It is possible to configure logon or welcome banner in the SSH server with the use of the Banner directive in /etc/ssh/sshd_config file.The Banner directive is only available for SSH protocol version 2 and by default there are no banner configured.
1. Create a banner file.
First you need to create the file that will include your banner for your users. In Debian, the default banner is located in /etc/issue.net file
nano /etc/issue.net
You can put here anything you want or just a welcome message like this:
###############################################################
Welcome to my server!
Disconnect IMMEDIATELY if you are not an authorized user!
###############################################################
2. Configure the /etc/ssh/sshd_config file
Now, add or remove the # from the beginning of the line Banner /etc/issue.net from /etc/ssh/sshd_config file.
nano /etc/ssh/sshd_config
Banner /etc/issue.net
Restart sshd daemon for the changes to take effect Continue Reading…