Failover

Failover ensures high availability by routing traffic to healthy backends when primary backends become unavailable.

Primary/Fallback Configuration

Define multiple backends with priorities:

backends:
  - name: "primary"
    url: "http://api-primary.default.svc.cluster.local:8080"
    weight: 100
  - name: "fallback"
    url: "http://api-fallback.default.svc.cluster.local:8080"
    weight: 0

Health Checks for Automatic Failover

Enable health checks to automatically detect and remove unhealthy backends:

defaultTrafficPolicy:
  healthCheck:
    active:
      type: "HTTP"
      http:
        path: "/health"
        expectedStatuses:
          - 200
      interval: "10s"
      timeout: "5s"
      unhealthyThreshold: 3
      healthyThreshold: 2

How Failover Works

1. Health checks run at configured intervals
2. Backend marked unhealthy after unhealthyThreshold failures
3. Traffic automatically routes to healthy backends
4. Backend restored after healthyThreshold successes

Combine with circuit breakers for comprehensive resilience.