECDSA) to the list of known hosts.

Is there a way to automatically say "yes" or ignore this?

Answer 1

To disable (or control disabling), add the following lines to the beginning of /etc/ssh/ssh_config...

Host 192.168.0.*
   StrictHostKeyChecking=no
   UserKnownHostsFile=/dev/null

Options:

• The Host subnet can be * to allow unrestricted access to all IPs.
• Edit /etc/ssh/ssh_config for global configuration or ~/.ssh/config for user-specific configuration.

See http://linuxcommando.blogspot.com/2008/10/how-to-disable-ssh-host-key-checking.html

Similar question on superuser.com - see https://superuser.com/a/628801/55163