Flatcar Container Linux

    Flatcar Container Linux is a container optimized OS that ships a minimal OS image, which includes only the tools needed to run containers. The OS is shipped through an immutable filesystem and includes automatic atomic updates.

    Getting Started

    If you’re new to Flatcar and if you’re looking for a brief introduction on getting Flatcar up and running, please have a look at our quickstart guide .

    Installing Flatcar

    Flatcar Container Linux runs on most cloud providers, virtualization platforms and bare metal servers.

    Cloud Providers

    Virtualization options

    It’s easy to run a local Flatcar VM on your laptop for testing and debugging purposes. You can use any of the following options.

    Bare Metal

    You can install Flatcar on bare metal machines in different ways: using ISO images, booting from PXE or iPXE, and even by running an installation script on an existing Linux system.

    If you want to provide metadata to your baremetal machines, we recommend using Matchbox .

    Upgrading from CoreOS Container Linux

    Flatcar Container Linux is a drop-in replacement of CoreOS Container Linux. If you are a CoreOS Container Linux user looking for a replacement, checkout our guides to migrate from CoreOS Container Linux , or you can update from CoreOS Container Linux directly.

    Provisioning Tools

    Ignition is the recommended way to provision Flatcar Container Linux at first boot. Ignition uses a JSON configuration file, and it is recommended to generate it from the Container Linux Config YAML format, which has additional features. The Container Linux Config Transpiler converts a Container Linux Config to an Ignition config.

    Setting Flatcar Up and Common Operations

    Follow these guides to connect your machines together as a cluster, configure machine parameters, create users, inject multiple SSH keys, and more.

    Customizing Flatcar

    Managing Releases and Updates

    Creating Clusters

    Managing Storage

    Additional security options

    Debugging Flatcar

    Container Runtimes

    Flatcar Container Linux supports all of the popular methods for running containers, and you can choose to interact with the containers at a low-level, or use a higher level orchestration framework. Listed below are some guides to help you choose and make use of the different runtimes.

    Developer guides and Reference

    APIs and troubleshooting guides for working with Flatcar Container Linux.

    Tutorial

    Flatcar tutorial to deep dive into some Flatcar fundamental concepts.


    Getting Started with Flatcar Container Linux

    Flatcar tutorial

    Provisioning Tools

    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.

    Setup and Operations

    Follow these guides to connect your machines together as a cluster. Configure machine parameters, create users, inject multiple SSH keys, and more with Butane configs.

    Container Runtimes

    Flatcar Container Linux supports all of the popular methods for running containers, and you can choose to interact with the containers at a low-level, or use a higher level orchestration framework. These guides can help you choose and use the different container runtimes supported.

    Migration from CoreOS Container Linux

    Reference

    Processes, concepts, APIs and troubleshooting guides for working with Flatcar Container Linux.

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