We have a cluster Tomcat composed of two servers (default configuration of
the cluster is used).
When the first server is stopped, the cluster continues to work fine
(requests are handled by the server that is running).
But when the stopped server is restarting we can see these exceptions.
Could you comment this log and explain us what is wrong. Thanks.
The server that handle the requests log this exception
Server 02
10 nov. 2004 17:13:54 org.apache.catalina.cluster.tcp.SimpleTcpCluster
memberAdded
INFO: Replication member
added:org.apache.catalina.cluster.mcast.McastMember[tcp://w.x.y.z:41001,w.x.
y.z,41001, alive=35]
10 nov. 2004 17:13:54 org.apache.catalina.cluster.session.DeltaManager
messageReceived
GRAVE: Unable to receive message through TCP channel
java.lang.NullPointerException
at
java.io.ObjectOutputStream$BlockDataOutputStream.getUTFLength(ObjectOutputSt
ream.java:1898)
at
java.io.ObjectOutputStream$BlockDataOutputStream.writeUTF(ObjectOutputStream
.java:1769)
at java.io.ObjectOutputStream.writeUTF(ObjectOutputStream.java:787)
at
org.apache.catalina.cluster.session.SerializablePrincipal.writePrincipal(Ser
ializablePrincipal.java:180)
at
org.apache.catalina.cluster.session.DeltaSession.writeObject(DeltaSession.ja
va:1457)
at
org.apache.catalina.cluster.session.DeltaSession.writeObjectData(DeltaSessio
n.java:930)
at
org.apache.catalina.cluster.session.DeltaManager.doUnload(DeltaManager.java:
539)
at
org.apache.catalina.cluster.session.DeltaManager.messageReceived(DeltaManage
r.java:854)
at
org.apache.catalina.cluster.session.DeltaManager.messageDataReceived(DeltaMa
nager.java:762)
at
org.apache.catalina.cluster.tcp.SimpleTcpCluster.messageDataReceived(SimpleT
cpCluster.java:576)
at
org.apache.catalina.cluster.io.ObjectReader.execute(ObjectReader.java:70)
at
org.apache.catalina.cluster.tcp.TcpReplicationThread.drainChannel(TcpReplica
tionThread.java:129)
at
org.apache.catalina.cluster.tcp.TcpReplicationThread.run(TcpReplicationThrea
d.java:67)
In the same time the server restarting logs this information.
server 01
Creating ClusterManager for context /myapp using class
org.apache.catalina.cluster.session.DeltaManager
10 nov. 2004 17:13:54 org.apache.catalina.cluster.session.DeltaManager start
INFO: Starting clustering manager...:/myapp
10 nov. 2004 17:13:54 org.apache.catalina.cluster.session.DeltaManager start
ATTENTION: Manager[/myapp], requesting session state from
org.apache.catalina.cluster.mcast.McastMember[tcp://w.x.y.z:42001,w.x.y.z,42
001, alive=111640]. This operation will timeout if no session state has been
received within 60 seconds
After a delay, server 01 logs this information.
10 nov. 2004 17:14:54 org.apache.catalina.cluster.session.DeltaManager start
GRAVE: Manager[/myapp], No session state received, timing out.
10 nov. 2004 17:14:54 org.apache.catalina.core.StandardHostDeployer install
INFO: Installation d'une application pour le chemin de contexte depuis
l'URL file:/opt/tomcat-tst01/webapps/ROOT
...
INFO: Server startup in 62980 ms
server 01 handle the application requests, new session is created.
