Jay SenSharma

Jay SenSharma

Here we are going to see a WebLogic provided utility to test the Multicast Messages can flow properly in our network or not. These utilities helps us to understand whether there is any N/W issue or not …in out Network.

MultiCastMonitor Utility:

MulticastMontior is a stand-alone Java command line utility that monitors multicast traffic on a specific multicast address and port.

Below is the “MulticastMonitorTest.sh” …Please run this test as well…along with Multicast Test…


. ${WL_HOME}/common/bin/commEnv.sh


#The syntax:
#java weblogic.cluster.MulticastMonitor <multicastaddress> <port> <domainname> <clustername>

${JAVA_HOME}/bin/java -classpath ${WEBLOGIC_CLASSPATH} weblogic.cluster.MulticastMonitor ${MULTICAST_ADDRESS} ${MULTICAST_PORT} {DOMAIN_NAME}  ${CLUSTER_NAME}

Few Points regarding Multicast Address…always need to be taken care…

1). The multicast address must be an IP address between and or a hostname with an IP address in this range.
2). The default multicast address used by WebLogic Server is
3). Do not use any x.0.0.1 multicast address where x is between 0 and 9, inclusive.


: The MulticastTest utility helps you debug multicast problems when you configure a WebLogic cluster. The utility sends out multicast packets and returns information about how effectively multicast is working on your network.

Syntax: java utils.MulticastTest -n name -a address [-p portnumber]    [-t timeout]   [-s send]

Arguments Meaning
-n name Required. A name that identifies the sender of the sequenced messages. Use a different name for each test process you start.
-a address The multicast address on which: (a) the sequenced messages should be broadcast; and (b) the servers in the clusters are communicating with each other. (The default is
-p portnumber Optional. The multicast port on which all the servers in the cluster are communicating. (The multicast port is the same as the listen port set for WebLogic Server, which defaults to 7001 if unset.)
-t timeout Optional. Idle timeout, in seconds, if no multicast messages are received. If unset, the default is 600 seconds (10 minutes). If a timeout is exceeded, a positive confirmation of the timeout is sent to stdout.
-s send Optional. Interval, in seconds, between sends. If unset, the default is 2 seconds. A positive confirmation of each message sent out is sent to stdout.

Always Remember:

Do NOT run the MulticastTest utility by specifying the same multicast address (the -a parameter) as that of a currently running WebLogic Cluster. The utility is intended to verify that multicast is functioning properly in out network or not….So basically it is a N/W related utility. Ususlly this should be done before starting your clustered WebLogic Servers or when we face Multicast related issues in server logs.

Set Cluser Debugs Using weblogic.Admin utility:

java weblogic.Admin -url t3://localhost:7001 – username weblogic -password weblogic SET -type ServerDebug -property DebugCluster true

Jay SenSharma

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