This section provides information about nodes and clusters in API Gateway and how to configure an API Gateway cluster after you have installed the product. For installation procedures for the product, see Installing IBM webMethods Products On Premises.

API Gateway supports clustering to achieve horizontal scalability and reliability.

Each API Gateway cluster node holds all the API Gateway components including API Gateway user interface, the API Gateway package running in IBM webMethods Integration Server, and an external Elasticsearch instance for storing assets. The external Elasticsearch is either embedded in the API Gateway instance or the API Gateway instances store there assets in a separate or external Elasticsearch cluster. A load balancer distributes the incoming requests to the cluster nodes. You can synchronize the nodes through Apache Ignite.

As each node of an API Gateway cluster offers the same functionality, nodes can be added or removed from an existing cluster. The synchronization of any new node happens automatically. The synchronization includes configuration items, and runtime assets like APIs, policies, and applications. The synchronized runtime assets become active automatically.

You can cluster API Gateway nodes using the Apache Ignite cluster coordinator.

API Gateway cluster can also be deployed as a traditional on-premise installation on real or virtual machines, as Docker containers, or in Kubernetes clusters.

This setup depicts a peer to peer clustered environment using Apache Ignite and external Elasticsearch clustering that is defined across the external Elasticsearch instances. In this setup, Apache Ignite runs embedded inside each API Gateway instance and is used for distributed caching.