1. Edit the Banner message
sudo nano /etc/issue.net
Sample text:
Authorized access only. Unauthorized use is prohibited and may be monitored.
2. Configure SSH to use the Banner
sudo nano /etc/ssh/sshd_config
Ensure “Banner /etc/issue.net”
Then restart SSH
sudo systemctl restart ssh
This banner will now show before SSH login prompts
3. Post-login Message
Use MOTD (Message of the Day) to display info after login
sudo nano /etc/motd
Example Banner Text:
NOTICE: This system is for authorized users only. Activity may be monitored and reported to security personnel. Disconnect immediately if you are not an authorized user.