containerd is an industry-standard container runtime with an emphasis on simplicity, robustness, and portability. It is available as a daemon for Linux and Windows, which can manage the complete container lifecycle of its host system: image transfer and storage, container execution and supervision, low-level storage and network attachments, etc.
containerd is a member of CNCF with 'graduated' status.
containerd is designed to be embedded into a larger system, rather than being used directly by developers or end-users.
We are a large inclusive OSS project that is welcoming help of any kind shape or form:
- Documentation help is needed to make the product easier to consume and extend.
- We need OSS community outreach/organizing help to get the word out; manage and create messaging and educational content; and help with social media, community forums/groups, and google groups.
- We are actively inviting new security advisors to join the team.
- New subprojects are being created, core and non-core that could use additional development help.
- Each of the containerd projects has a list of issues currently being worked on or that need help resolving.
- If the issue has not already been assigned to someone or has not made recent progress, and you are interested, please inquire.
- If you are interested in starting with a smaller/beginner-level issue, look for issues with an
exp/beginnertag, for example containerd/containerd beginner issues.
See our documentation on containerd.io:
To get started contributing to containerd, see CONTRIBUTING.
If you are interested in trying out containerd see our example at Getting Started.
There are nightly builds available for download here.
Binaries are generated from main branch every night for Linux and Windows.
Please be aware: nightly builds might have critical bugs, it's not recommended for use in production and no support provided.
The k8s CI dashboard group for containerd contains test results regarding the health of kubernetes when run against main and a number of containerd release branches.
Runtime requirements for containerd are very minimal. Most interactions with
the Linux and Windows container feature sets are handled via runc and/or
OS-specific libraries (e.g. hcsshim for Microsoft).
The current required version of runc is described in RUNC.md.
There are specific features used by containerd core code and snapshotters that will require a minimum kernel version on Linux. With the understood caveat of distro kernel versioning, a reasonable starting point for Linux is a minimum 4.x kernel version.
The overlay filesystem snapshotter, used by default, uses features that were finalized in the 4.x kernel series. If you choose to use btrfs, there may be more flexibility in kernel version (minimum recommended is 3.18), but will require the btrfs kernel module and btrfs tools to be installed on your Linux distribution.
To use Linux checkpoint and restore features, you will need criu installed on
your system. See more details in Checkpoint and Restore.
Build requirements for developers are listed in BUILDING.
Any registry which is compliant with the OCI Distribution Specification is supported by containerd.
For configuring registries, see registry host configuration documentation
For a detailed overview of containerd's core concepts and the features it supports, please refer to the FEATURES.MD document.
Please see RELEASES.md for details on versioning and stability of containerd components.
Downloadable 64-bit Intel/AMD binaries of all official releases are available on our releases page.
For other architectures and distribution support, you will find that many Linux distributions package their own containerd and provide it across several architectures, such as Canonical's Ubuntu packaging.