Tomcat session replication - different machines configuration

Question

If i want to create a cluster of 2 tomcats:

Tomcat1 - ip 111.111.111.111 Tomcat2 - ip 222.222.222.222

Where exactly the in the server.xml i should say that my cluster contains both of these ips? If you will take alook at my server.xml (which i copy pasted from the tutorial) it looks like this:

<?xml version='1.0' encoding='utf-8'?>

<Server port="8105" shutdown="SHUTDOWN">

<GlobalNamingResources>

<Resource name="UserDatabase" auth="Container"
          type="org.apache.catalina.UserDatabase"
          description="User database that can be updated and saved"
          factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
          pathname="conf/tomcat-users.xml" />
 </GlobalNamingResources>
  <Service name="Catalina">


<Connector port="8080" protocol="HTTP/1.1"
           connectionTimeout="20000"
           redirectPort="8443" />

<Connector port="8109" protocol="AJP/1.3" redirectPort="8443" />


<Engine name="Catalina" defaultHost="localhost">
<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster">
  <Manager className="org.apache.catalina.ha.session.BackupManager"
               expireSessionsOnShutdown="false"
               notifyListenersOnReplication="true"
               mapSendOptions="6"/>   
   </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 &quot;%r&quot; %s %b" />

    </Host>
   </Engine>
  </Service>
</Server>

Answer 1

Cluster nodes are discovered using UDP multicast by default, therefore an explicit host list is not required in this example.

If your target environment doesn't support UDP multicast , then you'll have to switch to static membership :

<Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster">

   <Manager className="org.apache.catalina.ha.session.DeltaManager"
            expireSessionsOnShutdown="false"
            notifyListenersOnReplication="true"/>

   <!-- Membership config (Tomcat1) -->
   <Channel className="org.apache.catalina.tribes.group.GroupChannel">
            <Receiver className="org.apache.catalina.tribes.transport.nio.NioReceiver"
                      address="auto"
                      port="4000"
                      autoBind="100"
                      selectorTimeout="5000"
                      maxThreads="6"/>

            <Sender className="org.apache.catalina.tribes.transport.ReplicationTransmitter">
              <Transport className="org.apache.catalina.tribes.transport.nio.PooledParallelSender"/>
            </Sender>

            <Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor"/>
            <Interceptor className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector"/>
            <Interceptor className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor"/>

            <!-- Setup static members below -->
            <Interceptor className="org.apache.catalina.tribes.group.interceptors.StaticMembershipInterceptor">
                <!-- Commented out on Tomcat1
                <Member className="org.apache.catalina.tribes.membership.StaticMember"
                        port="4100"
                        host="111.111.111.111"
                        domain="delta-static"
                        uniqueId="{0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}"
                />
                -->                    
                <Member className="org.apache.catalina.tribes.membership.StaticMember"
                        port="4100"
                        host="222.222.222.222"
                        domain="delta-static"
                        uniqueId="{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,0}"
                />
            </Interceptor>
   </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>