Garden Linux is a Debian GNU/Linux derivate that aims to provide small, auditable Linux images for most cloud providers (e.g. AWS, Azure, GCP etc.) and bare-metal machines. Garden Linux is the best Linux for Gardener nodes. Garden Linux provides great possibilities for customizing that is made by a highly customizable feature set to fit your needs.
- Easy to use build system
- Repeatable and auditable builds
- Small footprint
- Purely systemd based (network, fstab etc.)
- Initramfs is dracut generated
- Running latest LTS Kernel
- MIT license
- Security
- Fully immutable image(s) (optional)
- OpenSSL 3.0 (default)
- CIS Framework (optional)
- Testing
- Unit tests (Created image testing)
- Integration tests (Image integration tests in all supported platforms)
- License violations (Testing for any license violations)
- Outdated software versions (Testing for outdated software)
- Supporting major platforms out-of-the-box
- Major cloud providers AWS, Azure, Google, Alicloud
- Major virtualizer VMware, OpenStack, KVM
- Bare-metal systems
The entire build runs in a privileged Podman/Docker container that orchestrates all further actions. If not explicitly skipped, unit tests will be performed. Extended capabilities are at least needed for loop back support. Currently AMD64 and ARM64 architectures are supported.
By default, Garden Linux uses Podman as container runtime (Docker is optionally supported) for building Garden Linux images (Garden Linux artifacts however will have Docker in them to maintain compatibility with older Kubernetes versions). If - for whatever reason - you want or need to use Docker instead, you can set the environment variable GARDENLINUX_BUILD_CRE=docker before invoking the build.
System:
- RAM: 2+ GiB (use '--lessram' to lower memory usage)
- Disk: 10+ GiB (20+ GiB for running
integration tests) - Internet connection
Packages:
Debian/Ubuntu:
apt install bash sudo podman crun make coreutils gnupg git qemu-system-x86 qemu-system-aarch64
CentOS/RedHat (>=8):
CFSSL requires GLIBC 2.28. Therefore, we recommand to build on systems running CentOS/RedHat 8 or later.
# Install needed packages
yum install bash sudo podman crun make gnupg git qemu-kvm qemu-img coreutils
macOS (>=12):
Build support on macOS (>=12) supports Intel (AMD64) and Apple Silicon (ARM64/AARCH64) architectures. Building on macOS requires the GNU versions of multiple tools that can be installed in different ways like Brew, MacPorts or self compiled. Self compiled GNU packages must be located in /opt/local/bin/. However, the following build instructions only cover the recommended Brew way.
Furthermore, building on macOS requires to fulfill further build requirements:
- Command Line Tools (CLT) for Xcode
- Homebrew (Optionally: MacPorts https://macports.org)
- Docker
# Install needed packages
brew install coreutils bash gnu-getopt gnu-sed gawk podman
# Change to bash (Default: ZSH)
$> bash
# Export Docker as Container Runtime Environment for Garden Linux
$> export GARDENLINUX_BUILD_CRE=docker
Adjust Repository:
Note: This is not needed on macOS.
Add docker.io to unqualified-search-registries in your registries.conf. On freshly installed Podman systems this can be done by executing:
echo 'unqualified-search-registries = ["docker.io"]' | sudo tee -a /etc/containers/registries.conf
If Podman was already present please add the repository yourself to unqualified-search-registries in /etc/containers/registries.conf.
Kernel Modules:
- ext4
- loop
- squashfs
- vfat
- vsock (image builds and extended virtualized tests)
| Option | Description |
|---|---|
| --features | Comma separated list of features activated (see features/) (default:base) |
| --disable-features | Comma separated list of features to deactivate (see features/) |
| --lessram | Build will be no longer in memory (default: off) |
| --debug | Activates basically `set -x` everywhere (default: off) |
| --manual | Built will stop in build environment and activate manual mode (default:off) |
| --arch | Builds for a specific architecture (default: architecture the build runs on) |
| --suite | Specifies the debian suite to build for e.g. bullseye, potatoe (default: testing) |
| --skip-tests | Deactivating tests (default: off) |
| --tests | Test suite to use, available tests are unittests, kvm, chroot (default: unittests) |
| --skip-build | Do not create the build container |
To build all supported images you may just run the following command:
make all
However, to save time you may also build just a platform specific image by running one of the following commands. Related dev images can be created by appending the '-dev' suffix (e.g. "make aws-dev").
make aws
make gcp
make azure
make ali
make vmware
make openstack
make kvm
make metal
Artifacts are located in the .build/ folder of the project's build directory.
The Garden Linux pipeline supports cross-building on Linux based systems and requires binfmt support. binfmt support can easily be installed via packages from the used distribution. Afterwards, the build option --arch must be defined to the target arch (e.g. --arch arm64). Currently, amd64 and arm64 are supported and must be explicitly defined for cross-building.
Package Installation
Debian:
apt-get install binfmt-support
CentOS:
yum install qemu-user-binfmt
macOS:
Not supported.
Building Garden Linux is based on a feature system.
| Feature Type | Includes |
|---|---|
| Platforms | ali, aws, azure, gcp, kvm, metal, ... |
| Features | container host, vitual host, ... |
| Modifiers | _slim, _readonly, _pxe, _iso, ... |
| Element | cis, fedramp, gardener |
if you want to build manually choose:
build.sh --features <Platform>,[<feature1>],[<featureX>],[_modifier1],[_modifierX] destination [version]
Additionally, please find some build.sh example calls in the Makefile.
Example:
build.sh --features server,cloud,cis,vmware .build/
This builds a server image, cloud-like, with CISfeature for the VMware platform. The build result can be found in .build/. Also look into our Version scheme since adding a date or a Version targets the whole build for a specific date.
Deploying on common cloud platforms requires additional packages. The following overview gives a short quick start to run cloud platform deployments. Currently, all modules are based on Python. Therefore, please make sure to have Python installed.
| Platform | Module |
|---|---|
| Alicloud | Aliyun CLI |
| AWS: | AWS CLI |
| Azure | Azure CLI |
| GCP: | Cloud SDK, gsutil |
| OpenStack | OpenStackCLI |
Garden Linux frequently publishes snapshot releases. These are available as machine images in most major cloud providers as well as file-system images for manual import. See the releases page for more info.
Garden Linux provides a great documentation for build options, customizing, configuration, tests and pipeline integrations. The documentation can be found within the project's docs/ path or by clicking here. Next to this, you may find a corresponding README.md in each directory explaning some more details. Below, you may find some important documentations for continous integration and integration tests.
Garden Linux can build in an automated way for continous integration. See ci/README.md for details.
While it may be confusing for beginners we highlight this chapter for integration tests here. Garden Linux supports integration testing on all major cloud platforms (Alicloud, AWS, Azur, GCP). To allow testing even without access to any cloud platform we created an universal kvm platform that may run locally and is accessed in the same way via a ssh client object as any other cloud platform. Therefore, you do not need to adjust tests to perform local integration tests. Just to mention here that there is another platform called chroot. This platform is used to perform unit tests and will run as a local integration test. More details can be found within the documentation in tests/README.md.
Feel free to add further documentation, to adjust already existing one or to contribute with code. Please take care about our style guide and naming conventions. More information are available in in CONTRIBUTING.md and our docs/.
Garden Linux has a large grown community. If you need further asstiance, have any issues or just want to get in touch with other Garden Linux users feel free to join our public chat room on Gitter.