ssh-keyscan - is a utility for gathering the public SSH host keys of a number of hosts

To read all public keys from the host

$ ssh-keyscan 192.168.122.50

To read all public keys from the host at port number 22

$ ssh-keyscan -p 22 192.168.122.50

To read all public keys of the rsa type

$ ssh-keyscan -t rsa 192.168.122.50

To update the known_hosts file located in the path, ~/.ssh/known_hosts

$ ssh-keyscan -H 192.168.122.50 >> ~/.ssh/known_hosts

regards,

T.Dhanasekar