Replicated session state with WLS 5.1 sp 6 in cluster

Question

          Hello, i've seen in BEA documentation this:
          Applications Using Frames Must Coordinate Session Access
          If you are designing a web application that utilizes multiple frames, keep in mind
          that there is no synchronization of requests made by frames in a given frameset.
          For example, it is possible for multiple frames in a frameset to create multiple
          sessions on behalf of the client application, even though the client should logically
          create only a single session.
          In a clustered environment, poor coordination of frame requests can cause unexpected
          application behavior. For example, multiple frame requests can "reset" the application's
          association with a clustered instance, because the proxy plug-in treats each request
          independently. It is also possible for an application to corrupt session data by
          modifying the same session attribute via multiple frames in a frameset.
          To avoid unexpected application behavior, always use careful planning when accessing
          session data with frames. You can apply one of the following general rules to avoid
          common problems:
          ·     In a given frameset, ensure that only one frame creates and modifies session data.
          ·     Always create the session in a frame of the first frameset your application uses
          (for example, create the session in the first HTML page that is visited). After the
          session has been created, access the session data only in framesets other than the
          first frameset.
          My environment is clustered(multi-tier) and jsp and servlets use frameset, could
          you explane this?
          I don't understand very well
          Thanks and regards
          Fabio
          

Answer 1

          Thanks for you suggest!
          Fabio
          "Mike Reiche" <[email protected]> wrote:
          >
          >It means that all the jsps executed from the same browser use the same
          >httpsession
          >- so be aware of it.
          >
          >If the jsp in the first frame does ---
          >
          > httpSession.put("MYNAME", "GOODVALUE");
          >
          >and the jsp the second frame does ....
          >
          > httpSession.put("MYNAME", "BADVALUE");
          >
          >then the jsp in the first frame does ...
          >
          > value = httpSession.get("MYNAME");
          >
          >You might get "GOODVALUE" or you might get "BADVALUE" since both
          >JSPs execute concurrently without synchronization and they both store
          >something under
          >the same key in the same httpSession.
          >
          >Mike
          >
          >"Fabio Rossi" <[email protected]> wrote:
          >>
          >>Hello, i've seen in BEA documentation this:
          >>
          >>Applications Using Frames Must Coordinate Session Access
          >>
          >>If you are designing a web application that utilizes multiple frames,
          >keep
          >>in mind
          >>that there is no synchronization of requests made by frames in a given
          >frameset.
          >>For example, it is possible for multiple frames in a frameset to create
          >>multiple
          >>sessions on behalf of the client application, even though the client
          >should
          >>logically
          >>create only a single session.
          >>In a clustered environment, poor coordination of frame requests can
          >cause
          >>unexpected
          >>application behavior. For example, multiple frame requests can "reset"
          >the
          >>application's
          >>association with a clustered instance, because the proxy plug-in treats
          >>each request
          >>independently. It is also possible for an application to corrupt session
          >>data by
          >>modifying the same session attribute via multiple frames in a frameset.
          >>To avoid unexpected application behavior, always use careful planning
          >when
          >>accessing
          >>session data with frames. You can apply one of the following general
          >rules
          >>to avoid
          >>common problems:
          >>·     In a given frameset, ensure that only one frame creates and modifies
          >session
          >>data.
          >>
          >>·     Always create the session in a frame of the first frameset your application
          >>uses
          >>(for example, create the session in the first HTML page that is visited).
          >>After the
          >>session has been created, access the session data only in framesets
          >other
          >>than the
          >>first frameset.
          >>
          >>My environment is clustered(multi-tier) and jsp and servlets use frameset,
          >>could
          >>you explane this?
          >>I don't understand very well
          >>
          >>Thanks and regards
          >>Fabio
          >>
          >