Showing posts from July, 2017

Summary of kubernetes features and terminologies

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). GeneralNode: a machine or instance (used to be called "minion")Namespace: a grouping of resourcesLabel: a tag applied to a resource ex. role=frontendAnnotations: another form of meta data  WorkloadsContainer (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 belowPod (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 on its own or by controllers like a Re…