Sessions
Ambari Web is a client-side JavaScript application, which calls the Ambari REST API (accessible from the Ambari Server) to access cluster information and perform cluster operations. After authenticating to Ambari Web, the application authenticates to the Ambari Server. Communication between the browser and server occurs asynchronously via the REST API.
Ambari Web sessions do not time out. The Ambari Server application constantly accesses the Ambari REST API, which resets the session timeout. During any period of Ambari Web inactivity, the Ambari Web user interface (UI) refreshes automatically. You must explicitly sign out of the Ambari Web UI to destroy the Ambari session with the server.
![](figures/1/figures/signout_lo.png)