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WebLogic Server (WLS) Multicast Issues Support Pattern (Doc ID 1092037.1)

Last updated on APRIL 03, 2024

Applies to:

Oracle WebLogic Server - Version 6.1 and later
Information in this document applies to any platform.


This document describes how to resolve problems associated with Multicast communication.

Problem Description

A WebLogic Server instance has problems listening to, receiving messages on, or being generally successful using multicast with Oracle WebLogic Server.

In WebLogic Server 10.0 and higher, Oracle recommends that you use unicast communication rather than multicast for communication within a cluster. Multicast should be used to maintain backward compatibility with earlier releases of WebLogic Server. See Communications in a Cluster for more details. This support pattern focuses only on multicast issues.

Problem Troubleshooting

Please note that not all of the following items would need to be done. Some issues can be solved by only following a few of the items.

Troubleshooting Steps

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In this Document
 Problem Description
 Problem Troubleshooting
Troubleshooting Steps
 Why does the problem occur?
 Multicast address/port issues
 Physical problems/issues sharing address
 Duplicate IP addresses
 Testing multicast / erroneous communications
 File descriptor issues
 Nsswitch configuration
 Multicast timeouts
 Cluster heartbeat problems
 Cluster multicast storm issues
 Example scenario:
 Background on multicast storms
 Configure multicast buffer size
 Multihoming configuration
 AIX-specific issues
 Background information
 Debugging multicast
 Debugging flags
 Debug multicast
 Need further help?

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