Hello,
I'm setting up clustering/replication on Tomcat 7 on my local machine, to
evaluate it for use with my environment/codebase, and sessions don't appear
to be replicating. Hopefully I've provided enough information below, but
please let me know if you have any more questions.
___Setup___
I have two identical tomcat servers in sibling directories running on
different ports. I have httpd listening on two other ports and connecting
to the two tomcat instances as VirtualHosts. I can access and interact with
both environments on the configured ports; everything is working as
expected.
The tomcat servers have clustering enabled like this, in server.xml:
<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="45564"
frequency="500"
dropTime="3000"/>
<Receiver
className="org.apache.catalina.tribes.transport.nio.NioReceiver"
address="auto"
port="4001"
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.TcpFailureDetector"/>
<Interceptor
className="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor"/>
<Interceptor
className="org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor"/>
</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.ClusterSessionListener"/>
</Cluster>
and I added the distributable tag to the very beginning of web.xml:
<web-app xmlns="http://java.sun.com/xml/ns/javaee";
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd";
version="3.0">
<distributable />
(lots more...)
</web-app>
___What's working___
When the servers start, they log
Sep 16, 2013 1:44:23 PM org.apache.catalina.ha.tcp.SimpleTcpCluster
startInternal
INFO: Cluster is about to start
Sep 16, 2013 1:44:23 PM org.apache.catalina.tribes.transport.ReceiverBase
getBind
FINE: Starting replication listener on address:10.0.0.100
Sep 16, 2013 1:44:23 PM org.apache.catalina.tribes.transport.ReceiverBase
bind
INFO: Receiver Server Socket bound to:/10.0.0.100:4001
Sep 16, 2013 1:44:23 PM
org.apache.catalina.tribes.membership.McastServiceImpl setupSocket
INFO: Setting cluster mcast soTimeout to 500
Sep 16, 2013 1:44:23 PM
org.apache.catalina.tribes.membership.McastServiceImpl waitForMembers
INFO: Sleeping for 1000 milliseconds to establish cluster membership, start
level:4
Sep 16, 2013 1:44:24 PM
org.apache.catalina.tribes.membership.McastServiceImpl waitForMembers
INFO: Done sleeping, membership established, start level:4
Sep 16, 2013 1:44:24 PM
org.apache.catalina.tribes.membership.McastServiceImpl waitForMembers
INFO: Sleeping for 1000 milliseconds to establish cluster membership, start
level:8
Sep 16, 2013 1:44:25 PM
org.apache.catalina.tribes.membership.McastServiceImpl waitForMembers
INFO: Done sleeping, membership established, start level:8
When the second server starts up, the first one logs
Sep 16, 2013 2:17:30 PM
org.apache.catalina.tribes.group.interceptors.TcpFailureDetector
messageReceived
FINE: Received a failure detector
packet:ClusterData[src=org.apache.catalina.tribes.membership.MemberImpl[tcp://{10,
0, 0, 100}:4000,{10, 0, 0, 100},4000, alive=112208, securePort=-1, UDP
Port=-1, id={118 6 107 -67 88 98 72 95 -73 41 4 -108 58 -5 -127 -41 },
payload={}, command={}, domain={}, ]; id={25 110 120 -2 -25 6 78 -97 -84
-34 2 -11 49 -62 -8 -56 }; sent=2013-09-16 14:17:30.139]
Sep 16, 2013 2:17:30 PM
org.apache.catalina.tribes.transport.nio.NioReplicationTask remoteEof
FINE: Channel closed on the remote end, disconnecting
Sep 16, 2013 2:17:30 PM
org.apache.catalina.tribes.membership.McastServiceImpl memberDataReceived
FINE: Mcast add member
org.apache.catalina.tribes.membership.MemberImpl[tcp://{10, 0, 0,
100}:4001,{10, 0, 0, 100},4001, alive=1010, securePort=-1, UDP Port=-1,
id={82 -45 -109 -56 -110 -5 78 -10 -103 61 -40 -59 -36 -79 104 120 },
payload={}, command={}, domain={}, ]
Sep 16, 2013 2:17:30 PM org.apache.catalina.ha.tcp.SimpleTcpCluster
memberAdded
INFO: Replication member
added:org.apache.catalina.tribes.membership.MemberImpl[tcp://{10, 0, 0,
100}:4001,{10, 0, 0, 100},4001, alive=1011, securePort=-1, UDP Port=-1,
id={82 -45 -109 -56 -110 -5 78 -10 -103 61 -40 -59 -36 -79 104 120 },
payload={}, command={}, domain={}, ]
and when one is shutdown, the other one logs
Sep 16, 2013 2:28:05 PM
org.apache.catalina.tribes.membership.McastServiceImpl memberDataReceived
FINE: Member has
shutdown:org.apache.catalina.tribes.membership.MemberImpl[tcp://{10, 0, 0,
100}:4001,{10, 0, 0, 100},4001, alive=422279, securePort=-1, UDP Port=-1,
id={54 43 17 -9 13 -11 72 -63 -107 -78 -8 65 -21 -77 115 88 }, payload={},
command={66 65 66 89 45 65 76 69 88 ...(9)}, domain={}, ]
Sep 16, 2013 2:28:05 PM
org.apache.catalina.tribes.group.interceptors.TcpFailureDetector
memberDisappeared
INFO: Verification complete. Member
disappeared[org.apache.catalina.tribes.membership.MemberImpl[tcp://{10, 0,
0, 100}:4001,{10, 0, 0, 100},4001, alive=422279, securePort=-1, UDP
Port=-1, id={54 43 17 -9 13 -11 72 -63 -107 -78 -8 65 -21 -77 115 88 },
payload={}, command={66 65 66 89 45 65 76 69 88 ...(9)}, domain={}, ]]
Sep 16, 2013 2:28:05 PM org.apache.catalina.ha.tcp.SimpleTcpCluster
memberDisappeared
INFO: Received member
disappeared:org.apache.catalina.tribes.membership.MemberImpl[tcp://{10, 0,
0, 100}:4001,{10, 0, 0, 100},4001, alive=422279, securePort=-1, UDP
Port=-1, id={54 43 17 -9 13 -11 72 -63 -107 -78 -8 65 -21 -77 115 88 },
payload={}, command={66 65 66 89 45 65 76 69 88 ...(9)}, domain={}, ]
so I know they're aware of each other.
Finally, when I use the Cluster/Operations MBean in jconsole to try to set
property "foo" to "bar", jconsole reports "method successfully invoked",
and the server logs
Sep 16, 2013 2:30:18 PM org.apache.catalina.ha.tcp.SimpleTcpCluster
setProperty
WARNING: Dynamic setProperty(foo,value) has been disabled, please use
explicit properties for the element you are trying to identify
I'm not too worried about that error; mostly included to demonstrate that
setProperty creates a log statement.
___What's not working___
As far as I can tell, no session information is being replicated in my app.
The tomcat manager only lists sessions started on the server it's
monitoring, and not the other one in the cluster.
I'm under the impression that whenever the app calls
HttpSession.setAttribute, that attribute should be replicated to the other
cluster nodes, and I would expect that some record of that would be logged.
My app includes this line:
public static void saveBillingInfo(IPageContext pageContext, BillingInfo
billingInfo)
{
pageContext.getSession().setAttribute("billingInfo", billingInfo);
//etc...
}
where BillingInfo is a Serializable class containing only one field, a
HashMap of information about the billing info.
No log statements are written when this or any other line processes, and I
don't see any evidence that session information is actually being shared.
Any suggestions or further questions are welcome. Thanks in advance!
