What is Load Balancing in Spring Cloud and how does Spring Cloud LoadBalancer work? स्प्रिंग क्लाउड में लोड बैलेंसिंग क्या है और Spring Cloud LoadBalancer कैसे काम करता है?

When a service has multiple running instances for scalability and fault tolerance, calls to it need to be distributed across those instances rather than always hitting one. Client-side load balancing resolves the service name (from Eureka) to a specific instance address at call time, choosing among healthy instances using a strategy like round-robin.

Spring Cloud LoadBalancer is the current standard (replacing the deprecated Netflix Ribbon), integrated transparently with RestTemplate (via @LoadBalanced), WebClient, and Feign — application code calls the logical service name, and the load balancer picks and routes to a healthy instance behind the scenes.

@Bean
@LoadBalanced
public RestTemplate restTemplate() {
    return new RestTemplate();
}

restTemplate.getForObject("http://ORDER-SERVICE/api/orders/1", Order.class);