Starting and Stopping Portal Services 
Generally, it is necessary to restart a portal service if you change its configuration settings. Use SAP NetWeaver Administrator to start and stop services.
Note
For information about the effect of modifying service properties In a cluster environment, see Modifying Manager or Service Properties.
Open the SAP NetWeaver Administrator by either of the following methods:
Use the URL to your AS Java (hostname:port) to access the AS Java home page and use the link to SAP NetWeaver Administrator.
Alternatively, add nwa to the AS Java URL to access SAP NetWeaver Administrator directly. (hostname:port/nwa).
Go to and click the Start & Stop link.
The Start & Stop: Java EE Instances window opens.
Click the Java EE Application bar and select the relevant application in the Application List.
The Portal Services pane displays the services associated with the selected application.
Use the buttons Start Service or Stop Service.
For more information, see Starting and Stopping Java EE Applications.