Weblogic Cluster and cluster communication amongst manager servers

I was under the impression that ALL the communication amongst MS (managed servers) in the same cluster would occur via MULTICAST or UNICAST. This would include:

- HTTPSession synchronization - if Session Replication is enabled

- JNDI tree synchronization

- Health state monitoring

In reality most of these communication occurs with TCP-IP Sockets!

Setting Debug Flags on the Command Line

Set these flags from the command line during server startup by adding the following options:

-Dweblogic.debug.DebugCluster=true

-Dweblogic.debug.DebugClusterHeartBeats=true

-Dweblogic.debug.DebugClusterFragments=true

these flags should be available on the ServerDebugMBean.

in WLST, find('DebugCluster') should point you to the right place:


/Servers/yourServerName/ServerDebug/yourServerName DebugClusterHeartbeats
/Servers/yourServerName/ServerDebug/yourServerName DebugClusterAnnouncements
/Servers/yourServerName/ServerDebug/yourServerName DebugCluster
/Servers/yourServerName/ServerDebug/yourServerName DebugClusterFragments


so somethig like:

connect(......)
edit()
startEdit()
cd('/Servers/yourServerName/ServerDebug/yourServerName')
cmo.setDebugClusterHeartbeats(true)
cmo.setDebugClusterAnnouncements(true)
cmo.setDebugCluster(true)
cmo.setDebugClusterFragments (true)

save()
activate()


should do

you should see at this point messages in the log file, such as:

ClusterHeartbeats ... Sent Heartbeat with 1 items

ClusterHeartbeats ... Received Heartbeat with 1 items from 5446592690916645012S:bcdev07.server.ux.nuon.local:[5420,5420,-1,-1,-1,-1,-1]:bcdev07.server.ux.nuon.local:5410,bcdev07.server.ux.nuon.local:5420:prx_eb_alsb_dev:prx_eb_alsb_dev_server_2

ClusterAnnouncements ... Sending local attributes prx_eb_alsb_dev_server_1 jvmid:753244874926136889S:bcdev07.server.ux.nuon.local:bcdev07.server.ux.nuon.local:5410,bcdev07.server.ux.nuon.local:5420:prx_eb_alsb_dev:prx_eb_alsb_dev_server_1

Cluster .... Sending senderNum:1 seqNum:0 message:Attributes prx_eb_alsb_dev_server_1 jvmid:753244874926136889S:bcdev07.server.ux.nuon.local:bcdev07.server.ux.nuon.local:5410,bcdev07.server.ux.nuon.local:5420:prx_eb_alsb_dev:prx_eb_alsb_dev_server_1 outgoing message:message:[115, 114,


ClusterFragments .... Sending fragment senderNum:1 seqNum:0fragNum:0 containing 1067 bytes out of 2375

ClusterFragments .... Sending fragment senderNum:1 seqNum:0fragNum:1 containing 1067 bytes out of 2375

ClusterFragments .... Sending fragment senderNum:1 seqNum:0fragNum:2 containing 241 bytes out of 2375