PQ65772, 4.0.2,4.0.3: Application Server hang with
IIOP Tunneling Servlet
Downloadable files
Abstract
Using Internet Inter-ORB Protocol (IIOP) tunneling, a
second call will cause a hang.
Download Description
PQ65772 resolves the following problem:
USERS AFFECTED:
All WebSphere® Application Server users of the IIOP Tunneling feature.
PROBLEM DESCRIPTION:
Unable to start a second session of IIOPTunnelServlet and its associated
EJB™ until the first session is completed. IIOPTunnelServlet is a special
servlet developed by IBM WebSphere Java ORB team to allow HTTP client, for
example a Java client or HTTP browser, embedding with RMI-IIOP to
communicate with WebSphere Application Server as follows:
After the client is invoked, an HTTP request will be routed toward the
IIOPTunnelServlet.
IIOPTunnelServlet first intercepts the HTTP request from the client,
and then decodes and removes the RMI-IIOP out of the HTTP request.
It then creates and establishes an endpoint between itself and its
back-end EJB, and caches the endpoint as well.
At this moment, IIOPTunnelServlet switches to use RMI-IIOP instead of
HTTP for communicating with the EJB for service. When the EJB result is
returned, IIOPTunnelServlet encodes and seals the RMI-IIOP message within
the HTTP response and then dispatches this HTTP response back to the
client. The protocol being used between IIOPTunnelServlet and EJB is
RMI-IIOP. The protocol being used between the client, for example Java
client or browser, and IIOPTunnelServlet is HTTP.
Since the endpoint is cached in step 3, IIOPTunnelServlet does not always
create a new endpoint for every HTTP request. When a current session is in
the middle of the process, the IIOPTunnelServlet endpoint is used.
Therefore, the user is unable to start a second session of
IIOPTunnelServlet and its EJB until the current session completes because
the endpoint is in use at that moment.
PROBLEM CONCLUSION:
To resolve this problem, a new server-side ORB property is being
introduced to allow the servlet to be multi-threaded:
com.ibm.ws.orb.services.redirector.UseMultipleSockets
Prerequisites
None
Installation instructions
Please review the readme.txt for detailed installation
instructions.