Apache Sticky sessions

Question

I have configured a sticky session set up with a load balancer (Apache) and three app nodes running Jboss 4.2.2 . the load balancer uses mod_jk and settings as mentioned in the tutorial here.

http://community.jboss.org/wiki/UsingModjk12WithJBoss;jsessionid=1569CBFB7C3096C59C977CD3F7159A32

I have the jumRoute set as node1 ,node2 and node3 for the three nodes and my workerlist property for load balancer is set as node1,node2,node3

The tutorial has been followed till the last point but I did not configure the useJK parameters under.the value is still set to false. The sticky sessions are holding up but I seem to loose session and get this error in my mod_jk log file

[error] ajp_get_reply::jk_ajp_common.c (1926): (node1) Timeout with waiting reply from tomcat. Tomcat is down, stopped or network problems (errno=110)

I personally checked the user logged in on node1 and then moved to node2.

Does Apache redirect to another node when it fails to get reply from node1, How does useJk help in this situation.

---edit 01---

1. I changed the UseJK value to true but still few users still experience sudden log out which I know due to change in the server node catering the users request.
2. I also wanted to know whether traffic on the nodes has any affect on sticky session and how to counter it.( I am experiencing high load on all the servers for a few days)

----edit 02 ----

1. I would also like to know about controlling the number of connections per worker.
2. controlling the number of ajp connector/connections.
3. relation between the number of connections of apache load balancer and number of ajp connections in JBoss worker nodes.
4. what would be the best configuration between Apache 2.2.3 and JBoss 4.2.2 worker nodes with Tomcat 5.5 connectors.

---- edit03----- http://community.jboss.org/wiki/OptimalModjk12Configuration

using the above article i just wanted to know the best values for Apache MaxClients ThreadPerChild

Answer 1

I think in your worker.properties file the workerlist should have loadBalancer worker not the node1,node2 & node3.It should be like this

worker.list=loadmanager
worker.loadmanager.balance_workers=node1,node2,node3

I hope u must have these correct.

Also you have to set UserJK arttribute to set as true for load balancing with sticky session combined with JvmRoute. If set to true, it will insert a JvmRouteFilter to intercept every request and replace the JvmRoute if it detects a failover.

<attribute name="UseJK">true</attribute>

in deploy/jboss-web.deployer/META-INF/jboss-service.xml