A Sysdig + Kubernetes adventure, Part 1: How Kubernetes services work

In this first part of a two-part series, Gianluca Borello delves into the workings of Kubernetes services using the open-source tool Sysdig. Borello explains that a Kubernetes service acts as an abstraction layer that provides a single entry point for accessing a group of pods, functioning like a dynamic load balancer. This simplifies application development by eliminating the need for manual service discovery mechanisms. He sets up a simple Kubernetes environment with two nginx pods and a service, demonstrating how these services use DNS extensions to map service names to virtual IPs, allowing transparent access by other pods. The article explores the technical intricacies of how Kubernetes handles DNS requests and routes them through a virtual IP using Linux kernel Netfilter capabilities, ensuring stable service discovery even if pods change locations. Borello highlights how Sysdig can capture and analyze network events to illustrate these processes, setting the stage for troubleshooting in more complex or faulty environments in the upcoming second part.