Are Kubernetes and GNU/Linux related in any way? When Google was developing Kubernetes, did they extend, borrow from, or use any GNU/Linux concepts?
Yes, Kubernetes and GNU/Linux are related and interconnected in several ways. While Kubernetes is a container orchestration platform that can run on various operating systems, it is primarily designed to run on GNU/Linux distributions and leverages many GNU/Linux concepts and technologies.
When Google was developing Kubernetes, they built it upon many existing GNU/Linux concepts and technologies. Here are a few examples:
Containers: Kubernetes heavily relies on containerization technology, which is rooted in GNU/Linux through technologies like Linux Containers (LXC) and later Docker. Containers provide lightweight, isolated environments for running applications, and Kubernetes effectively manages and orchestrates these containers.
cgroups and namespaces: Kubernetes uses control groups (cgroups) and namespaces, which are core GNU/Linux kernel features. cgroups allow resource allocation and control, such as CPU and memory limits, while namespaces provide process isolation and namespace separation, enabling secure and isolated environments for containers.
Networking: Kubernetes networking utilizes several GNU/Linux networking concepts and technologies. It leverages the Linux kernel's networking stack, including features like IP routing, network namespaces, iptables, and IPVS (IP Virtual Server) for load balancing.
Linux kernel features: Kubernetes benefits from various features and capabilities of the Linux kernel, such as namespaces, capabilities, SELinux (Security-Enhanced Linux) for access control, and more. These features enhance security, isolation, and resource management within the Kubernetes ecosystem.
Container runtime: Kubernetes interacts with container runtimes like Docker, containerd, and CRI-O. While these runtimes are not exclusive to GNU/Linux, they are widely used on GNU/Linux distributions due to their integration with Linux-specific container technologies.
It's important to note that while Kubernetes builds upon many GNU/Linux concepts and technologies, it is designed to be platform-agnostic and can run on other operating systems as well. However, GNU/Linux distributions remain the most common and well-supported platform for running Kubernetes due to their extensive support for containerization and associated technologies.