Apache/Tomcat setup:
Apache
|
/ \
/ \
C1 C2 Clusters
| |
/ \ / \
/ \ / \
T1 T2 T3 T4 Tomcats
- Windows Server 2012
- Apache 2.2.25
- mod_jk 1.2.20
- Tomcat 7.0.42
I have load balancing on C1 and C2. T1 and T2 are a group and T3 and T4 are another group. C1 and C2 are independant.
workers.properties:
worker.list=jkstatus,Cluster1,Cluster2,C1T1,C1T2,C2T1,C2T2
worker.jkstatus.type=status
# Configuration Cluster 1
worker.Cluster1.type=lb
worker.Cluster1.balance_workers=C1T1,C1T2
worker.C1T1.port=8119
worker.C1T1.host=localhost
worker.C1T1.type=ajp13
worker.C1T1.lbfactor=1
worker.C1T1.redirect=C1T2
worker.C1T2.port=8129
worker.C1T2.host=localhost
worker.C1T2.type=ajp13
worker.C1T2.lbfactor=1
worker.C1T2.redirect=C1T1
# Configuration Cluster 2
worker.Cluster2.type=lb
worker.Cluster2.balance_workers=C2T1,C2T2
worker.C2T1.port=8219
worker.C2T1.host=localhost
worker.C2T1.type=ajp13
worker.C2T1.lbfactor=1
worker.C2T1.redirect=C2T2
worker.C2T2.port=8229
worker.C2T2.host=localhost
worker.C2T2.type=ajp13
worker.C2T2.lbfactor=1
worker.C2T2.redirect=C2T1
Apache redirect every requests either to Cluster1 or Cluster2 this way:
JkMount /MyApp/* Cluster1
server.xml:
<Engine name="Catalina" defaultHost="localhost" jvmRoute="C1T1">
<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster" channelSendOptions="8">
<Manager className="org.apache.catalina.ha.session.DeltaManager" expireSessionsOnShutdown="false" notifyListenersOnReplication="true"/>
<Channel className="org.apache.catalina.tribes.group.GroupChannel">
<Membership className="org.apache.catalina.tribes.membership.McastService" address="228.0.0.4" port="45562" frequency="500" dropTime="3000"/>
<Sender className="org.apache.catalina.tribes.transport.ReplicationTransmitter">
<Transport className="org.apache.catalina.tribes.transport.nio.PooledParallelSender"/>
</Sender>
<Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver" address="auto" port="4001" autoBind="100" selectorTimeout="5000" maxThreads="6"/>
<Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector"/>
<Interceptor className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor"/>
</Channel>
<Valve className="org.apache.catalina.ha.tcp.ReplicationValve" filter=""/>
<Valve className="org.apache.catalina.ha.session.JvmRouteBinderValve"/>
<ClusterListener className="org.apache.catalina.ha.session.JvmRouteSessionIDBinderListener"/>
<ClusterListener className="org.apache.catalina.ha.session.ClusterSessionListener"/>
</Cluster>
<Realm className="org.apache.catalina.realm.LockOutRealm">
<Realm className="org.apache.catalina.realm.UserDatabaseRealm" resourceName="UserDatabase"/>
</Realm>
<Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true">
<Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs" prefix="localhost_access_log." suffix=".txt" pattern="%h %l %u %t "%r" %s %b" />
</Host>
</Engine>
T1/T2 have the same address/port and T3/T4 have the same address/port (different from T1/T2).
I followed this: http://tomcat.apache.org/tomcat-7.0-doc/cluster-howto.html and this: http://tomcat.apache.org/connectors-doc/reference/workers.html
Load balacing works fine. If I shut down one Tomcat on a Cluster, Apache redirect all requests to the other Tomcat. Sessions are replicated too (I used JConsole to track the number of active sessions on both Tomcat).
Now, here is my problem:
Every time I hit F5 a new session is created (I use @SessionBean
on Tomcat). If I bypass the cluster by accessing directly the Tomcat with its HTTP port, a new session is created, but no new sessions are created when I hit F5.
I would like to know why when accessed with Apache, a new session is created on every request (and how to fix it!).
Finally figured it out.
Clustering did not cause this. It was the JSESSIONID cookie of JSF: its path was
/MyApp/
instead of/
(apache forward/
to/MyApp/
).EDIT: Had to set
sessionCookiePath="/"
on the<Context ...></Context>
file of the tomcats (conf/context.xml
) like this: