For Security reasons & Company Policies administrators would need to display a Warning Banner for SSH connections. Below would be a simple procedure to add a custom SSH-banner.
By default there would be no banner set & banner option would not be enabled. To enable it
– Edit /etc/ssh/sshd_config file (Use text editors vi or nano)
– uncomment Banner field & specify a path to the Banner file, like /etc/ssh/ssh-banner. Save and quit.
– Create a new file ssh-banner under /etc/ssh & add the custom SSH banner to be displayed.
– Restart SSH service. #service sshd restart
Once done, SSH connections will display the warning message.