Envoy vs Kubernetes: What are the differences?

Introduction

In this article, we will compare and highlight the key differences between Envoy and Kubernetes, two popular technologies in the world of containerization and microservices.

1. Networking Model: Envoy is primarily a high-performance, extensible proxy server that enables efficient and secure communication between services within a network. It focuses on providing advanced traffic management capabilities, such as load balancing, circuit breaking, and observability. On the other hand, Kubernetes is a container orchestration platform that takes care of container deployments, scaling, and management across a cluster of nodes. While Kubernetes also offers built-in load balancing, it does not offer the same level of advanced networking features as Envoy.

2. Deployment Flexibility: Kubernetes allows you to deploy and manage various types of applications, not just microservices, making it a more versatile and general-purpose solution. It provides powerful deployment mechanisms such as rolling updates, canary deployments, and automatic scaling based on resource utilization. Envoy, on the other hand, is specifically designed for microservices architectures and excels at handling east-west traffic between services within a network. It is often used as a sidecar proxy alongside application containers, adding an extra layer of functionality and control.

3. Configuration Language: Envoy has its own declarative configuration language called Configuration Discovery Service (CDS). It allows you to define the behavior of the proxy server and its interaction with other services using a JSON or YAML-based syntax. Kubernetes, on the other hand, uses YAML files to define the desired state of applications, including containers, volumes, and networking. YAML is more widely adopted and easier to work with for developers familiar with Kubernetes.

4. Service Discovery: Kubernetes includes a built-in service discovery and DNS system that automatically assigns and resolves IP addresses to services within the cluster. This enables easy and dynamic inter-service communication. Envoy also supports service discovery, but it provides additional features like intelligent load balancing and health checking. Envoy can integrate with various service discovery mechanisms, including Kubernetes' own service discovery, to provide enhanced capabilities.

5. Observability and Monitoring: Envoy offers powerful built-in observability features, including detailed logging, distributed tracing, and metrics collection. It integrates seamlessly with popular observability tools like Prometheus, Grafana, and Jaeger. Kubernetes also provides monitoring capabilities through its built-in metrics server, but it may require additional tooling and configuration to achieve the same level of observability as Envoy.

6. Platform Maturity: Kubernetes is a mature platform with a large community and ecosystem. It has been widely adopted and is backed by major cloud providers, making it a reliable choice for production deployments. Envoy, although it has gained significant traction and popularity, is a relatively newer technology compared to Kubernetes. While it has a growing community and active development, it may not have the same level of maturity or industry support as Kubernetes.

In summary, Envoy is a high-performance proxy server with advanced networking capabilities, specifically designed for microservices architectures. Kubernetes, on the other hand, is a container orchestration platform that provides deployment and management features for various types of applications, with built-in networking capabilities. The choice between Envoy and Kubernetes depends on the specific requirements and nature of the applications or environments they are being used in.