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Troubleshooting Guide for TMB Connection Issues in the 12.2.1.x.x Coherence Clusters and FMW Domains (Doc ID 2380907.1)

Last updated on NOVEMBER 08, 2021

Applies to:

Oracle Coherence - Version and later
Information in this document applies to any platform.


This document helps to verify the tmb:// configurations of the cluster, connectivity test between the machines of the cluster, patch validation and collect additional data to diagnose the problem.

TCMP is an IP-based protocol that is used to discover cluster members, manage the cluster, provision services, and transmit data.

TCMP for cluster service communication can be configured to use TCP/IP, SDP/IP or UDP/IP - A combination of UDP/IP multicast and UDP/IP unicast is the default cluster protocol for cluster service communication. Cluster Service is automatically started when a cluster node must join the cluster and is often referred to as the root cluster service; each cluster node always has exactly one service of this type running. This service is responsible for the detection of other cluster nodes, for detecting the failure of a cluster node, and for registering the availability of other services in the cluster.

TCMP for data service [Distributed Cache, Federated Cache, Replicated Cache and Optimistic Cache] communication is configurable to use a reliable transport, [datagram, tmb(s), sdmb(s) and imb]. In the 12.2.1.x.x, versions default tmb:// is default for non-Exalogic platforms. TMB specifies the TCP Message Bus (TMB) protocol. TMB provides support for TCP/IP. TCP/IP message bus protocol with SSL support is tmbs://. TMBS requires the use of an SSL socket provider. Use of TCP in the Coherence Cluster, TCMP uses a shared TCP/IP Message Bus (TMB) for data transfers. The TCMP protocol (as configured by default) requires only three sockets (one multicast, two unicast) and six threads per JVM, regardless of the cluster size. For TCMP/TMB, which is the default protocol for point-to-point data communication, each cluster member binds to a single port.

Troubleshooting Steps

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In this Document
Troubleshooting Steps
 How to set and verify the reliable transport protocol tmb:// or tmbs://?
 Are any specific TCP Considerations required?
 How to test tmb:// or tmbs:// is working between the machines?
 Additional Logging and Tracing:

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