Log on to your server as su and create the message text you want to show
vi /etc/ssh/warning.txt
Now, create your message by pressing “i” to enter text insert mode, press “esc” when you are done.
####################################### # # # Warning - Private SSH Server # # Please leave immediately # # # #######################################
Press :w to save and :q to quit vi
Edit the main ssh config file and let it know that you are using a banner
# vi /etc/ssh/sshd_config
Search for the word banner and change the line from
#Banner /some/path
to
Banner /etc/ssh/warning.txt
Now restart ssh
# /etc/init.d/sshd restart
Login to your server and see the new message
You can do exactly the same to display a message after the user logs in by editing the file /etc/motd
vi /etc/motd
This file is read by CentOS every time a user starts a shell session so no restart or ssh config is required.
