Load balancer

This policy balances incoming requests among backend endpoints to improve performance and reliability.

Through Load balancer policy, requests are routed based on the round-robin strategy and distributed across multiple endpoints.

The load for a service is balanced by directing requests to two or more services in a pool until the optimum level is achieved. The application routes requests to services in the pool sequentially, starting from the first and moving to the last, without considering the individual performance of the services.

After all services in the pool have received requests, the first service is chosen again, and the cycle repeats.

In IBM API Studio, this policy is identified by the kind LoadBalancer.

Example of a Load balanced routing policy:

kind: LoadBalancer
apiVersion: apim.ibm.com/v1
metadata:
  name: loadbalancer-routing
  version: 1.0
  namespace: dev
  tags:
    - routing
    - route
    - policy
spec:
  input : request # optional 
  output : response # optional
  roundRobinHttp:
    verb: "GET"
    endpoints:
      - endpoint:
          name: 'endpoint_1'
          tlsClientProfile: tls_profile
          url: ${pet_url_alias}  
          urlType: 'plain' # plain, variables, jsonata      
          version: HTTP/1.0 # HTTP/1.1, HTTP/2
          timeout: 200
          compressRequest: "br" # "gzip", "br", "deflate", "none"
          decompressResponse: false
          followRedirects: false
          chunkedUpload: false
          persistentConnections: true
        suspendTimeout: 300
    statusException:
      - pattern: '200'
  extensions:
    webm-gateway:
      apiVersion: api.ibm.com/v1
      spec:
        endpoints:
          - name: 'endpoint_1'
            connectionTimeout: 300
            sslConfig:
              keyStoreAlias: DEFAULT_IS_KEYSTORE
              keyAlias: ssos
              trustStoreAlias: DEFAULT_IS_TRUSTSTORE
            serviceRegistryParameters:
              - name: ""
                value: ""

To invoke the Load balancer policy, you can specify the following configurations: