Lightweight containers have made running a single process without normal init systems like systemd or sysvinit practical. However, omitting an init system often leads to incorrect handling of processes and signals, and can result in problems such as containers that can’t be gracefully stopped, or leaking containers that should have been destroyed. dumb-init is simple to use and solves many of these problems: you can just add it to the front of any container’s command, and it will take on the role of PID 1 for itself. It immediately spawns your process as PID ~2, and then proxies on any signals it receives. This helps to avoid special kernel behavior applied to PID 1, while also handling regular responsibilities of the init system (like reaping orphaned zombie processes). dumb-init is a simple process supervisor and init system designed to run as PID 1 inside minimal container environments (such as Docker). It is deployed as a small, statically-linked binary written in C.
Features
- dumb-init enables you to simply prefix your command with dumb-init
- It acts as PID 1 and immediately spawns your command as a child process
- Takes care to properly handle and forward signals as they are received
- The Linux kernel applies special signal handling to processes which run as PID 1.
- dumb-init runs as PID 1, acting like a simple init system
- It launches a single process and then proxies all received signals to a session rooted at that child process
Project Samples
