74d513fae0
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>. kubeadm: chroot to new --rootfs arg **What this PR does / why we need it**: This change adds a new --rootfs=path option to kubeadm, and (if provided) chroot()s to this path before performing file operations. This makes it possible to run the kubeadm binary from a container, but perform remaining file operations against the host filesystem using something like: ``` docker run -v /:/rootfs --net=host --uts=host --pid=host \ kubeadm:latest init ... ``` (Assuming something like the included `examples/kubeadm/Dockerfile` which sets CMD to `kubeadm --rootfs=/rootfs` - Edit: Dockerfile has been removed from this PR, but you get the idea) Fixes kubernetes/kubeadm#503 **Special notes for your reviewer**: - I'm not sure where is best to put the Dockerfile, or hook it up to the build process. Advice sought. - The kubeadm command line arg handling was less unified than I was expecting to find. I've implemented this arg for `init` and `join`. I can add it to all the others too, if we're happy with the approach. An alternative would be to add the arg in the parent `KubeadmCommand`, possibly with a `PersistantFlag` - then it would automatically exist for all kubeadm subcommands. - It would be slightly preferable if we could order `--rootfs` _before_ the subcommand so we could apply the arg automatically with `ENTRYPOINT ["kubeadm", "--rootfs=/rootfs"]`. This would be the only such flag in `kubeadm` however, so I have not implemented it that way atm. (Another alternative would be an env var) **Release note**: ```release-note Adds a new EXPERIMENTAL `--rootfs` flag to kubeadm, which (if specified) causes kubeadm to chroot before performing any file operations. This is expected to be useful when setting up kubernetes on a different filesystem, such as invoking kubeadm from docker. ```
Kubernetes
Kubernetes is an open source system for managing containerized applications across multiple hosts; providing basic mechanisms for deployment, maintenance, and scaling of applications.
Kubernetes builds upon a decade and a half of experience at Google running production workloads at scale using a system called Borg, combined with best-of-breed ideas and practices from the community.
Kubernetes is hosted by the Cloud Native Computing Foundation (CNCF). If you are a company that wants to help shape the evolution of technologies that are container-packaged, dynamically-scheduled and microservices-oriented, consider joining the CNCF. For details about who's involved and how Kubernetes plays a role, read the CNCF announcement.
To start using Kubernetes
See our documentation on kubernetes.io.
Try our interactive tutorial.
Take a free course on Scalable Microservices with Kubernetes.
To start developing Kubernetes
The community repository hosts all information about building Kubernetes from source, how to contribute code and documentation, who to contact about what, etc.
If you want to build Kubernetes right away there are two options:
You have a working Go environment.
$ go get -d k8s.io/kubernetes
$ cd $GOPATH/src/k8s.io/kubernetes
$ make
You have a working Docker environment.
$ git clone https://github.com/kubernetes/kubernetes
$ cd kubernetes
$ make quick-release
For the full story, head over to the developer's documentation.
Support
If you need support, start with the troubleshooting guide, and work your way through the process that we've outlined.
That said, if you have questions, reach out to us one way or another.