Hands-On Microservices with Kubernetes

Load balancing

Istio has its own platform-independent service discovery with adapters for the underlying platform (for example, Kubernetes). It relies on the existence of a service registry that the underlying platform manages, and removes unhealthy instances in order to update its load balancing pools. There are currently three supported load balancing algorithms:

• Round robin
• Random
• Weighted least request

Envoy has a few more algorithms, such as Maglev, ring hash, and weighted round robin, that Istio doesn't support yet.

Istio also performs periodic health checks to verify that instances in the pool are actually healthy, and can remove them from load balancing temporarily if they fail the configured health check threshold.

You can configure ...