3.4. Deploying Composite Multimaster Clustering

A Composite Multimaster Cluster topology provides all the benefits of a typical dataservice at a single location, but with the benefit of also replicating the information to another site. The underlying configuration within Tungsten Cluster uses two services within each node; one provides the replication within the cluster, and the second provides replication from the remote cluster. Both are managed by the Tungsten Manager

Note

Multimaster Clusters were previously referred to as Multisite/Multimaster clusters. The name has been updated to reflect the nature of these clusters as part of an overall multimaster deployment using clusters, where the individual clusters could be in the same or different locations.

Whilst the older Multisite/Multimaster topology is still valid and supported, it is recommended that this newer Composite Multimaster topology is adopted from version 6 of Tungsten Cluster onwards. For details on the older topology, see Section 3.3, “Deploying Multisite/Multimaster Clustering”

The configuration is handled with a single configuration and deployment that configures the core cluster services and additional cross-cluster services.

A sample display of how this operates is provided in Figure 3.4, “Topologies: Composite Multimaster Clusters”.

Figure 3.4. Topologies: Composite Multimaster Clusters

Topologies: Composite Multimaster Clusters

The service can be described as follows:

  • Tungsten Cluster Service: east

    Replicates data between east1, east2 and east3 (not shown).

  • Tungsten Cluster Service: west

    Replicates data between west1, west2 and west3 (not shown).

  • Tungsten Cluster Service: west_from_east

    Defines the replication of data within east as a replicator service using a secondary service within the cluster deployed Tungsten Replicator. This service reads from all the hosts within the Tungsten Cluster service east and writes to west1, west2, and west3.

  • Tungsten Replicator Service: east_from_west

    Defines the replication of data within west as a replicator service using a secondary service within the cluster deployed Tungsten Replicator. This service reads from all the hosts within the Tungsten Cluster service west and writes to east1, east2, and east3.