Docker Architecture and Container Operations Crash Course
Unlike traditional Type-1 and Type-2 hypervisors that virtualize complete hardware stacks and boot independent operating system kernels, containers share the host Linux kernel while isolating processes using kernel Namespaces (PID, NET, IPC, MNT, UTS) and Control Groups (cgroups). Docker packages application dependencies, libraries, and runtime binaries into lightweight, immutable container images. Core Architecture Docker operates under a client-server model: Docker Client (docker): The CLI tool you execute to issue commands. Docker Daemon (dockerd): The background daemon listening for API requests to manage images, containers, networks, and storage volumes. Docker Registry: Public (Docker Hub) or private image repositories. A container lifecycle is tied directly to its primary foreground process (PID 1). When that process exits, the container stops. ...