Session lost problem in Weblogic cluster and Iplanet proxy

Question

          We have an environment like this
          Iplanet 4.1--> Two Weblogic servers.(WLS 6.1 sp1)
          The Weblogic servers are not really clusterd, but we are using the Weblogic Cluster
          attribute in the obj.conf to configure the proxy (The Weblogic servers are really
          independant servers with the same application deployed).
          This is working fine in our development environment. No problem with session and
          load balancing. Although this architecture is not documented in Weblogic docs,
          I have seen several references to this type of architecture in the web and it
          seems to be working.
          Now we are into our pre-production environment. The same archictecture exists.
          Only the following differences
          1. Both the weblogic servers run on multihomed machines. We have bound the Weblogic
          servers to specific IP addresses using the Listen address option.
          2. The same IP addresses are there in the proxy plug-in conf file.
          3. There is a firewall between the Iplanet and Weblogic.
          Now if only one weblogic is running, the application works fine. The moment we
          turn the other weblogic on, the application starts misbehaving. The session seems
          to get lost and proxy forwards requests randomly.
          What could be the reason?
          Regards
          Anup
          

Answer 1

          Hi
          The problem got solved. There was an older version of libproxy.so in the Iplanet
          proxy
          Regards
          Anup
          Yeshwant Kamat <[email protected]> wrote:
          >Anup,
          >
          >Is there a reason you are not clustering the WLS instances? Remove the
          >firewall in your
          >prod environment and see if that makes a difference.
          >
          >Anup wrote:
          >
          >> Hi Mike
          >> 1. As per the documentation WebLogic Server is set up to handle session
          >tracking
          >> by default. So we are not doing anything special. Since the application
          >works
          >> fine with one Weblogic and multiple clients connecting to it through
          >Iplanet ,
          >> I think there is no problem with Session tracking as such.
          >>
          >> 2.We are using the default cookie name for session (JSESSIONID). So
          >we haven't
          >> done anything extra in the proxy set up or weblogic.xml
          >>
          >> 3. I have watched the cookie that comes on the browser
          >> PAACk3iviDm4ZuMPIbB9TpTTw9slk40IEC02MKjpu14EZ9ayzqaP!-1196227542!gmbpds054!7015!7016.
          >>
          >> gmbpds054 is the DNS name of one of the weblogic servers. So that is
          >also fine.
          >>
          >> What else could be the problem.
          >> Regards
          >> Anup
          >>
          >> "Mike Reiche" <[email protected]> wrote:
          >> >
          >> >If you have session tracking turned on in weblogic, creating a session
          >> >will write
          >> >a cookie back to the browser. iPlanet does sticky load balancing
          >based
          >> >on the
          >> >IP address in this cookie. So -
          >> >
          >> >1) do you have session tracking turned on?
          >> >
          >> >2) is the cookie getting written to your browser?
          >> >
          >> >3) are iPlanet and WebLogic using the same cookie? (same name)
          >> >
          >> >Mike
          >> >
          >> >"Anup Maliyackel" <[email protected]> wrote:
          >> >>
          >> >>We have an environment like this
          >> >>
          >> >>Iplanet 4.1--> Two Weblogic servers.(WLS 6.1 sp1)
          >> >>
          >> >>The Weblogic servers are not really clusterd, but we are using the
          >Weblogic
          >> >>Cluster
          >> >>attribute in the obj.conf to configure the proxy (The Weblogic servers
          >> >>are really
          >> >>independant servers with the same application deployed).
          >> >>
          >> >>This is working fine in our development environment. No problem with
          >> >>session and
          >> >>load balancing. Although this architecture is not documented in Weblogic
          >> >>docs,
          >> >>I have seen several references to this type of architecture in the
          >web
          >> >>and it
          >> >>seems to be working.
          >> >>
          >> >>Now we are into our pre-production environment. The same archictecture
          >> >>exists.
          >> >>Only the following differences
          >> >>1. Both the weblogic servers run on multihomed machines. We have
          >bound
          >> >>the Weblogic
          >> >>servers to specific IP addresses using the Listen address option.
          >> >>
          >> >>2. The same IP addresses are there in the proxy plug-in conf file.
          >> >>
          >> >>3. There is a firewall between the Iplanet and Weblogic.
          >> >>
          >> >>Now if only one weblogic is running, the application works fine.
          >The
          >> >>moment we
          >> >>turn the other weblogic on, the application starts misbehaving. The
          >> >session
          >> >>seems
          >> >>to get lost and proxy forwards requests randomly.
          >> >>
          >> >>What could be the reason?
          >> >>
          >> >>Regards
          >> >>Anup
          >> >
          >