Flatcar Container Linux
Flatcar Container Linux is a minimal, immutable, container-optimized Linux operating system and the active successor to CoreOS Container Linux. It is designed to run container workloads consistently across cloud providers, virtualization platforms, and bare-metal environments.
Flatcar uses automated provisioning, read-only system images, and atomic updates to reduce drift and simplify operations. If you’re new to Flatcar, start with Getting Started .
Documentation sections
| Section | Description |
|---|---|
| Getting Started | Quickstart material and the learning series. |
| First Boot & Provisioning | First-boot configuration and provisioning tools. |
| OS Configuration | Host, network, storage, and systemd configuration. |
| System Extensions | Extending the base OS with systemd-sysext. |
| Deployments | Cloud, virtualization, and bare-metal deployment guidance. |
| Orchestration & Container Runtimes | Kubernetes, cluster patterns, and container runtime topics. |
| Diagnostics and Fixing Issues | Troubleshooting tools, logs, and rollback guidance. |
| Nebraska Update Manager & Releases | Nebraska, release channels, and update management. |
| Security | Hardening, authentication, encryption, and supply-chain topics. |
| CoreOS Migration | Migration guidance for CoreOS Container Linux users. |
| Developer Guides | SDK and image-building documentation for developers. |
| How to Contribute | Community and contribution information. |
Community
- Discord: Flatcar Discord server
- GitHub: github.com/flatcar
- Contributing: CONTRIBUTING.md
First Boot & Provisioning
Several different tools can be used to automate the provisioning of Flatcar Container Linux images. These guides can help you understand what each of the tools do, as well as provide plenty of examples of how to use them.
OS Configuration
Configure host settings, networking, storage, and systemd on Flatcar Container Linux. Manage machine parameters, create users, inject SSH keys, and more with Butane configs.
System Extensions
Extending the base OS with systemd-sysext images
Deployments
Deploy Flatcar Container Linux to cloud providers, virtualization platforms, and bare metal.
Orchestration & Container Runtimes
Manage clusters, Kubernetes, and container runtimes on Flatcar Container Linux.
Diagnostics and Fixing Issues
Useful tools and techniques to understand what’s going on inside a Flatcar instance when things don’t work as expected.
Security
Security hardening, encryption, and authentication for Flatcar Container Linux.