Beyond the VM Illusion: Understanding Containers' Three Kernel Mechanisms

Containers represent a fundamental shift in deployment technology, leveraging three Linux kernel mechanisms—namespaces, cgroups, and layered filesystems—to provide VM-like isolation at a fraction of the cost and complexity. Understanding this distinction is crucial: while containers enable unprecedented density, speed, and portability, their shared kernel architecture introduces security vulnerabilities and Linux-specific limitations that make VMs remain essential in certain scenarios.