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