Chapter 5. Pods and Namespaces
The most important primitive in the Kubernetes API is the Pod. A Pod lets you run a containerized application. In practice, you’ll often encounter a one-to-one mapping between a Pod and a container; however, the use cases discussed in Chapter 8 benefit from declaring more than one container in a single Pod.
In addition to running a container, a Pod can consume other services like storage, configuration data, and much more. Therefore, think of a Pod as a wrapper for running containers while at the same time being able to mix in cross-cutting and specialized Kubernetes features.
Working with Pods
In this chapter, we will look at working with a Pod running only a single container. We’ll discuss all important kubectl commands for creating, modifying, interacting, and deleting using imperative and declarative approaches.
Creating Pods
The Pod definition needs to state an image for every container. Upon creating the Pod object, imperatively or declaratively, the scheduler will assign the Pod to a node, and the container runtime engine will check if the container image already exists on that node. If the image doesn’t exist yet, the engine will download it from a container image registry. By default the registry is Docker ...
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