cri
Note: The standalone cri-containerd
binary is end-of-life. cri-containerd
is
transitioning from a standalone binary that talks to containerd to a plugin within
containerd. This github branch is for the cri
plugin. See
standalone-cri-containerd branch
for information about the standalone version of cri-containerd
.
Note: You need to drain your node before upgrading from standalone cri-containerd
to containerd with cri
plugin.
cri
is a containerd plugin implementation of Kubernetes container runtime interface (CRI).
With it, you could run Kubernetes using containerd as the container runtime.
Current Status
cri
is a native plugin of containerd 1.1 and above. It is built into containerd and enabled by default.
cri
is in GA:
- It is feature complete.
- It (the GA version) works with Kubernetes 1.10 and above.
- It has passed all CRI validation tests.
- It has passed all node e2e tests.
- It has passed all e2e tests.
See test dashboard
Support Metrics
CRI-Containerd Version | Containerd Version | Kubernetes Version | CRI Version |
---|---|---|---|
v1.0.0-alpha.x | 1.7, 1.8 | v1alpha1 | |
v1.0.0-beta.x | 1.9 | v1alpha1 | |
End-Of-Life | v1.1 | 1.10+ | v1alpha2 |
v1.2 | 1.10+ | v1alpha2 | |
HEAD | 1.10+ | v1alpha2 |
Note: The support table above specifies the Kubernetes Version that was supported at time of release of the containerd - cri integration.
The following is the current support table for containerd CRI integration taking into account that Kubernetes only supports n-3 minor release versions and 1.10 and 1.11 are now end-of-life.
Containerd Version | Kubernetes Version | CRI Version |
---|---|---|
v1.1 | 1.12+ | v1alpha2 |
v1.2 | 1.12+ | v1alpha2 |
HEAD | 1.12+ | v1alpha2 |
Although not recommended, if you still plan to use containerd 1.2+ with Kubernetes
<=1.11, please be sure to set disable_proc_mount=true
.
Production Quality Cluster on GCE
For a production quality cluster on GCE brought up with kube-up.sh
refer here.
Installing with Ansible and Kubeadm
For a multi node cluster installer and bring up steps using ansible and kubeadm refer here.
Custom Installation
For non ansible users, you can download the cri-containerd
release tarball and deploy
kubernetes cluster using kubeadm as described here.
Getting Started for Developers
Binary Dependencies and Specifications
The current release of the cri
plugin has the following dependencies:
See versions of these dependencies cri
is tested with.
As containerd and runc move to their respective general availability releases,
we will do our best to rebase/retest cri
with these releases on a
weekly/monthly basis. Similarly, given that cri
uses the Open
Container Initiative (OCI) image
and runtime specifications, we
will also do our best to update cri
to the latest releases of these
specifications as appropriate.
Install Dependencies
- Install development libraries:
- libseccomp development library. Required by
cri
and runc seccomp support.libseccomp-dev
(Ubuntu, Debian) /libseccomp-devel
(Fedora, CentOS, RHEL). On releases of Ubuntu <=Trusty and Debian <=jessie a backport version oflibseccomp-dev
is required. See travis.yml for an example on trusty. - btrfs development library. Required by containerd btrfs support.
btrfs-tools
(Ubuntu, Debian) /btrfs-progs-devel
(Fedora, CentOS, RHEL)
- Install
socat
(required by portforward). - Install and setup a go 1.10 development environment.
- Make a local clone of this repository.
- Install binary dependencies by running the following command from your cloned
cri/
project directory:
# Note: install.deps installs the above mentioned runc, containerd, and CNI
# binary dependencies. install.deps is only provided for general use and ease of
# testing. To customize `runc` and `containerd` build tags and/or to configure
# `cni`, please follow instructions in their documents.
make install.deps
cri
Build and Install To build and install a version of containerd with the cri
plugin, enter the
following commands from your cri
project directory:
make
sudo make install
NOTE: The version of containerd built and installed from the Makefile
is only for
testing purposes. The version tag carries the suffix "-TEST".
Build Tags
cri
supports optional build tags for compiling support of various features.
To add build tags to the make option the BUILD_TAGS
variable must be set.
make BUILD_TAGS='seccomp apparmor'
Build Tag | Feature | Dependency |
---|---|---|
seccomp | syscall filtering | libseccomp development library |
selinux | selinux process and mount labeling | |
apparmor | apparmor profile support |
cri
Setup
Validate Your A Kubernetes incubator project called cri-tools
includes programs for exercising CRI implementations such as the cri
plugin.
More importantly, cri-tools includes the program critest
which is used for running
CRI Validation Testing.
Run the CRI Validation test to validate your installation of containerd
with cri
built in:
make test-cri
Running a Kubernetes local cluster
If you already have a working development environment for supported Kubernetes
version, you can try cri
in a local cluster:
- Start the version of
containerd
withcri
plugin that you built and installed above as root in a first terminal:
sudo containerd
- From the Kubernetes project directory startup a local cluster using
containerd
:
CONTAINER_RUNTIME=remote CONTAINER_RUNTIME_ENDPOINT='unix:///run/containerd/containerd.sock' ./hack/local-up-cluster.sh
Test
See here for information about test.
Using crictl
See here for information about using crictl
to debug
pods, containers, and images.
Configurations
See here for information about how to configure cri plugins and here for information about how to configure containerd
Documentation
See here for additional documentation.
Contributing
Interested in contributing? Check out the documentation.
Communication
This project was originally established in April of 2017 in the Kubernetes Incubator program. After reaching the Beta stage, In January of 2018, the project was merged into containerd.
For async communication and long running discussions please use issues and pull requests on this github repo. This will be the best place to discuss design and implementation.
For sync communication we have a community slack with a #containerd channel that everyone is welcome to join and chat about development.
Slack: Catch us in the #containerd and #containerd-dev channels on dockercommunity.slack.com. Click here for an invite to docker community slack.
Other Communications
As this project is tightly coupled to CRI and CRI-Tools and they are Kubernetes
projects, some of our project communications take place in the Kubernetes' SIG:
sig-node.
For more information about sig-node
, CRI
, and the CRI-Tools
projects:
- sig-node community site
- Slack:
#sig-node
channel in Kubernetes (kubernetes.slack.com) - Mailing List: https://groups.google.com/forum/#!forum/kubernetes-sig-node
Reporting Security Issues
If you are reporting a security issue, please reach out discreetly at security@containerd.io.
Licenses
The containerd codebase is released under the Apache 2.0 license. The README.md file, and files in the "docs" folder are licensed under the Creative Commons Attribution 4.0 International License under the terms and conditions set forth in the file "LICENSE.docs". You may obtain a duplicate copy of the same license, titled CC-BY-4.0, at http://creativecommons.org/licenses/by/4.0/.
Code of Conduct
This project follows the CNCF Code of Conduct.