I haven't seen this type of functionality, it will likely require a major customization to do such a requirement. Why is this needed specifically for Tableau, as opposed to anything accessible on the network? Perhaps can it go upstream when the user logs into their workstation?
Each website/web-app is required to have this banner to be acknowledged by the user before logging in.
>> Why is this needed specifically for Tableau, as opposed to anything accessible on the network?
It's specially needed for applications served via the web, because even though you're logged in to the network (which has its own banner) someone could conceivably say they agreed to the network monitoring but not the web/app. I wish that wasn't the case, but the short of it is... tableau needs this banner. If we aren't capable of providing this banner, we may not be allowed to have tableau on the network.
Thanks for the link Vien, it's good to know we could modify the log-in screen... unfortunately for us it probably won't work.
The proper solution would have to include "acknowledgement" by the user, meaning the warning/banner would display the message and the user would have to "click" on OK or PROCEED for concent. To make matter's worse we're using Common Access Card (CAC) for two factor authentication, so the log-in screen does not show up. The steps are, web-browser: https:\\tableauserver, it prompts for CAC (user enters PIN) and it goes straight to tableau (bypassing the log-in screen - the user never sees the log-in screen).
Have a look at openid and see if this will work for you. I believe the concept is that you have a front-end authentication app that handles all the agreement and signin, then the id is passed into Tableau Server.
As you can imagine, we're trying to keep the solution within the tableau server itself, but good to know tableau could communicate with an IDP that could provide the banner.
Are you guys using a reverse proxy at all? If you do, you may be able to configure the reverse proxy to have this prompt before redirecting into the tableau server. You also may be able to build this webpage directly on the Tableau server, have the reverse proxy to point to it, and then have it forward on to your tableau server page. You would likely need to point your tableau desktops directly to the server though.