HTTP session data replication

Single admin server and two managed servers in a cluster. Using NES plugin API from three web servers to the cluster. EJB is deployed with PersistenceStore=Memory.
Session data is not replicating. Cluster is configured for Round-robin. One jsp hits server (A) the next hits server (B). Well,
server (B) requires the session data from the first jsp.
Anyone have any idea where I should look next to troubleshoot this.
TIA

Hi.
You need to make sure you have PersistentStoreType set in your weblogic.xml as follows in order to replicate http session data:
<session-descriptor>
<session-param>
<param-name> PersistentStoreType </param-name>
<param-value> replicated </param-value>
</session-param>
</session-descriptor>
HTH,
Michael
Tim Perkins wrote:
Single admin server and two managed servers in a cluster. Using NES plugin API from three web servers to the cluster. EJB is deployed with PersistenceStore=Memory.
Session data is not replicating. Cluster is configured for Round-robin. One jsp hits server (A) the next hits server (B). Well,
server (B) requires the session data from the first jsp.
Anyone have any idea where I should look next to troubleshoot this.
TIA--
Michael Young
Developer Relations Engineer
BEA Support

Similar Messages

First Hit Session Data Replication

We are using WLS 5.1 with sp3 in a cluster of three
          servers using in-memory-rep, JSP, and Apache as our proxy.
          Session data replication between a primary and secondary server
          seems to work fine except in the following case:
          1) Make first hit to the cluster. During the JSP processing of
          that hit set some HTTP session data via setAttribute().
          2) Kill-off the primary server (the one that handled the first hit).
          3)Make a second hit to the cluster, it is handled by another
          server (the secondary), the session is recognized as an ongoing
          session however the session data that was set during the first hit is not
          present in the second hit.
          If we make two hits to the first server and set data, then kill-off
          the primary server, the secondary has the data at the third hit. The
          only issue seems to be when the primary is killed after the first hit.
          Anyone have any ideas?
          Thanks,
          -darren


You can configure ClusterServlet in your web server farm (WLAS as web
          servers) to proxy JSP and servlet requests to the WLAS farm (WLAS processing
          your JSP and servlet).
          Set up in-memory replication in your WLAS farm. Session in JSP will be
          replicated.
          Cheers - Wei
          Yen Liu <[email protected]> wrote in message
          news:[email protected]...
          > Hello,
          >
          > I read breifly the section on BEA's online documentation talking about
          in-memory
          > replication and clustering.
          >
          > In it, it mentioned the ClusterServlet and configuring the
          weblogic.properties
          > file to assign servlets to the ClusterServlet so that sessions will be
          handled
          > correctly and all.
          >
          > My question is, "what about JSP" I am using a lot of JSP pages which sets
          > session parameters for the specific user into session objects.
          >
          > Any tips, recommendations will be most helpful.
          >
          > Thanks,
          >
          > Yen Liu
          > 510/870-1169
          >
          > Prasad Peddada wrote:
          >
          > > Darren,
          > >
          > > It shouldn't be the case. After your first hit, when you kill the
          primary
          > > server, when you make your next request you should find all the info in
          the
          > > session. I will post again, if we find the same problem on monday in our
          test
          > > environment.
          > >
          > > Thanks
          > >
          > > Prasad
          > >
          > > Darren Kessler wrote:
          > >
          > > > We are using WLS 5.1 with sp3 in a cluster of three
          > > > servers using in-memory-rep, JSP, and Apache as our proxy.
          > > > Session data replication between a primary and secondary server
          > > > seems to work fine except in the following case:
          > > >
          > > > 1) Make first hit to the cluster. During the JSP processing of
          > > > that hit set some HTTP session data via setAttribute().
          > > > 2) Kill-off the primary server (the one that handled the first hit).
          > > > 3)Make a second hit to the cluster, it is handled by another
          > > > server (the secondary), the session is recognized as an ongoing
          > > > session however the session data that was set during the first hit is
          not
          > > > present in the second hit.
          > > >
          > > > If we make two hits to the first server and set data, then kill-off
          > > > the primary server, the secondary has the data at the third hit. The
          > > > only issue seems to be when the primary is killed after the first hit.
          > > >
          > > > Anyone have any ideas?
          > > >
          > > > Thanks,
          > > >
          > > > -darren
          >

HTTP Sessions tracking using in-memory session replication

          I am using wls5.1. I have a situation where the "Java Heap size
          used" exceeds 100%, then it drops down to maybe 20% (after garbage
          collection). What happens to the active Http sessions when using
          in-memory session replication with persistance set to false.
          Are the sessions written to disk? If so, where?
          Are the sessions, before the garbage collection, still active?


Also looks like either your session invalidation time is too high or your
          heap size is too small. Make sure you tune either of this paramater
          properly.
          Viresh Garg
          Principal Developer Relations Engineer
          BEA Systems
          Prasad Peddada wrote:
          > Replicated session data is never written to disk. I dont' understand
          > your second questions. If the session is active and if GC kicks in it
          > won't delete the object since the servlet engine has reference to that
          > session object.
          >
          > Make sure you never swap and your application has enough heap.
          >
          > -- Prasad
          >
          > chris mckinnon wrote:
          >
          > > I am using wls5.1. I have a situation where the "Java Heap size
          > > used" exceeds 100%, then it drops down to maybe 20% (after garbage
          > > collection). What happens to the active Http sessions when using
          > > in-memory session replication with persistance set to false.
          > > Are the sessions written to disk? If so, where?
          > > Are the sessions, before the garbage collection, still active?
          >
          > --
          > Cheers
          >
          > - Prasad

Http session replication fails in cluster

Hello everybody.
I have some problems with HTTP session replication in WebLlogic cluster environment. I have a cluster with 2 nodes and application deployed there. Application is configured with:
<session-param>
<param-name>PersistentStoreType</param-name>
<param-value>replicated</param-value>
</session-param>
in weblogic.xml
WebLogic plug-in for Apache webserver is configured properly as described in documentation.
But when I try to make experiment to enter the application, make some activities, look in console where I was redirected by apache proxy and manually shut down the node where request was sent, I loose my HTTP session with all data there (all the beans stored in session are Serializable). Replication doesn't work correctly. May be I've missed something in configuration? How can I configure my application to provide correctness session replication?
Thanks for advice.
Thanks

Thanks for response!
I'm using WebLogic 8.1 SP 4 and configured Apache proxy as described in documentation for load balancing. The only section I have in httpd.conf is next:
<Location /HTTPClnt>
     SetHandler weblogic-handler
</Location>
<IfModule mod_weblogic.c>
     WebLogicCluster serv1:7541,serv2:7541
     MatchExpression *.*
     Debug ON
     WLLogFile /www/tmp/global_proxy.log
     WLTempDir "/www/tmp"
     DebugConfigInfo On
     KeepAliveEnabled ON
     KeepAliveSecs 15
</IfModule>
<Location /myApp>
     SetHandler weblogic-handler
     WebLogicCluster serv1:7541,serv2:7541
</Location>and the string to include weblogic proxy module for apache:
LoadModule weblogic_module     modules/mod_wl_20.soI've configured CookiesEnabled=true in weblogic.xml, but it didn't help. About session specification in httpd.conf - where can I read about that? I've just configured apache according to manual from here:
[url http://e-docs.bea.com/wls/docs92/plugins/apache.html]http://e-docs.bea.com/wls/docs92/plugins/apache.html
Thanks

In-memory replication of http session is not working in BEA7 cluster

          Hi everyone,
          I have 3 managed servers in Bea7.0 SP4 in a cluster. The client requests are sent
          through apache web server. I have given cluster address as URL in httpd.conf of
          apache server which sends the client requests for dynamic pages such as JSPs and
          servlets to the weblogic cluster.
          Load balancing is working fine. I ensured this from the log files of all the 3
          servers. All the 3 servers are getting different client requests and thus load
          balancing is working.
          Now, I wanted to achieve Fail-over. I do not think that i should use proxy plug-in
          for this. I feel the cluster itself will handle fail-over provided i make the
          http session as memory replicated.
          I updated the weblogic.xml with the following entry :
          <session-descriptor>
          <param-name>PersistentStoreType</param-name>
          <param-value>replicated</param-value>
          </session-param>
          </session-descriptor>
          I guess this is sufficient to make the http session as cluster aware.
          But when I shutdown server1, the user connected to server1 will be kicked out
          of the session and come to login page through server2 or server3 which are running
          fine.
          Could anyone help me to achieve http session as cluster aware. Does it indicate
          that I have to go for WLS proxy – HttpClusterServlet to achieve fail over for
          http session ?
          BTW, for your info, i am using setAttribute() and getAttribute() while manipulating
          the session.
          thanks in advance.


          Hi Ryan,
          Thanks for ur valuable input.
          I can see failover working.
          But, I can not continue with the same session in my application.
          I printed session Ids before and after failover, I found both are different.
          I guess session replication is a responsibility of weblogic/apache plugin.
          If not please let me know which all settings I should do to make failover working?
          Thanks again.
          Plad
          "ryan upton" <ryanjupton at learningvoyage dot com> wrote:
          >Plad,
          >
          >Are you trying to gracefully shut down the server? If you are then the
          >problem that you say you can't identify is simply the server's default
          >behavior which is to wait for all non-replicated sessions to be dropped
          >or
          >timed out before killing the process. Try forcing the shutdown: kill
          >-9 the
          >PID or CTRL-C if you started the server from the command line. You can
          >also
          >check the ``Ignore Sessions During Shutdown" checkbox under the server's
          >control tab in the admin console, this should allow you to shut down
          >gracefully without waiting for session timeout. BTW your sequence is
          >off
          >in #5 below, the replication doesn't occur upon failure, the replication
          >has
          >already happened once you created the session object on the first server,
          >I
          >think maybe you're confusing replication with failover.
          >
          >~RU
          >
          >"Plad" <[email protected]> wrote in message
          >news:[email protected]...
          >>
          >> Hi,
          >> I have 2 managed servers in a cluster.
          >>
          >> 1. I have got a DNS name configured which maps to these 2 managed server's
          >IP
          >> addresses.
          >> 2. I can browse my site using this DNS name.
          >> In HTTPD.conf I have :
          >>
          >> ServerName dev.a.b.net
          >>
          >> <IfModule mod_weblogic.c>
          >> WebLogicCluster 10.1.38.232:7023,10.1.34.51:7023
          >> MatchExpression *.*
          >> </IfModule>
          >>
          >> LoadModule weblogic_module modules/mod_wl_20.so
          >>
          >> 3. I have adeded session descriptor in weblogic.xml , also enabled
          >proxy
          >plugin
          >> in weblogic console.
          >>
          >> 4. I tested accessing my application using DNS url after shutting down
          >alternatively
          >> each manaed server. I can access application.
          >>
          >> 5. Now, problem comes when I access a managed server1 , keeping server2
          >down.
          >> I am able to access my application.
          >> Now, I start the server2.
          >> (Here I am supposing that replication should occur)
          >> Then I am shutting down server1.
          >> But, this time the server log shows me following:
          >>
          >>
          >> 9:58:51 AM GMT+05:30 NOTICE Web application(s) chlist still have
          >non-replicated
          >> sessions after 2 minutes of initiating SUSPEND. Waiting for non-replicated
          >sessions
          >> to finish.
          >> 10:00:51 AM GMT+05:30 NOTICE Web application(s) chlist still have
          >non-replicated
          >> sessions after 4 minutes of initiating SUSPEND. Waiting for non-replicated
          >sessions
          >> to finish.
          >>
          >> I am unable to make out where the problem is?
          >> Can it be a problem of Liecense? Is there any specialcluster liecense
          >for
          >weblogic8?
          >>
          >> Hoping to get replies.
          >> Thanx.
          >> Plad
          >>
          >> "ryan upton" <ryanjupton at learningvoyage dot com> wrote:
          >> >See my reply to your first post, but I've also added a few comments
          >here.
          >> >
          >> >"jyothi" <[email protected]> wrote in message
          >> >news:[email protected]...
          >> >>
          >> >> I guess someone from bea support team only can answer both your
          >question
          >> >and mine.
          >> >> As per my knowledge, we do not need to do any setup at Apache
          >side
          >> >regarding
          >> >> cluster other than mentioning cluster address as URL while
          >contacting
          >> >WLS
          >> >> from apache.
          >> >>
          >> >> I hope someone from Bea, will help us. I do not think that we
          >> >go for
          >> >WLS
          >> >> proxy plug-in using HttpClusterServlet for making session replication.
          >> > I
          >> >strongly
          >> >> feel that the cluster itself be able to manage the fail-over of
          >> >http
          >> >sessions
          >> >> provided we put the entry "PersistentStoreType" in weblogic.xml
          >> >regarding
          >> >> the session replication.
          >> >>
          >> >
          >> >The cluster does handle the management of Sessions. The clustered
          >> >applications still create the Session objects and the cluster manages
          >> >them
          >> >as per your deployment descriptor settings (replicated, JDBC, File)
          >however
          >> >the proxy has to be aware of which server the client has an affinity
          >> >for
          >> >(only with replicated sessions) and it does that by reading a cookie
          >> >passed
          >> >back from the server that handled the initial request and created
          >the
          >> >primary session object. The proxy has a list of both the primary
          >and
          >> >secondary server locations from this cookie that it can use to failover
          >> >the
          >> >request if the primary server fails. Clusters _DO NOT_ failover nor
          >> >do they
          >> >load balance, that's the job of your proxy, whether you're using the
          >> >HTTPClusterServlet, WLS Plug-in or a more sophisticated hardware load
          >> >balancer like Big IPs F5
          >> >
          >> >> jyothi
          >> >>
          >> >
          >> >~RU
          >> >
          >> >
          >>
          >
          >

What are the steps to setup an HTTP Session replication clustering in oc4j9

what are the steps to setup an HTTP Session replication clustering in oc4j9.0.5

Are you sure you have the correct version number for OC4J? Is this a standalone OC4J instance, if it then the steps involved are different from the full stack. Please check the Higher Availibility guide in the documentation on OTN.
Deepak

HTTP Session Replication

Hi!
I'm trying to setup a cluster between two managed servers located on the same server. The following configuration is about my cluster. I just removed the secutiry element:
*<?xml version='1.0' encoding='UTF-8'?>*
*<domain xmlns="http://xmlns.oracle.com/weblogic/domain" xmlns:sec="http://xmlns.oracle.com/weblogic/security" xmlns:wls="http://xmlns.oracle.com/weblogic/security/wls" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.oracle.com/weblogic/security/xacml http://xmlns.oracle.com/weblogic/security/xacml/1.0/xacml.xsd http://xmlns.oracle.com/weblogic/security/providers/passwordvalidator http://xmlns.oracle.com/weblogic/security/providers/passwordvalidator/1.0/passwordvalidator.xsd http://xmlns.oracle.com/weblogic/domain http://xmlns.oracle.com/weblogic/1.0/domain.xsd http://xmlns.oracle.com/weblogic/security http://xmlns.oracle.com/weblogic/1.0/security.xsd http://xmlns.oracle.com/weblogic/security/wls http://xmlns.oracle.com/weblogic/security/wls/1.0/wls.xsd">*
*<name>caim</name>*
*<domain-version>10.3.2.0</domain-version>*
*<server>*
*<name>AdminServer</name>*
*<machine></machine>*
*<listen-address></listen-address>*
*</server>*
*<server>*
*<name>ManagedServer_1</name>*
*<machine></machine>*
*<listen-port>7003</listen-port>*
*<cluster>Cluster_1</cluster>*
*<listen-address></listen-address>*
*<server-start>*
*<arguments>-Djava.endorsed.dirs=C:\endorsed</arguments>*
*<password-encrypted>{AES}7iyQ50j7+efCMMUTHrSPcELzY9wjcge0W0Gp/HH3j9E=</password-encrypted>*
*</server-start>*
*<jta-migratable-target>*
*<name>ManagedServer_1</name>*
*<user-preferred-server>ManagedServer_1</user-preferred-server>*
*<cluster>Cluster_1</cluster>*
*</jta-migratable-target>*
*</server>*
*<server>*
*<name>ManagedServer_2</name>*
*<machine></machine>*
*<listen-port>7004</listen-port>*
*<cluster>Cluster_1</cluster>*
*<listen-address></listen-address>*
*<server-start>*
*<arguments>-Djava.endorsed.dirs=C:\endorsed</arguments>*
*<password-encrypted>{AES}PC7yN6hCVA3N6lMn2AyZgJu0pGcv4K5XUDUMmWMNE5Q=</password-encrypted>*
*</server-start>*
*<jta-migratable-target>*
*<name>ManagedServer_2</name>*
*<user-preferred-server>ManagedServer_2</user-preferred-server>*
*<cluster>Cluster_1</cluster>*
*</jta-migratable-target>*
*</server>*
*<cluster>*
*<name>Cluster_1</name>*
*<cluster-messaging-mode>unicast</cluster-messaging-mode>*
*</cluster>*
*<production-mode-enabled>true</production-mode-enabled>*
*<embedded-ldap>*
*<name>caim</name>*
*<credential-encrypted>{AES}BQResE+Zs6gOOTGLqF3T70xcLs3AVw2F7+7sNKLdb2T+QE3cx+zHFlO0RQyBAZy1</credential-encrypted>*
*</embedded-ldap>*
*<configuration-version>10.3.2.0</configuration-version>*
*<app-deployment>*
*<name>app</name>*
*<target>ManagedServer_1</target>*
*<module-type>war</module-type>*
*<source-path>C:\WebLogic\app</source-path>*
*<deployment-order>100</deployment-order>*
*<security-dd-model>DDOnly</security-dd-model>*
*</app-deployment>*
*<app-deployment>*
*<name>app2</name>*
*<target>ManagedServer_2</target>*
*<module-type>war</module-type>*
*<source-path>C:\WebLogic\app2</source-path>*
*<security-dd-model>DDOnly</security-dd-model>*
*</app-deployment>*
*<machine>*
*<name></name>*
*<node-manager>*
*<name></name>*
*<listen-address></listen-address>*
*</node-manager>*
*</machine>*
*<migratable-target>*
*<name>ManagedServer_1 (migratable)</name>*
*<notes>This is a system generated default migratable target for a server. Do not delete manually.</notes>*
*<user-preferred-server>ManagedServer_1</user-preferred-server>*
*<cluster>Cluster_1</cluster>*
*</migratable-target>*
*<migratable-target>*
*<name>ManagedServer_2 (migratable)</name>*
*<notes>This is a system generated default migratable target for a server. Do not delete manually.</notes>*
*<user-preferred-server>ManagedServer_2</user-preferred-server>*
*<cluster>Cluster_1</cluster>*
*</migratable-target>*
*<admin-server-name>AdminServer</admin-server-name>*
*</domain>*
I do not see any log about http session replication and when I stop the managed server that is handling the requests, the application is redirected to the login page, i.e., there's no session replication.
Need I to do something more than create the cluster and add the managed servers to the cluster?
Is it possible to enable the logging to the session replication?
Best Regards,
A.

Please refer to : http://jaysensharma.wordpress.com/2009/12/08/session-replication-issues/
To identify Session Replication requirements ...and Causes...
Like *"weblogic.xml"* should contain:
<persistance-type> Tag... Like following:
<font color=maroon>
<session-descriptor>
<persistent-store-type>replicated</persistent-store-type>
</session-descriptor>
</font>
Can you please enable SessionReplication related Debug Flags from AdminConsole....?
Are you using any kind of Proxy/LoadBalancer in front of your Cluster?
Have you ever tried changing default HttpSession Cookie Name from "*JSESSIONID"* to something else?
Thanks
Jay SenSharma

HTTP Session replication problem

Hi all,
After 3 days trying to make the http session replication work in my cluster is time to ask some help.
I´m trying to make a simple application (only a servlet) simulate a http session replication.
I´ve investigated all the possible problems that i encountered in google :
Here is my multicast tests :
SERVER 1
D:\>java -cp d:\bea\weblogic92\server\lib\weblogic.jar utils.MulticastTest -N SE
RVER1 -A 237.0.0.1 -p 12809
***** WARNING ***** WARNING ***** WARNING *****
Do NOT use the same multicast address as a running WLS cluster.
Starting test. Hit any key to abort
Using multicast address 237.0.0.1:12809
Will send messages under the name SERVER1 every 2 seconds
Will print warning every 600 seconds if no messages are received
I (SERVER1) sent message num 1
I (SERVER1) sent message num 2
Received message 2 from SERVER1
I (SERVER1) sent message num 3
Received message 3 from SERVER1
I (SERVER1) sent message num 4
Received message 4 from SERVER1
I (SERVER1) sent message num 5
Received message 5 from SERVER1
I (SERVER1) sent message num 6
Received message 6 from SERVER1
I (SERVER1) sent message num 7
Received message 7 from SERVER1
I (SERVER1) sent message num 8
Received message 8 from SERVER1
I (SERVER1) sent message num 9
Received message 9 from SERVER1
I (SERVER1) sent message num 10
Received message 10 from SERVER1
Received message 11 from SERVER1
I (SERVER1) sent message num 11
I (SERVER1) sent message num 12
Received message 12 from SERVER1
I (SERVER1) sent message num 13
Received message 13 from SERVER1
Received message 14 from SERVER1
I (SERVER1) sent message num 14
I (SERVER1) sent message num 15
Received message 15 from SERVER1
I (SERVER1) sent message num 16
Received message 16 from SERVER1
SERVER 2
D:\>java -cp d:\bea\weblogic92\server\lib\weblogic.jar utils.MulticastTest -N SE
RVER2 -A 237.0.0.1 -p 12809
***** WARNING ***** WARNING ***** WARNING *****
Do NOT use the same multicast address as a running WLS cluster.
Starting test. Hit any key to abort
Using multicast address 237.0.0.1:12809
Will send messages under the name SERVER2 every 2 seconds
Will print warning every 600 seconds if no messages are received
I (SERVER2) sent message num 1
I (SERVER2) sent message num 2
Received message 2 from SERVER2
I (SERVER2) sent message num 3
Received message 3 from SERVER2
I (SERVER2) sent message num 4
Received message 4 from SERVER2
I (SERVER2) sent message num 5
Received message 5 from SERVER2
I (SERVER2) sent message num 6
Received message 6 from SERVER2
I (SERVER2) sent message num 7
Received message 7 from SERVER2
I (SERVER2) sent message num 8
Received message 8 from SERVER2
I (SERVER2) sent message num 9
Received message 9 from SERVER2
I (SERVER2) sent message num 10
Received message 10 from SERVER2
I (SERVER2) sent message num 11
Received message 11 from SERVER2
I (SERVER2) sent message num 12
Received message 12 from SERVER2
Weblogic.XML descriptor
<session-descriptor>
          <session-param>
               <param-name>PersistentStoreType</param-name>
               <param-value>replicated</param-value>
          </session-param>
</session-descriptor>
CODE of the Servlet
HttpSession session = request.getSession();
          String sessionIdentif = (String)session.getAttribute("SESSIONIDENTIF");
          boolean boolNewSession = true;
          if(sessionIdentif == null) {
               session.setAttribute("SESSIONIDENTIF", "1234567890");
          } else
               boolNewSession = false;
As you can see the object that i put in session is a String, so Serializable....
All the requirements are validated (i think...) but it still not working ... i get the SESSION ID : WvHQMKzBh9T35BPhGJxyhQtGks5Q3qJmxnJwGn8mn7V24FM92cnh!949557342! NONE !1284141857480
And the NONE said that the session isn´t replicated.
Any idea what´s wrong with my try of getting http session replication working??
cheers,

Hi,
Thanks for your help.
I´ve tried your application with your proxy application but still no work...
I´m getting :
####<13/Set/2010 15H59m BST> <Debug> <Replication> <DST01VS51> <VIACTT2> <[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <> <> <1284389948055> <000000> <Creating primary 1678977133045201960>
####<13/Set/2010 15H59m BST> <Debug> <ReplicationDetails> <DST01VS51> <VIACTT2> <[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <> <> <1284389948055> <000000> <Unable to create secondary for 1678977133045201960 on null>
####<13/Set/2010 15H59m BST> <Debug> <ReplicationDetails> <DST01VS51> <VIACTT2> <[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <> <> <1284389948181> <000000> <Unable to create secondary for 1678977133045201960 on null>
In my early post i forgot to mention that i´m using an Apache 2.2 in the front-end with Weblogic 9.2 (cluster).
What is happening in this weblogic configuration so that this session replication don´t work.
cheers,

Session State Replication of Referenced Objects

Here is question on Clustering and Session state replication:
          Scenario:
          Consider two Session Objects A and B.
          Object A has-a reference to object B.
          So whatever changes done to Object B is reflected in Object A.
          In-memory Session replication happens on every HttpSession.setAttribute() call.
          The question is will the two session objects(A and B) be replicated to the other cluster and will still maintain the reference relationship or will they be two separate objects with same data (in different memory locations).
          regards,
          Jaiganesh

Ok, I have been meaning to dig into session replication in a bit more detail and your question is a good excuse to do it!
          First stop the docs:
          Bea Docs
          The bits that jump out are under:
          Programming Considerations for Clustered Servlets and JSPs
          1) Session Data Must Be Serializable, so both your objects are serializable.
          2) Use setAttribute to Change Session State In an HTTP servlet that implements javax.servlet.http.HttpSession, use HttpSession.setAttribute (which replaces the deprecated putValue) to change attributes in a session object. If you set attributes in a session object with setAttribute, the object and its attributes are replicated in a cluster using in-memory replication. If you use other set methods to change objects within a session, WebLogic Server does not replicate those changes. Every time a change is made to an object that is in the session, setAttribute() should be called to update that object across the cluster.
          Likewise, use removeAttribute (which, in turn, replaces the deprecated removeValue) to remove an attribute from a session object.
          >Will the reference as shown in the step 3 will be >maintained after replication on the other cluster ?? I >guess not!!
          I don't understand "on the other cluster" There is normally one cluster made up of a few servers. The session state is maintained on one primary server and a secondary server. So you have aObj.a2 = bObj, from the docs I would understand that at the momment you called session.setAttribute the aObj and all its fields provided they are seriliazable will be replicated in Mememory.
          >There the aObj and bObj stored in the two different >session objects will not have a reference relationship >in other words if i change bObj on the other cluster >will the reference a2 of aObj be able see it ??
          This is testing the limits of my understanding, but would have thought if the objects are in different sessions they should not be able to reference each other in the manner I think you are suggesting, so if I access aObj.a2 (an instance of bObj) and changed it in one session it should not affet any other bObj unless bObj is a singleton....I think!
          What say you?

How can I flag HTTP session attributes to not be replicated ?

          WLS 5.1 SP8 - In memory replication of a stateful servlet. Is
          there any way to flag data that has been, or is being, loaded into
          a HTTP session so as to not be replicated ? It's a long story,
          but we have some data loaded into a hashtable, more specifically
          a Properties object, stored in our session. With the hastable
          already loaded into the HTTP session, weblogic does not detect
          when we add values to the table, and therefore does not replicate
          the changes. Which is ok since WLS is working as designed. To
          get around this we load the hashtable back into the session everytime
          we add a value to the hashtable. Yup, I know that's ugly. Anyway,
          what I'm trying to find out if is there is an attribute that we
          can set to indicate, to not replicate this data or that data.
          Something along the lines of a attribute on a per hastable value
          basis. For example, I load value A into my hashtable, then I
          need to put my hashtable into the session to get it replicated.
          Next I load value B into the hastable, and again to get it replicated
          I have to load the entire hashtable back into the session. The
          problem here is that the entire table gets replciated. Does anyone
          know if I can set an attribute on value A, when I'm adding value
          B, so as to not replicate value A when I reload the table ? Of
          course all goal is to not store so much data in the session, but
          I'm trying to find a work around until that is completed.
          Thanks,
          David


          Where can I find documentation on the details of how Weblogic decides what will
          be replicated in the HTTPSession object (for example, it only replicates attributes
          which are set or updated using "setAttribute()"?
          Prasad Peddada <[email protected]> wrote:
          >Robert,
          >
          > It is true that we replicate only when you call setAttribute in case
          >of servlets.
          >
          >In case of EJB it is slightly different. EJB sends diff's across the
          >wire. It doesn't
          >replicate the entire state with every request.
          >
          >-- Prasad
          >
          >Chris Palmer wrote:
          >
          >> I think Viresh was referring to modifying part of one attribute causing
          >the whole
          >> of that attribute (i.e. the hashtable) to be replicated.
          >>
          >> Is it actually true though that the behaviour would be different in
          >a stateful
          >> session EJB? I had assumed that the WHOLE ejb state would be replicated
          >each time
          >> (i.e. after each invocation), without even the benefit of having a
          >mechanism such
          >> as setAttribute() to flag the attributes that had changed...
          >>
          >> Chris
          >>
          >> Robert Patrick wrote:
          >>
          >> ? Huh? Since when does it always replicate the entire HttpSession?
          > We were
          >> ? told that it uses a hook in the setAttribute() call to determine
          >which
          >> ? attributes have changed and only replicates those attributes. I
          >know this to
          >> ? be the case because if I retrieve a previously stored attribute from
          >the
          >> ? HttpSession and modify it, my changes do not get replicated unless
          >I call
          >> ? setAttribute again...
          >> ?
          >> ? Robert
          >> ?
          >> ? Viresh Garg wrote:
          >> ?
          >> ? ? Servlet sessions don't work on diffs, so no matter what you do,
          >entire
          >> ? ? Hashtable will be replicated. If you want the optimization for
          >only
          >> ? ? replicating the diff ( the stuff that has changed between 2 updates)
          >,
          >> ? ? consider using stateful session bean and having hashtable part
          >of
          >> ? ? conversational state of stateful session bean.
          >> ? ?
          >> ? ? The solution that you suggested on your own for your problem is
          >not ugly
          >> ? ? as the same solution is used by many customers that I know of.
          >This is
          >> ? ? particularly a problem for people that use Java Beans and use the
          >set
          >> ? ? Property directive of Java Bean in JSP. There also in our auto
          >generated
          >> ? ? code, we put the JavaBean back in HTTP Session, when a setter is
          >called to
          >> ? ? enforce replication.
          >> ? ?
          >> ? ? Keep in mind that whatever we do for replication, we want to support
          >it
          >> ? ? using ONLY standard servlet API and we don't want to introduce
          >any WLS
          >> ? ? specific API to achieve this, and so putting value back in session
          >is the
          >> ? ? only way.
          >> ? ?
          >> ? ? Viresh Garg
          >> ? ? Principal Developer Relations Engineer
          >> ? ? BEA Systems
          >> ? ?
          >> ? ? Dave Javu wrote:
          >> ? ?
          >> ? ? ? WLS 5.1 SP8 - In memory replication of a stateful servlet.
          >Is
          >> ? ? ? there any way to flag data that has been, or is being, loaded
          >into
          >> ? ? ? a HTTP session so as to not be replicated ? It's a long story,
          >> ? ? ? but we have some data loaded into a hashtable, more specifically
          >> ? ? ? a Properties object, stored in our session. With the hastable
          >> ? ? ? already loaded into the HTTP session, weblogic does not detect
          >> ? ? ? when we add values to the table, and therefore does not replicate
          >> ? ? ? the changes. Which is ok since WLS is working as designed.
          >To
          >> ? ? ? get around this we load the hashtable back into the session everytime
          >> ? ? ? we add a value to the hashtable. Yup, I know that's ugly.
          >Anyway,
          >> ? ? ? what I'm trying to find out if is there is an attribute that
          >we
          >> ? ? ? can set to indicate, to not replicate this data or that data.
          >> ? ? ? Something along the lines of a attribute on a per hastable value
          >> ? ? ? basis. For example, I load value A into my hashtable, then
          >I
          >> ? ? ? need to put my hashtable into the session to get it replicated.
          >> ? ? ? Next I load value B into the hastable, and again to get it replicated
          >> ? ? ? I have to load the entire hashtable back into the session. The
          >> ? ? ? problem here is that the entire table gets replciated. Does
          >anyone
          >> ? ? ? know if I can set an attribute on value A, when I'm adding value
          >> ? ? ? B, so as to not replicate value A when I reload the table ?
          >Of
          >> ? ? ? course all goal is to not store so much data in the session,
          >but
          >> ? ? ? I'm trying to find a work around until that is completed.
          >> ? ? ? Thanks,
          >> ? ? ? David
          >

NullPointerException: Could not deserialize session data

Hi all,
I am getting this exception on the portal application again and again. Can somebody help me out with this?
####Sept 29, 2007 2:34:23 PM EST> <Error> <HTTP Session> <beapweb1> <HUSLM01> <ExecuteThread: '3' for queue: 'weblogic.kernel.System'> <<anonymous>> <> <BEA-100028> <Could not deserialize session data.
java.lang.NullPointerException
     at com.bea.wlw.netui.pageflow.FlowController.valueUnbound(FlowController.java:1968)
     at com.bea.wlw.netui.pageflow.PageFlowController.valueUnbound(PageFlowController.java:643)
     at weblogic.servlet.internal.session.SessionData.removeAttribute(SessionData.java:543)
     at weblogic.servlet.internal.session.SessionData.removeAttribute(SessionData.java:345)
     at weblogic.servlet.internal.session.ReplicatedSessionData.removeAttribute(ReplicatedSessionData.java:597)
     at weblogic.servlet.internal.session.SessionData.remove(SessionData.java:854)
     at weblogic.servlet.internal.session.ReplicatedSessionData.remove(ReplicatedSessionData.java:312)
     at weblogic.servlet.internal.session.ReplicatedSessionContext.invalidateSession(ReplicatedSessionContext.java:567)
     at weblogic.servlet.internal.session.SessionContext$InvalidationAction.run(SessionContext.java:612)
     at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:323)
     at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:101)
     at weblogic.servlet.internal.session.SessionContext$SessionInvalidator.cleanupExpiredSessions(SessionContext.java:560)
     at weblogic.servlet.internal.session.SessionContext$SessionInvalidator.trigger(SessionContext.java:467)
     at weblogic.time.common.internal.ScheduledTrigger.run(ScheduledTrigger.java:293)
     at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:323)
     at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:101)
     at weblogic.time.common.internal.ScheduledTrigger.executeLocally(ScheduledTrigger.java:229)
     at weblogic.time.common.internal.ScheduledTrigger.execute(ScheduledTrigger.java:213)
     at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:214)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:179)
The application is on WebLogic Portal 8.1 SP5 and it's on a cluster.
Any help would be greatly appreciated.
Thanks
Sam

Hi
you seem to have session replication turned on in your cluster .
In which case any private member variable in any pageflow must be serializable for the session replication to work.(or marked as transient etc.)
regards
deepak

"Could not deserialize session data" error during sign out

Hello,
I have an application deployed on WLS 8.1, one instance, no clustering. The application EAR contains 1 web module and 2 ejb modules. When I try to sign out(I use Single Sign-On for Multiple Applications - a sign out application deployed separately) I receive the attached error.
Notes: my session is serializable - I did a test that serialize and deserialize the session and I have no errors.
Q: Why does WLS try to deserialize the session data during sign out? I don't use any session persistance/replication.
The error ClassNotFoundException from my point of view is normal: UsersTableModel(from web modile) is not visible from the Application Classloader.
Here is the error:
<> <BEA-100028> <Could not deserialize session data.
java.lang.ClassNotFoundException: xxx.controller.actions.UsersTableModel: This error could indicate that a component was deployed on a cluster member but not other members of that cluster. Make sure that any component deployed on a server that is part of a cluster is also deployed on all other members of that cluster
     at weblogic.j2ee.ApplicationManager.loadClass(Ljava.lang.String;Ljava.lang.String;Ljava.lang.String;Ljava.lang.ClassLoader;Z)Ljava.lang.Class;(ApplicationManager.java:344)
     at weblogic.j2ee.ApplicationManager.loadClass(Ljava.lang.String;Ljava.lang.String;Ljava.lang.String;Ljava.lang.ClassLoader;)Ljava.lang.Class;(ApplicationManager.java:258)
     at weblogic.j2ee.ApplicationManager.loadClass(Ljava.lang.String;Ljava.lang.String;Ljava.lang.String;)Ljava.lang.Class;(ApplicationManager.java:253)
     at weblogic.j2ee.ApplicationManager.loadClass(Ljava.lang.String;Ljava.lang.String;)Ljava.lang.Class;(ApplicationManager.java:216)
     at weblogic.common.internal.WLObjectInputStream.resolveClass(Ljava.io.ObjectStreamClass;)Ljava.lang.Class;(WLObjectInputStream.java:48)
     at java.io.ObjectInputStream.readNonProxyDesc(Z)Ljava.io.ObjectStreamClass;(Unknown Source)
     at java.io.ObjectInputStream.readClassDesc(Z)Ljava.io.ObjectStreamClass;(Unknown Source)
     at java.io.ObjectInputStream.readOrdinaryObject(Z)Ljava.lang.Object;(Unknown Source)
     at java.io.ObjectInputStream.readObject0(Z)Ljava.lang.Object;(Unknown Source)
     at java.io.ObjectInputStream.readObject()Ljava.lang.Object;(Unknown Source)
     at weblogic.servlet.internal.AttributeWrapper.convertBytesToObject([B)Ljava.lang.Object;(AttributeWrapper.java:173)
     at weblogic.servlet.internal.AttributeWrapper.getObject(Z)Ljava.lang.Object;(AttributeWrapper.java:114)
     at weblogic.servlet.internal.AttributeWrapper.getObject()Ljava.lang.Object;(AttributeWrapper.java:69)
     at weblogic.servlet.internal.session.SessionData.removeAttribute(Ljava.lang.String;Z)Ljava.lang.Object;(SessionData.java:614)
     at weblogic.servlet.internal.session.SessionData.removeAttribute(Ljava.lang.String;)V(SessionData.java:596)
     at weblogic.servlet.internal.session.SessionData.remove()V(SessionData.java:808)
     at weblogic.servlet.internal.session.MemorySessionContext.invalidateSession(Lweblogic.servlet.internal.session.SessionData;)Z(MemorySessionContext.java:69)
     at weblogic.servlet.internal.session.SessionData.invalidate()V(SessionData.java:750)
     at weblogic.servlet.security.ServletAuthentication.invalidateAll(Ljavax.servlet.http.HttpServletRequest;)Z(ServletAuthentication.java:184)
     at xxx.framework.authentication.WebAuthenticationHelper.invalidateSessions(Ljavax.servlet.http.HttpServletRequest;)V(WebAuthenticationHelper.java:574)
     at xxx.framework.authentication.WebAuthenticationHelper.closeSession(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(WebAuthenticationHelper.java:523)
     at xxx.framework.authentication.WebAuthenticationHelper.logout(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(WebAuthenticationHelper.java:250)
     at xxx.yyy.ViewDispatcher.process(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(ViewDispatcher.java:75)
     at xxx.yyy.ViewDispatcher.doGet(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(ViewDispatcher.java:42)
     at javax.servlet.http.HttpServlet.service(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(HttpServlet.java:740)
     at javax.servlet.http.HttpServlet.service(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;)V(HttpServlet.java:853)
     at weblogic.servlet.internal.ServletStubImpl$ServletInvocationAction.run()Ljava.lang.Object;(ServletStubImpl.java:996)
     at weblogic.servlet.internal.ServletStubImpl.invokeServlet(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;Lweblogic.servlet.internal.FilterChainImpl;)V(ServletStubImpl.java:419)
     at weblogic.servlet.internal.ServletStubImpl.invokeServlet(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;)V(ServletStubImpl.java:315)
     at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run()Ljava.lang.Object;(WebAppServletContext.java:6452)
     at weblogic.security.acl.internal.AuthenticatedSubject.doAs(Lweblogic.security.subject.AbstractSubject;Ljava.security.PrivilegedAction;)Ljava.lang.Object;(AuthenticatedSubject.java:321)
     at weblogic.security.service.SecurityManager.runAs(Lweblogic.security.acl.internal.AuthenticatedSubject;Lweblogic.security.acl.internal.AuthenticatedSubject;Ljava.security.PrivilegedAction;)Ljava.lang.Object;(SecurityManager.java:118)
Edited by: user11291053 on 22-Jun-2009 02:52
Edited by: user11291053 on 22-Jun-2009 03:01
Edited by: user11291053 on 23-Jun-2009 01:42

When OptimisticSerialization is turned on, WebLogic server does not serialize-deserialize context and request attributes upon getAttribute(name) when a request gets dispatched across servlet contexts. This means you will need to make sure that the attributes common to Web applications are scoped to a common parent classloader (they are application-scoped) or placed in the system classpath if the two Web applications do not belong to the same application.
When OptimisticSerialization is turned off (which is the default) WebLogic Server does serialize-deserialize context and request attributes upon getAttribute(name) to avoid the possibility of ClassCastExceptions. The value of OptimisticSerialization can also be overridden for specific Web applications by setting the optimistic-serialization value in weblogic.xml.
[http://edocs.bea.com/wls/docs100/ConsoleHelp/pagehelp/Corecoredomaindomainconfigwebapptitle.html]
[http://e-docs.bea.com/wls/docs90/webapp/weblogic_xml.html#1067857]
I hope this helps :)

How to replicate session data at the user level?

Hi all,
my client has users who use laptop/tablet computers in the field with wireless connections. The application requires the users to complete long multi-page forms where the data is only submitted to the EIS layer at the end of the process. The connections regularly drop out which understandably is a cause of some grief. In addition, the users want to be able to switch to another machine in order to complete their session.
The 'switching machine' requirement kills the idea of using persistent cookies and session replication unfortunately. So I am faced with the idea of storing the session data (keyed by user id), in serialized form, either on a stand-alone disk which is accessible by each webserver in the cluster or is the database. The problem with the database idea is the performance hit of traversing the EJB and JDBC layers.
Can anyone suggest the best practice in this case? Or point to an article or tool that covers the problem?
BTW, the app serves a small (<50) and stable base of authenticated users so scalability is not really an issue whereas failover is.
Regards,
Dave.

> Is it possible to close a PO at the header level
Po can be closed at Item level and not Header level. You can set Deletion Indicator and further can be archived thru SARA MM_EKKO
or a way to deactivate the PO so that no new items can be added?
You can activate Release strategy and Choose a Proper Release indicatory so that no new changes to be carried out.
Else go for User Exits

Why I get "Error in getting session data" error when running report?

Hello,
I have reporting services on one server, and SharePoint 2010 on other server. When I view report from browser, I got blank page. From Report Server Log file, I got below error:
v VERBOSE: writting session cookie: ekkrjbubp00t5wzc3rzspvzb
v VERBOSE: Saved report snapshot to session in a background thread <for same session id>
e ERROR: Throwing Microsoft.ReportingServices.Diagnostics.Utilities.ReportServerStorageException: , An error occurred within the report server database. This may be due to a connection failure, timeout or low disk condition within the database.;
e ERROR: Error in getting session data: Expired Session: ekkrjbubp00t5wzc3rzspvzb
e ERROR: Throwing Microsoft.ReportingServices.Diagnostics.Utilities.ExecutionNotFoundException: , Microsoft.ReportingServices.Diagnostics.Utilities.ExecutionNotFoundException: The report execution ekkrjbubp00t5wzc3rzspvzb has expired or cannot be found
Are there anyone getting the same issue as mine? I did not see any solutions for this issue when I searched.
Thanks,
Megan

There are a number of timeouts in SSRS; session timeout, report execution timeouts, http request timeouts. A session timeout in SSRS is not the same as a session timeout in ASP.NET. Below are some articles that can help you understand the timeouts
and hopefully lead you down the path of discovery.
This articles is a good article as it discusses the session timeout and the keep alive that is sent from the report viewer.
http://blogs.msdn.com/b/jgalla/archive/2006/10/11/session-timeout-during-execution.aspx
This article is good as well in describing some of the timeouts.
http://blogs.msdn.com/b/dynamicsaxbi/archive/2013/02/14/how-to-addressing-ssrs-session-timeouts.aspx

ERROR: Error in getting session data: Invalid or Expired Session

Hi,
We are using ssrs 2008 r2 and have a report which has links that allow the user to drill down.
When the link is clicked the same report is run but shows more detail. This works fine but we are now getting the error below for a user.
I have increased the time out for the report to 600 seconds.
Error in getting session data: Invalid or Expired Session: fnxgxhjuveugvd552qfyv3fw
session!ReportServer_0-6!4b0!03/18/2015-10:51:29:: i INFO: LoadSnapshot: Item with session: fnxgxhjuveugvd552qfyv3fw, reportPath: , userName: doman/user not found in the database
Any ideas how this can be resolved?

Hi Nasa1999,
Based on your error message, If the all the users will sometimes got the same issue, it can be caused by the timeout issue. It happens a lot when rendering big report, and it exceeds the default Session Timeout. You can execute script
to increase the Session Timeout time. Please refer to following blog:
Session Timeout during execution. Also increase the value of <Query Timeout> in rsreportserver.config file. This file locate at XX:\Program Files\Microsoft SQL Server\MSRS10.MSSQLSERVER\Reporting Services\ReportServer
Please also check to set the <legacyImpersonationPolicy> back to true(https://support.microsoft.com/en-us/kb/972328).
Locate the Aspnet.config file in the following folder:
%windir%\Microsoft.NET\Framework64\v2.0.50727
If Microsoft Visual Studio is installed on the computer that is running SQL Server 2005, double-click
Aspnet.config. If Visual Studio is not installed on the computer, follow these steps:
        a. Right-click Aspnet.config, point to
Open with, and then click Choose program.
        b. In the Programs list, click
Notepad, and then click OK.
Locate the following tag in the <runtime> section of the code.
        <legacyImpersonationPolicy enabled="false"/>
Change the tag to:
        <legacyImpersonationPolicy enabled="true"/>
Save the Aspnet.config file.
Reset IIS.
Try your report again.
Similar Thread for your reference:
Using SharePoint Report Viewer
Web Part: Error in getting session data: Invalid or Expired Session: xxxxxxxxxxx
If only the one user or several users will got the issue, the issue can be caused by the permission setting, please reference to below blog:
http://answers.flyppdevportal.com/categories/sqlserver/sqlreportingservices.aspx?ID=3506231b-9f4d-4f5a-884d-157137c56336
http://blog.goobol.com/the-permissions-granted-to-user-domainusername-are-insufficient-for-performing-this-operation/
If your problem still exists, please try to provide more details information as below:
Did you reporting service installed in native mode or sharepoint mode, If in native mode, please try to provide more error message from the log file:
C:\Program Files\Microsoft SQL Server\MSRS10_50.MSSQLSERVER\Reporting Services\LogFiles
If you still have any problem, please feel free to ask.
Regards,
Vicky Liu
Vicky Liu
TechNet Community Support

HTTP session data replication

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