In Java every web application has its own session information and this session information is applicable only with in that web application only. The application server like JBoss, Weblogic etc. are responsible for managing session for the web application.
So What’s the big deal in ATG Session Management if session is managed by App Server??
As we know we can have multiple WAR files in ATG Ear. By default, J2EE servers hand out different session objects in each web application visited, even if all requests came from the same browser. But in ATG we have Session Scoped Components and each war should have accessed to same session components.
Sharing of Parent WAR Session ID
When multiple web applications exist in the ATG EAR file, one of them must be designated as the parent application. Being the parent means that that application’s session ID is used as the basis for creating the ATG session scope root.
atg_bootstrap.war is parent web application in ATG.
Your web applications should define the atg.session.parentContextName and atg.dafear.bootstrapContextName parameters in their web.xml to point to the parent web-application as shown:
<description>The name of the DAF bootstrap WAR context.</description>
The above configuration is required and applicable only for ATG Session Scoped Components not for the HTTP Session.