25.1 Linux Containers and Kernel Sharing
In simple terms, Linux containers can be thought of as a lightweight alternative to virtualization. In a virtualized environment, a virtual machine is created that contains and runs the entire guest operating system. The virtual machine, in turn, runs on top of an environment such as a hypervisor that manages access to the physical resources of the host system.
Containers work by using a concept referred to as kernel sharing which takes advantage of the architectural design of Linux and UNIX-based operating systems.
In order to understand how kernel sharing and containers work it helps to first understand the two main components of Linux or UNIX operating systems. At the core of the operating system is the kernel. The kernel, in simple terms, handles all the interactions between the operating system and the physical hardware. The second key component is the root file system which contains all the libraries, files and utilities necessary...