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Summary of kubernetes features and terminologies

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Introduction Kubernetes had won the container orchestration war. Here is a summary of its features. It's an API, command line and UI. It uses etcd to keep its state. Every thing is done via Yaml or JSON (your choice). General Node : a machine or instance (used to be called "minion") Namespace: a grouping of resources Label: a tag applied to a resource ex. role=frontend Annotations: another form of meta data  Workloads Container  ( spec ) : the building block of deployable service or runnable task using linux containers ex. docker image and params to pass at runtime. Typically created in a Pod see below Pod  ( spec ) : one of more containers scheduled to nodes together and thus can share volumes. Most common pods have a single container but there are use cases for more (ex. nginx and php-fpm) . If you replicate a pod to have 3 replicas it would have 3 nginx and 3 php-fpm. If php-fpm created a file in the volume, nginx can see it. Typically created