Operators are software extensions to Kubernetes that make use of custom resources to manage applications and their components. Operators follow Kubernetes principles, notably the control loop. Motivation The operator pattern aims to capture the key aim of a human operator who is managing a service or set of services. Human operators who look after specific applications and services have deep knowledge of how the system ought to behave, how to deploy it, and how to react if there are problems.

Lower-level detail relevant to creating or administering a Kubernetes cluster.

Networking is a central part of Kubernetes, but it can be challenging to understand exactly how it is expected to work. There are 4 distinct networking problems to address: Highly-coupled container-to-container communications: this is solved by Pods and localhost communications. Pod-to-Pod communications: this is the primary focus of this document. Pod-to-Service communications: this is covered by Services. External-to-Service communications: this is also covered by Services. Kubernetes is all about sharing machines among applications.

The aggregation layer allows Kubernetes to be extended with additional APIs, beyond what is offered by the core Kubernetes APIs. The additional APIs can either be ready-made solutions such as a metrics server, or APIs that you develop yourself. The aggregation layer is different from Custom Resource Definitions, which are a way to make the kube-apiserver recognise new kinds of object. Aggregation layer The aggregation layer runs in-process with the kube-apiserver.

Production-Grade Container Orchestration

Note: This section links to third party projects that provide functionality required by Kubernetes. The Kubernetes project authors aren't responsible for these projects, which are listed alphabetically. To add a project to this list, read the content guide before submitting a change. More information. Many features rely on specific kernel functionalities and have minimum kernel version requirements. However, relying solely on kernel version numbers may not be sufficient for certain operating system distributions, as maintainers for distributions such as RHEL, Ubuntu and SUSE often backport selected features to older kernel releases (retaining the older kernel version).

Synopsis Check whether an action is allowed. VERB is a logical Kubernetes API verb like 'get', 'list', 'watch', 'delete', etc. TYPE is a Kubernetes resource. Shortcuts and groups will be resolved. NONRESOURCEURL is a partial URL that starts with "/". NAME is the name of a particular Kubernetes resource. This command pairs nicely with impersonation. See --as global flag. kubectl auth can-i VERB [TYPE | TYPE/NAME | NONRESOURCEURL] Examples # Check to see if I can create pods in any namespace kubectl auth can-i create pods --all-namespaces # Check to see if I can list deployments in my current namespace kubectl auth can-i list deployments.

Caution:kubeadm alpha provides a preview of a set of features made available for gathering feedback from the community. Please try it out and give us feedback! Currently there are no experimental commands under kubeadm alpha. What's next kubeadm init to bootstrap a Kubernetes control-plane node kubeadm join to connect a node to the cluster kubeadm reset to revert any changes made to this host by kubeadm init or kubeadm join

Details of the metric data that Kubernetes components export.

Synopsis Set an individual value in a kubeconfig file. PROPERTY_NAME is a dot delimited name where each token represents either an attribute name or a map key. Map keys may not contain dots. PROPERTY_VALUE is the new value you want to set. Binary fields such as 'certificate-authority-data' expect a base64 encoded string unless the --set-raw-bytes flag is used. Specifying an attribute name that already exists will merge new fields on top of existing values.