This page provides details on Container-Optimized OS source code, including how to access Container-Optimized OS image source, source for related container tools, and how to build from source.
Container-Optimized OS image source
Container-Optimized OS from Google is a fork of the Chromium OS open-source project. You can find the majority of the source code for Container-Optimized OS in the COS repositories https://cos.googlesource.com.
Some of the useful resources that can help you determine the source code used to build the image include:
Inside the OS image, the
/opt/google/chrome/resources/about_os_credits.htmlfile contains version and license information for all the packages used to build that image.Kernel source: https://cos.googlesource.com/third_party/kernel/+/cos-5.15.
Kernel config (x86): https://cos.googlesource.com/third_party/kernel/+/refs/heads/cos-5.15/arch/x86/configs/lakitu_defconfig.
Kernel config (Arm): https://cos.googlesource.com/third_party/kernel/+/refs/heads/cos-5.15/arch/arm64/configs/lakitu_defconfig.
The commit SHA1 of the kernel source used to build a particular version is also provided in the release-notes for that version.Additional image artifacts, including archived kernel sources and kernel headers, are also available in a public Google Cloud Storage bucket under
gs://cos-tools/<build-number>/. For example, artifacts forcos-dev-105-17228-0-0are undergs://cos-tools/17228.0.0/.
gcloud storage ls gs://cos-tools/17228.0.0/ gs://cos-tools/17228.0.0/about_os_credits.html gs://cos-tools/17228.0.0/about_os_credits.html.md5 gs://cos-tools/17228.0.0/cos-package-info.json gs://cos-tools/17228.0.0/cos-package-info.json.md5 gs://cos-tools/17228.0.0/cos_full_payload_dev.bin gs://cos-tools/17228.0.0/gpu_R470_version gs://cos-tools/17228.0.0/gpu_R470_version.md5 gs://cos-tools/17228.0.0/gpu_default_version gs://cos-tools/17228.0.0/gpu_default_version.md5 gs://cos-tools/17228.0.0/gpu_latest_version gs://cos-tools/17228.0.0/gpu_latest_version.md5 gs://cos-tools/17228.0.0/kernel-headers.tgz gs://cos-tools/17228.0.0/kernel-headers.tgz.md5 gs://cos-tools/17228.0.0/kernel-src.tar.gz gs://cos-tools/17228.0.0/kernel-src.tar.gz.md5 gs://cos-tools/17228.0.0/kernel_commit gs://cos-tools/17228.0.0/kernel_commit.md5 gs://cos-tools/17228.0.0/kernel_info gs://cos-tools/17228.0.0/kernel_info.md5 gs://cos-tools/17228.0.0/manifest.xml gs://cos-tools/17228.0.0/manifest.xml.md5 gs://cos-tools/17228.0.0/toolchain.tar.xz gs://cos-tools/17228.0.0/toolchain.tar.xz.gcs gs://cos-tools/17228.0.0/toolchain.tar.xz.md5 gs://cos-tools/17228.0.0/toolchain_env gs://cos-tools/17228.0.0/toolchain_env.md5 gs://cos-tools/17228.0.0/vmlinux gs://cos-tools/17228.0.0/vmlinux.md5 gs://cos-tools/17228.0.0/lakitu-arm64/ gs://cos-tools/17228.0.0/lakitu/ - Image artifacts for Arm-based images are available in the public Cloud Storage bucket under
gs://cos-tools/<build-number>/lakitu-arm64/. For example, artifacts forcos-arm64-dev-105-17228-0-0are undergs://cos-tools/17228.0.0/lakitu-arm64/.
gcloud storage ls gs://cos-tools/17228.0.0/lakitu-arm64/ gs://cos-tools/17228.0.0/lakitu-arm64/about_os_credits.html gs://cos-tools/17228.0.0/lakitu-arm64/about_os_credits.html.md5 gs://cos-tools/17228.0.0/lakitu-arm64/cos-package-info.json gs://cos-tools/17228.0.0/lakitu-arm64/cos-package-info.json.md5 gs://cos-tools/17228.0.0/lakitu-arm64/gpu_R470_version gs://cos-tools/17228.0.0/lakitu-arm64/gpu_R470_version.md5 gs://cos-tools/17228.0.0/lakitu-arm64/gpu_default_version gs://cos-tools/17228.0.0/lakitu-arm64/gpu_default_version.md5 gs://cos-tools/17228.0.0/lakitu-arm64/gpu_latest_version gs://cos-tools/17228.0.0/lakitu-arm64/gpu_latest_version.md5 gs://cos-tools/17228.0.0/lakitu-arm64/kernel-headers.tgz gs://cos-tools/17228.0.0/lakitu-arm64/kernel-headers.tgz.md5 gs://cos-tools/17228.0.0/lakitu-arm64/kernel-src.tar.gz gs://cos-tools/17228.0.0/lakitu-arm64/kernel-src.tar.gz.md5 gs://cos-tools/17228.0.0/lakitu-arm64/kernel_commit gs://cos-tools/17228.0.0/lakitu-arm64/kernel_commit.md5 gs://cos-tools/17228.0.0/lakitu-arm64/kernel_info gs://cos-tools/17228.0.0/lakitu-arm64/kernel_info.md5 gs://cos-tools/17228.0.0/lakitu-arm64/manifest.xml gs://cos-tools/17228.0.0/lakitu-arm64/manifest.xml.md5 gs://cos-tools/17228.0.0/lakitu-arm64/toolchain.tar.xz gs://cos-tools/17228.0.0/lakitu-arm64/toolchain.tar.xz.gcs gs://cos-tools/17228.0.0/lakitu-arm64/toolchain.tar.xz.md5 gs://cos-tools/17228.0.0/lakitu-arm64/toolchain_env gs://cos-tools/17228.0.0/lakitu-arm64/toolchain_env.md5 gs://cos-tools/17228.0.0/lakitu-arm64/vmlinux gs://cos-tools/17228.0.0/lakitu-arm64/vmlinux.md5 Those familiar with Chromium OS build system may also find the build recipes under https://cos.googlesource.com/cos/overlays/board-overlays/+/master/project-lakitu/ useful.
Actual source code archives for individual packages can also be found under one of the package mirrors maintained by Chromium OS build system. You can access them by appending the correct tarball name to one of the following URLs:
https://storage.googleapis.com/chromeos-mirror/gentoo/distfiles/https://storage.googleapis.com/chromeos-localmirror/distfiles/For example, to download kubernetes version 1.19.2, use
https://storage.googleapis.com/chromeos-localmirror/distfiles/kubernetes-server-linux-amd64-1.19.2.tar.gz.
The Chromium OS Build FAQ and other Chromium OS Build documentation explains how the build system and package mirrors work.
Container source
Container-Optimized OS from Google ships with some tools that download containers at runtime. Those containers are also open sourced. The following table lists the containers, their source location and release location.
| Containers | Release Location |
|---|---|
| Toolbox | Container Registry gcr.io/cos-cloud/toolbox |
| Cos-gpu-installer | Container Registry gcr.io/cos-cloud/cos-gpu-installer |
| Cloud logging agent | Container Registry gcr.io/stackdriver-agents/stackdriver-logging-agent |
| Konlet agent | Container Registry gcr.io/gce-containers/konlet |
Building from source
Follow the instructions on Building from Open Source to build a Container-Optimized OS disk image from the source.
Source code contributions
Container-Optimized OS does not accept direct contributions from the public.