The reference configuration deployment architecture supports portlet session failover, as described in Session State Availability. It does this by deploying Portal Server in an Application Server cluster that uses High Availability Session Store (HADB) to store and replicate portlet session state.
If your business solution does not involve portlets that store session state, then portlet session failover might not be a requirement for your portal service deployment. If that is the case, you do not need to deploy Portal Server in an Application Server cluster. However, if you have other reasons beside portlet session failover for deploying Portal Server in an Application Server cluster, you can use this guide, but omit the section on implementing portlet session failover.
Portal Server can be deployed in a web container provided by nonclustered Application Server instances. This approach would substantially change the implementation of the portal service module described in Chapter 6, Implementation Module 3: Portal Server With Portlet Session Failover on Application Server Cluster.
At the present time, however, an alternative implementation for Portal Server on Application Server (without portlet session failover) has not yet been documented.