EP: Portal – Sessions & POWL Locks
As we know the Enterprise Portal serves as the conduit channel through our organizational end-users gain access to business apps, information flow and data. From an end users perspective utilizing the enterprise Portal is a straightforward process. We simply logon, fulfill our work obligations and logoff. As an end user we are only concerned with the graphical representation of the Portal that we are delivered with through our monitors representation and we are not truly troubled by what underlying functionality is taking place.
If you have ever encountered a “User Session” or “Cookie Rentention” issue with the Portal then you are most likely familiar with the transaction of SM04.
- SM04: Essentially SM04 as a transaction provides us with a view on the different connection types. With reference to SM04 the connection type means what kind of user (and their connection) is connecting to the SAP System e.g. the Portal.
Although SAP NetWeaver Portal comes with an out-of-the-box mechanism that terminates a session when the user closes the browser or navigates out of the SAP iFrame, the mechanism does not handle logoff. Instead, your company portal must raise the terminating event when logging off from the SAP portal.
- RFC Connections remain in SM04: http://wiki.scn.sap.com/wiki/display/ABAPConn/RFC+Connections+remain+in+SM04
Portal Session Types
- Connection Types: Connection types include that of RFC, GUI, Plugin (HTTP/SMTP).
- RFC Connections: This particular connection type references users which are connected up to the system (Portal) via an RFC Connection. (See RFC’s using the SM04 transaction), a simplistic view on a RFC connection type user is someone who is utilizing the connection using external based RFC clients.
- GUI Connections: As the title implies this particular connection types makes referneces to users who utilize access to the Portal via a GUI based connection platform.
Another occurrence I commonly see tagged as a Portal based issue is the occurrence of POWL Locks when an application such as SRM (Shopping Cart) is being utilized.
Now from the perspective of the Enterprise Portal itself and session management the point of interest here relates to SM04 as oppossed to SM12 if POWL locks appear to be the central issue.
The documentation outlined in my previous response is the core resolution material towards avoiding POWL Locks and ensuring the application sessions close correctly.
How to avoid query locks using POWL Shadowing:
POWL – FAQ: http://wiki.scn.sap.com/wiki/display/WDABAP/FAQ+ABOUT+POWL
POWL Configurations: http://wiki.scn.sap.com/wiki/display/WDABAP/POWL+CONFIGURATIONS
Shadow Mode in POWL: http://wiki.scn.sap.com/wiki/display/WDABAP/Shadow+Mode+in+POWL
- SAP KBA: 1925854 – Changing the Shadowing Flag in 731 Basis release
- SAP KBA: 1625506 – POWL Query is locked – SRM
- SAP KBA: 1594585 – Query ‘XXX’ is already open in another session
- SAP Note: 1433603 – NWBC causes locks in WebDynpro * escpecially POWLs