Yes, you can configure banner. Here is an example from CLI on how to configure the banner:
Connect to the NodeGrid via ssh or console port, and log in as admin.
Then type the following commands:
[admin@nodegrid /]# cd /settings/system_preferences/
[admin@nodegrid system_preferences]# set enable_banner=yes banner="Warning:\\nThis session will be monitored for auditing purposes"
[+admin@nodegrid system_preferences]# commit
And here are the steps to configure the banner from the Web:
Log in as admin to the WebUI
Go to System, Preferences, and check the "Enable Banner Message" check box
Add this to the Banner box: Warning: This session will be monitored for auditing purposes
Save