Production-Grade Container Orchestration

You can constrain a Pod so that it is restricted to run on particular node(s), or to prefer to run on particular nodes. There are several ways to do this and the recommended approaches all use label selectors to facilitate the selection. Often, you do not need to set any such constraints; the scheduler will automatically do a reasonable placement (for example, spreading your Pods across nodes so as not place Pods on a node with insufficient free resources).

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.

Production-Grade Container Orchestration

This page shows a couple of quick ways to create a Calico cluster on Kubernetes. Before you begin Decide whether you want to deploy a cloud or local cluster. Creating a Calico cluster with Google Kubernetes Engine (GKE) Prerequisite: gcloud. To launch a GKE cluster with Calico, include the --enable-network-policy flag. Syntax gcloud container clusters create [CLUSTER_NAME] --enable-network-policy Example gcloud container clusters create my-calico-cluster --enable-network-policy To verify the deployment, use the following command.

This page shows how to use Romana for NetworkPolicy. Before you begin Complete steps 1, 2, and 3 of the kubeadm getting started guide. Installing Romana with kubeadm Follow the containerized installation guide for kubeadm. Applying network policies To apply network policies use one of the following: Romana network policies. Example of Romana network policy. The NetworkPolicy API. What's next Once you have installed Romana, you can follow the Declare Network Policy to try out Kubernetes NetworkPolicy.

The cloud-controller-manager is a Kubernetes control plane component that embeds cloud-specific control logic. The cloud controller manager lets you link your cluster into your cloud provider's API, and separates out the components that interact with that cloud platform from components that only interact with your cluster. By decoupling the interoperability logic between Kubernetes and the underlying cloud infrastructure, the cloud-controller-manager component enables cloud providers to release features at a different pace compared to the main Kubernetes project.

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.

This guide is for application owners who want to build highly available applications, and thus need to understand what types of disruptions can happen to Pods. It is also for cluster administrators who want to perform automated cluster actions, like upgrading and autoscaling clusters. Voluntary and involuntary disruptions Pods do not disappear until someone (a person or a controller) destroys them, or there is an unavoidable hardware or system software error.

_Topology Aware Routing_ provides a mechanism to help keep network traffic within the zone where it originated. Preferring same-zone traffic between Pods in your cluster can help with reliability, performance (network latency and throughput), or cost.