8df33bc1a7
separated from the apiserver running locally on the master node so that it can be optionally enabled or disabled as needed. Also, fix the healthchecking configuration for the master components, which was previously only working by coincidence: If a kubelet doesn't register with a master, it never bothers to figure out what its local address is. In which case it ends up constructing a URL like http://:8080/healthz for the http probe. This happens to work on the master because all of the pods are using host networking and explicitly binding to 127.0.0.1. Once the kubelet is registered with the master and it determines the local node address, it tries to healthcheck on an address where the pod isn't listening and the kubelet periodically restarts each master component when the liveness probe fails.
Kubernetes
Are you ...
- Interested in learning more about using Kubernetes? Please see our user-facing documentation on kubernetes.io
- Interested in hacking on the core Kubernetes code base? Keep reading!
Kubernetes is an open source system for managing containerized applications across multiple hosts, providing basic mechanisms for deployment, maintenance, and scaling of applications.
Kubernetes is:
- lean: lightweight, simple, accessible
- portable: public, private, hybrid, multi cloud
- extensible: modular, pluggable, hookable, composable
- self-healing: auto-placement, auto-restart, auto-replication
Kubernetes builds upon a decade and a half of experience at Google running production workloads at scale, combined with best-of-breed ideas and practices from the community.
Kubernetes can run anywhere!
However, initial development was done on GCE and so our instructions and scripts are built around that. If you make it work on other infrastructure please let us know and contribute instructions/code.
Kubernetes is ready for Production!
With the 1.0.1 release Kubernetes is ready to serve your production workloads.
Concepts
Kubernetes works with the following concepts:
- Cluster
- A cluster is a set of physical or virtual machines and other infrastructure resources used by Kubernetes to run your applications. Kubernetes can run anywhere! See the Getting Started Guides for instructions for a variety of services.
- Node
- A node is a physical or virtual machine running Kubernetes, onto which pods can be scheduled.
- Pod
- Pods are a colocated group of application containers with shared volumes. They're the smallest deployable units that can be created, scheduled, and managed with Kubernetes. Pods can be created individually, but it's recommended that you use a replication controller even if creating a single pod.
- Replication controller
- Replication controllers manage the lifecycle of pods. They ensure that a specified number of pods are running at any given time, by creating or killing pods as required.
- Service
- Services provide a single, stable name and address for a set of pods. They act as basic load balancers.
- Label
- Labels are used to organize and select groups of objects based on key:value pairs.
Documentation
Kubernetes documentation is organized into several categories.
- Getting started guides
- for people who want to create a Kubernetes cluster
- for people who want to port Kubernetes to a new environment
- User documentation
- for people who want to run programs on an existing Kubernetes cluster
- in the Kubernetes User Guide: Managing Applications
- the Kubectl Command Line Interface is a detailed reference on
the
kubectlCLI - User FAQ
- Cluster administrator documentation
- for people who want to create a Kubernetes cluster and administer it
- in the Kubernetes Cluster Admin Guide
- Developer and API documentation
- for people who want to write programs that access the Kubernetes API, write plugins or extensions, or modify the core Kubernete code
- in the Kubernetes Developer Guide
- see also notes on the API
- see also the API object documentation, a detailed description of all fields found in the core API objects
- Walkthroughs and examples
- hands-on introduction and example config files
- in the user guide
- in the docs/examples directory
- Contributions from the Kubernetes community
- in the docs/contrib directory
- Design documentation and design proposals
- for people who want to understand the design of Kubernetes, and feature proposals
- design docs in the Kubernetes Design Overview and the docs/design directory
- proposals in the docs/proposals directory
- Wiki/FAQ
- in the wiki
- troubleshooting information in the troubleshooting guide
Community, discussion and support
If you have questions or want to start contributing please reach out. We don't bite!
Please see the troubleshooting guide, or how to get more help.
If you are a company and are looking for a more formal engagement with Google around Kubernetes and containers at Google as a whole, please fill out this form and we'll be in touch.