Kubernetes Pod and Container Concepts: Difference between revisions
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* [[Kubernetes_Concepts#Subjects|Kubernetes Concepts]] | * [[Kubernetes_Concepts#Subjects|Kubernetes Concepts]] | ||
=Overview= | =Overview= | ||
A [[#Pod|pod]] is the fundamental, atomic compute unit created and managed by Kubernetes. A pod groups together one or more [[#Container|containers]]. Pods are deployed on [[Kubernetes_Control_Plane_and_Data_Plane_Concepts#Worker_Node|worker nodes]]. A pod has a well-defined [[#Pod_Lifecycle|lifecycle]] with several [[#Pod_Phases|phases]], and the pod's containers can be in one of a well-defined number of [[#Container_States|states]]. Kubernetes is being notified of what happens with a container by [[#Container_Probes|container probes]]. | A [[#Pod|pod]] is the fundamental, atomic compute unit created and managed by Kubernetes. A pod groups together one or more [[#Container|containers]]. There are several [[#Container_Types|types]] of containers: application containers, init containers and ephemeral containers. Pods are deployed on [[Kubernetes_Control_Plane_and_Data_Plane_Concepts#Worker_Node|worker nodes]]. A pod has a well-defined [[#Pod_Lifecycle|lifecycle]] with several [[#Pod_Phases|phases]], and the pod's containers can be in one of a well-defined number of [[#Container_States|states]]. Kubernetes is being notified of what happens with a container by [[#Container_Probes|container probes]]. | ||
=Pod= | =Pod= | ||
Revision as of 18:25, 24 September 2021
External
- https://kubernetes.io/docs/concepts/workloads/pods/ (fully synced ✓)
Internal
Overview
A pod is the fundamental, atomic compute unit created and managed by Kubernetes. A pod groups together one or more containers. There are several types of containers: application containers, init containers and ephemeral containers. Pods are deployed on worker nodes. A pod has a well-defined lifecycle with several phases, and the pod's containers can be in one of a well-defined number of states. Kubernetes is being notified of what happens with a container by container probes.
Pod
A pod is a group of one or more containers Kubernetes deploys and manages a compute unit, and the specification for how to run the containers. Kubernetes will not manage compute entities with smaller granularity, such as containers or processes.
The containers of a pod are atomically deployed and managed as a group. A useful mental model when thinking of a pod is that of a logical host, where all its containers share a context.
Pod Operation Atomicity
The containers in a pod share network resources and storage. From this perspective, a pod can be thought of as a logical host with all its processes (containers) sharing the network stack and the storage available to the host.
Pod Lifecycle
Pod Phases
Pods and Nodes
Pods and Containers
Container
TODO:
Container Types
Application Container
Init Container
Ephemeral Container
Container States
Container Probes
Summary of a relationship between container probe result and overall pod situation.