Note: To file an issue for any Flatcar repository, please use the central Flatcar issue tracker.

System Initialization for Flatcar Container Linux

Flatcar uses systemd for init and process management. This repo is divided into three collections of files:

• configs: Customized daemon configuration files, usually installed into /etc but really the sky is the limit there.
• scripts: Helper scripts for init and service startup. These are generally to be used as systemd oneshot services and installed into /usr/lib/flatcar.
• systemd: Unit files for mount points, our helper scripts, or other services that don't install their own unit files.

The coreos-base/coreos-init ebuild handles the install process.

Important Steps

A few notes on things that must happen which are unique to Flatcar.

• resize btrfs: Support easy VM growth by checking if there is unused space at the end of the disk and expanding the filesystem to use it.
• mount /: This directory can be completely empty.
• initialize /: The / partition can be completely formatted by the user. Run systemd-tmpfiles to set everything up into a known state.
• mount /usr: The entire distro lives in this directory.
• mount /oem: If an OEM is available on disk make sure it gets mounted here.
• generate ssh keys: The stock sshd units do not handle this so we need to.

---

Community & Project Documentation

• Contributing Guidelines — How to contribute, find issues, and submit pull requests
• Code of Conduct — Standards for respectful and inclusive community participation
• Security Policy — How to report vulnerabilities and security-related information
• Maintainers — Current project maintainers and their responsibilities
• Governance — Project governance model, decision-making process, and roles