Alpine Linux is a small, security-oriented, lightweight Linux distribution based on the musl libc library and BusyBox utilities platform instead of GNU. It operates on bare-metal hardware, in a VM or even on a Raspberry Pi. The distribution is noncommercial and evolved for embedded and server-based workloads, although desktop OS use is possible.
The hardened Alpine Linux kernel with an unofficial port of grsecurity patch, with LibreSSL Secure Sockets Layer and OpenRC initialization (init) system, contribute to a secure distribution. An Alpine Linux user will find most things disabled or not installed by default, another security strategy for the OS. Other security features prevent stack buffer overflow and memory corruption for every package.
The Alpine Linux distribution occupies at minimum 130 MB -- about 300 MB for the standard size -- of storage and can run from diskless or disk installs. It uses the apk package manager, which adds, deletes and repairs packages. While Alpine Linux is general purpose, the base design is sparse without GNU utilities, to maintain a small footprint. The user is expected to choose from thousands of packages and install those that meet the needs of a specific workload. A user can also build a custom and unique package.
Alpine Linux is a popular OS choice to run containers, although it is not geared specifically for that task. The container environment has a small footprint; however, Alpine Linux requires considerable installation effort to get Docker running correctly. The Alpine Linux network connection for container operations involves manually creating the /etc/network/interfaces file, for example. The learning curve for Alpine Linux is steeper than other container-centric OSes, such as RancherOS and Boot2Docker, which are designed to be plug-and-play container environments. Because it uses alternative Linux components, Alpine Linux may be less familiar for a container admin than Red Hat Enterprise Linux Atomic Host or Windows Server 2016.
To use Alpine Linux, the administrator must be familiar with the vi text editor, common in Linux distributions. As such, it may be difficult for Windows and Mac users to pick up.
Development and versions
Alpine Linux's current development tree is demarcated as edge and the production-ready version as stable. Releases are generally supported for two years; four versions are supported currently, in addition to the rolling development edition of edge.