Saturday, August 23, 2014

OAM 11gR2/Weblogic : The important of parameters in mod_wl_ohs.conf(Web Server plugins)

Configurations of various parameters in web server plugins plays in a major part in ensuring that Single-Sign-On works fine using OAM.

Oracle Documentation -

This post is intended to share my experiences with certain parameters and the repercussions if you don't include them :)

WLProxySSl works great if webserver is doing the SSL work. But if SSL being terminated by a load balancer then mod_wl will remove any incoming WL-Proxy-SSL and the request will reach OHS over HTTP this means that the WebLogic server won't ever get that header and so request.isSecure() will always return false. If you add that directive and set it to ON then the WebLogic plug-in will not remove any incoming WL-Proxy-SSL header. This lets WebLogic Server know that the original request was initiated over SSL.  WL-Proxy-SSL header should not be sent if the inbound traffic to the load balancer was not SSL (HTTPS).

Error Scenario

Once I added this parameter for under the <if weblogic_module> tag and set it to true, this issue no longer reccurred .

If you change the name of the WebLogic Server session cookie in the WebLogic Server Web application, you need to change the WLCookieName parameter in the plug-in to the same value. The name of the WebLogic session cookie is set in the WebLogic-specific deployment descriptor, in the <session-descriptor> element.

Error Scenario :
The Webcenter Portal application I was implementing SSO using OAM for, had changed the weblogic session cookie name to a non-JSESSION ID value for some reason.
This was not giving me any issues until I was configuring "Weblogic Cluster" value(instead of "Weblogic Host") in the OHS layer pointing to the Webcenter managed servers.Once I did so,the Webcenter Portal page would not load and instead would give me a flickering page with consistently changing values of adf_ctrl.state and the page would not load up.
This issue was resolved once I added WLCookieName <cookieName> under the context root tag for the Webcenter Portal app in mod_wl_ohs.conf

This post is also relevant in this regard.