To create a banner so that whenever a user logs into a system will see some default text, you can couple of options
1. put the default text into /etc/motd
2. type echo “<the text you want to display>” into /etc/profile
3. type echo “<the text you want to display>” into user home .profile file.
All the above cases will worf after successful login.
if you want to Display text before successful login
edit /etc/ssh/sshd_config
uncomment
Banner /etc/issue
#few others i use to imply
LoginGraceTime 60
MaxAuthTries 2
MaxAuthTriesLog 2