flatcar · John15321 · Jul 11, 2026
@@ -29,7 +29,7 @@ When configuring the Flatcar Container Linux iPXE boot script there are a few ke
 - **sshkey**: Add the given SSH public key to the `core` user's `authorized_keys` file. Replace the example key below with your own (it is usually in `~/.ssh/id_rsa.pub`)
 - **console**: Enable kernel output and a login prompt on a given tty. The default, `tty0`, generally maps to VGA. Can be used multiple times, e.g. `console=tty0 console=ttyS0`
 - **flatcar.autologin**: Drop directly to a shell on a given console without prompting for a password. Useful for troubleshooting but use with caution. For any console that doesn't normally get a login prompt by default be sure to combine with the `console` option, e.g. `console=tty0 console=ttyS0 flatcar.autologin=tty1 flatcar.autologin=ttyS0`. Without any argument it enables access on all consoles. Note that for the VGA console the login prompts are on virtual terminals (`tty1`, `tty2`, etc), not the VGA console itself (`tty0`).
-- **flatcar.first_boot=1**: Download an Ignition config and use it to provision your booted system. Ignition configs are generated from Container Linux Configs. See the [config transpiler documentation][cl-configs] for more information. If a local filesystem is used for the root partition, pass this parameter only on the first boot.
+- **flatcar.first_boot=1**: Download an Ignition config and use it to provision your booted system. Ignition configs are generated from Butane Configs. See the [Butane documentation][butane-docs] for more information. If a local filesystem is used for the root partition, pass this parameter only on the first boot.
 - **ignition.config.url**: Download the Ignition config from the specified URL. `http`, `https`, `s3`, and `tftp` schemes are supported.
 - **ip**: Configure temporary static networking for initramfs. This parameter does not influence the final network configuration of the node and is mostly useful for first-boot provisioning of systems in DHCP-less environments. See [Ignition documentation][ignition-kargs-ip] for the complete syntax.
 
@@ -165,7 +165,7 @@ Similar to the [OEM partition][oem] in Flatcar Container Linux disk images, iPXE
 
 Now that you have a machine booted it is time to play around. Check out the [Flatcar Container Linux Quickstart][quickstart] guide or dig into [more specific topics][doc-index].
 
-[cl-configs]: ../../fb-provision/cl-config
+[butane-docs]: ../../fb-provision/butane
 [butane-configs]: ../../fb-provision/butane
 [ignition]: ../../fb-provision/ignition
 [ignition-kargs-ip]: ../../fb-provision/ignition/network-configuration#using-static-ip-addresses-with-ignition

@@ -50,7 +50,7 @@ The latest Flatcar Container Linux ISOs can be downloaded from the image storage
 ## Known limitations
 
 1. UEFI boot is not currently supported. Boot the system in BIOS compatibility mode.
-2. There is no straightforward way to provide an [Ignition config][cl-configs].
+2. There is no straightforward way to provide an [Ignition config][ignition-docs].
    As a workaround though, it is possible to leverage the vga console to assign a password to the core user (sudo passwd core).
    Once a password is set, it would be possible to provide a Butane or an Ignition file via SSH/SCP.
 3. A minimum of 2 GB of RAM is required to boot Flatcar Container Linux via ISO.
@@ -63,5 +63,5 @@ The most common use-case for this ISO is to install Flatcar Container Linux to d
 
 The ISO is configured to start a shell on the console without prompting for a password. This is convenient for installation and troubleshooting, but use caution.
 
-[cl-configs]: ../../fb-provision/cl-config
+[ignition-docs]: ../../fb-provision/ignition/
 [installing-to-disk]: installing-to-disk
@@ -183,5 +183,4 @@ Now that you have a machine booted it is time to play around. Check out the [Fla
 [flatcar-iso]: booting-with-iso
 [butane-section]: #butane-configs
 [flatcar-install]: https://raw.githubusercontent.com/flatcar/init/flatcar-master/bin/flatcar-install
-[cl-configs]: ../../fb-provision/cl-config
 [butane]: ../../fb-provision/butane
@@ -444,7 +444,7 @@ output "ip-addresses" {
 }
 ```
 
-Now you can use the module by declaring the variables and a Container Linux Configuration for a machine.
+Now you can use the module by declaring the variables and a Butane Configuration for a machine.
 First create a `terraform.tfvars` file with your settings:
 
 ```
@@ -453,7 +453,7 @@ machines               = ["mynode"]
 ssh_keys               = ["ssh-rsa AA... me@mail.net"]
 ```
 
-The machine name listed in the `machines` variable is used to retrieve the corresponding [Container Linux Config](../../fb-provision/cl-config/).
+The machine name listed in the `machines` variable is used to retrieve the corresponding [Butane Config](../../fb-provision/butane/).
 For each machine in the list, you should have a `machine-NAME.yaml.tmpl` file with a corresponding name.
 
 For example, create the configuration for `mynode` in the file `machine-mynode.yaml.tmpl` (The SSH key used there is not really necessary since we already set it as VM attribute):
@@ -474,7 +474,7 @@ storage:
         inline: |
           #!/bin/bash
           set -euo pipefail
-           # This script demonstrates how templating and variable substitution works when using Terraform templates for Container Linux Configs.
+           # This script demonstrates how templating and variable substitution works when using Terraform templates for Butane Configs.
           hostname="$(hostname)"
           echo My name is ${name} and the hostname is $${hostname}
 ```

@@ -609,7 +609,7 @@ output "ip-addresses" {
 }
 ```
 
-Now you can use the module by declaring the variables and a Container Linux Configuration for a machine.
+Now you can use the module by declaring the variables and a Butane Configuration for a machine.
 First create a `terraform.tfvars` file with your settings:
 
 ```
@@ -626,7 +626,7 @@ You can resolve the latest Flatcar Stable version with this shell command:
 curl -sSfL https://stable.release.flatcar-linux.net/amd64-usr/current/version.txt | grep -m 1 FLATCAR_VERSION_ID= | cut -d = -f 2
 ```
 
-The machine name listed in the `machines` variable is used to retrieve the corresponding [Container Linux Config](../../fb-provision/butane/configuration) template from the `cl/` subfolder.
+The machine name listed in the `machines` variable is used to retrieve the corresponding [Butane Config](../../fb-provision/butane/configuration) template from the `cl/` subfolder.
 For each machine in the list, you should have a `machine-NAME.yaml.tmpl` file with a corresponding name.
 
 Create the configuration for `mynode` in the file `cl/machine-mynode.yaml.tmpl`:
@@ -646,7 +646,7 @@ storage:
         inline: |
           #!/bin/bash
           set -euo pipefail
-          # This script demonstrates how templating and variable substitution works when using Terraform templates for Container Linux Configs.
+          # This script demonstrates how templating and variable substitution works when using Terraform templates for Butane Configs.
           hostname="$(hostname)"
           echo My name is ${name} and the hostname is $${hostname}
 ```

@@ -326,7 +326,7 @@ output "ip-addresses" {
 }
 ```
 
-Now you can use the module by declaring the variables and a Container Linux Configuration for a machine.
+Now you can use the module by declaring the variables and a Butane Configuration for a machine.
 First create a `terraform.tfvars` file with your settings:
 
 ```
@@ -364,7 +364,7 @@ storage:
         inline: |
           #!/bin/bash
           set -euo pipefail
-           # This script demonstrates how templating and variable substitution works when using Terraform templates for Container Linux Configs.
+           # This script demonstrates how templating and variable substitution works when using Terraform templates for Butane Configs.
           hostname="$(hostname)"
           echo My name is ${name} and the hostname is $${hostname}
 ```

@@ -127,7 +127,7 @@ You can also [upgrade from an existing CoreOS Container Linux system](../../core
 
 ## Butane Config
 
-Flatcar Container Linux allows you to configure machine parameters, configure networking, launch systemd units on startup, and more via Butane Configs. These configs are then transpiled into Ignition configs and given to booting machines. Head over to the [docs to learn about the supported features][cl-configs].
+Flatcar Container Linux allows you to configure machine parameters, configure networking, launch systemd units on startup, and more via Butane Configs. These configs are then transpiled into Ignition configs and given to booting machines. Head over to the [docs to learn about the supported features][butane-docs].
 
 You can provide a raw Ignition JSON config to Flatcar Container Linux via the Google Cloud console's metadata field `user-data` or via a flag using `gcloud`.
 
@@ -328,4 +328,4 @@ Now that you have a machine booted it is time to play around. Check out the [Fla
 [quickstart]: ../../getting-started/quickstart
 [doc-index]: ../../
 [update-strategies]: ../../updates-releases/releases/update-strategies
-[cl-configs]: ../../fb-provision/butane
+[butane-docs]: ../../fb-provision/butane
@@ -172,7 +172,7 @@ IP configuration specified via `guestinfo.interface.*` and `guestinfo.dns.*` var
 
 ### Templating with Butane Configs and setting up metadata
 
-On many cloud providers Ignition will run the [`coreos-metadata.service`](../../fb-provision/ignition/dynamic-data) (which runs `afterburn`) to set up [node metadata](../../fb-provision/cl-config/dynamic-data). This is not the case with VMware because the network setup is defined by you and nothing generic that `afterburn` would know about.
+On many cloud providers Ignition will run the [`coreos-metadata.service`](../../fb-provision/ignition/dynamic-data) (which runs `afterburn`) to set up [node metadata](../../fb-provision/ignition/dynamic-data). This is not the case with VMware because the network setup is defined by you and nothing generic that `afterburn` would know about.
 
 Here's a Butane configuration example to setup an `etcd` instance with a custom `coreos-metadata.service`:
 
@@ -326,7 +326,7 @@ With `should_exist` instead of `should_not_exist` the argument would be added if
 
 Read more about setting kernel command line parameters this way [here](../../os-config/host-config/other-settings#adding-custom-kernel-boot-options).
 
-In case you want to disable the autologin on the console with Ignition v2 where no `kernelArguments` directive exists, you can use the following directive in your Container Linux Config YAML.
+In case you want to disable the autologin on the console with Ignition v2 where no `kernelArguments` directive exists, you can use the following directive in your Butane Config YAML.
 To take effect it requires an additional reboot.
 
 ```yaml
@@ -347,7 +347,7 @@ storage:
           set linux_append=""
 ```
 
-To take effect directly on first boot, the alternative is to create a `getty@.service` drop-in, here a CLC snippet:
+To take effect directly on first boot, the alternative is to create a `getty@.service` drop-in, here a Butane snippet:
 
 ```
 systemd:
@@ -366,7 +366,6 @@ systemd:
 
 Now that you have a machine booted, it's time to explore. Check out the [Flatcar Container Linux Quickstart][quickstart] guide, or dig into [more specific topics][docs].
 
-[cl-configs]: ../../fb-provision/cl-config
 [update-strategies]: ../../updates-releases/releases/update-strategies
 [release-notes]: https://flatcar-linux.org/releases
 [quickstart]: ../../getting-started/quickstart

@@ -18,4 +18,3 @@ Flatcar is configured declaratively at first boot. This section introduces the p
 | [Ignition](./ignition/) | Apply first-boot configuration to a new Flatcar instance. |
 | [Infrastructure](./infrastructure/) | Use infrastructure tooling such as Terraform with Flatcar. |
 | [Image Customization](./customize-image/) | Customize images before first boot when needed. |
-| [cl-config](./cl-config/) | Legacy configuration tooling retained for historical reference. |
@@ -20,7 +20,7 @@ The resulting Ignition config is very much not intended to be human-friendly. It
 [butane]: https://github.com/coreos/butane/
 [ignition]: https://github.com/coreos/ignition
 
-**Note:** Butane is utilized to generate Ignition v3+ configurations. If you are still utilizing a version of Container Linux that requires Ignition v2, you can refer to the [Container Linux Config Transpiler][cl-config] documentation.
+**Note:** Butane is utilized to generate Ignition v3+ configurations. The legacy Container Linux Config Transpiler (used for Ignition v2) has reached end of life and its documentation has been removed; if you're still using it, please migrate to Butane.
 
 ## Why a two-step process?
 
@@ -78,4 +78,3 @@ To turn this Butane Config into a usable Ignition Config, we can then run: `dock
 To learn more about Butane and the configurations that are available, you can refer to the latest [Butane Spec][butane-spec].
 
 [butane-spec]: https://coreos.github.io/butane
-[cl-config]: ../cl-config