K8s architecture

Docker uses a container-runtime to containerize applications known as containerd however K8s allows us to use any container runtime which implements K8s container runtime interface - cri-o, containerd etc

Note: more about runtimes https://docs.docker.com/engine/daemon/alternative-runtimes/

In docker, the docker daemon or docker engine is responsible for creating, running and deleting the containers (smallest unit of docker) while in K8s it is kubelet which is responsible to always keep a pod running (smallest unit of k8s)!
In docker, the networking of containers is taken care by the default bridge network - docker0, in k8s kube-proxy takes care of all the networking related stuff like - assigning ip to pods, creating a load-balancer, etc.

etcd - keeps storage backup of the cluster
api-server - exposes k8s commands as api to the users
scheduler - schedules pods
controller manager - manages replica sets ex- maintain 3 pods of a certain deployment everytime!
cloud-controller-manager - open source controller code for ppl to write their own logic to manage k8s in a cloud platform

Links:

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