Team Concert 6.0.4: New Horizontal Clustering Features

Off
Strongback Consulting

CLM Clustering is Dead!

 Anyone who has worked on WebSphere App server certainly should be familiar with the deployment manager and cluster typologies. One would have thought that since RTC is a Java application, that the native WAS clustering would be a perfect fit. Unfortunately, it was not. Team concert ended support for horizontal clustering on WebSphere App Server with version 5 of the product. It had been very cumbersome and problematic to maintain. One IBM product expert I spoke with said that at the time, it was much easier to just use a load balancer with operating system clusters, just as Microsoft’s cluster services.

Long Live CLM Clustering!

Likely due to customer demand, IBM has reintroduced support for Java based clustering with CLM 6.0.4. This is an entirely new type of Java clustering because it is supported only on WebSphere Liberty (not WAS traditional or ND). Under the covers, the magic that makes this happen is a MQTT broker which manages cache invalidation and coordination messages, which was the Achilles heel of the old method of clustering. The MQTT Broker is not included as a part of the solution and would need to be purchased separately. There is also an available open source broker, http://mosquitto.org/.

MQTT Brokering

MQTT (Message Queue Telemetry Transport) is a machine to machine protocol designed for IoT applications. It is designed as a lightweight publish/subscribe messaging protocol, and is an OASIS standard. This standard is implemented by vendor products such as IBM IoT MessageSight, which is a standalone appliance separate from Team Concert / CLM. Here’s an overview of MessageSight and how it works:

You might also be interested in the technical details of MQTT protocol by :

Link to the new features in RTC announcements:

Comments are closed.