15.2. Setting Up SwitchYard in a Clustered Environment
The two fundamental building blocks that are used for setting up SwitchYard in a clustered environment are:
- Shared Runtime Registry: A shared, distributed runtime registry that enable individual instances to publish and query service endpoint details.
- Remote Communication Channels: An internal communication protocol that enables a service client to invoke a service, hosted in a remote instance.
The runtime registry supports a replicated Infinispan cache. Each instance in a cluster points to the same replicated cache. When a node joins a cluster, it immediately has access to all remote service endpoints published in the registry. If a node leaves the cluster due to failure or shutdown, all service endpoint registrations are immediately removed for that node. The registry is not persisted, so manual clean-up and maintenance is not required.
The communication channel is a private intra-cluster protocol used by instances to invoke a remote service. At present, the channel is based on HTTP.
Note
The SwitchYard registry is a runtime registry and not a publication registry. The state of services within the registry is tied directly to the current state of services deployed within a cluster.
