Information
The Banner parameter specifies a file whose contents must be sent to the remote user before authentication is permitted. By default, no banner is displayed.
Rationale:
Banners are used to warn connecting users of the particular site's policy regarding connection. Consult with your legal department for the appropriate warning banner for your site.
Solution
Edit the /etc/ssh/sshd_config file to set the parameter as follows:
Banner /etc/issue.net
Default Value:
OS Default: No