You can configure a banner message to appear at the beginning of a Telnet session to a storage system.
You configure a banner message to appear at the beginning of a Telnet session to a storage system by creating a file called issue in the /etc directory of the administration host’s root volume. The message only appears at the beginning of the session. It is not repeated if there are multiple failures when attempting to log in.
The following example shows how the message in /etc/issue appears, assuming that the contents of the issue file is "This system is for demonstrations only".
admin_host% telnet mysystem Trying 192.0.2.132... Connected to mysystem.xyz.com Escape character is ‘^]’. This system is for demonstrations only. Data ONTAP <mysystem.xyz.com> Login: