- This post assumes some familiarity with Kubernetes components such as pods, nodes, and services.
Every worker node in a K8’s environment will have 3 processes running on the server.
- Container runtime
- Kubelet
- kube-proxy
1) Container runtime
This is the process responsible for running the pod containers. It is a not a K8's specific process, it is the process of the container system you are using, for example Docker.
2) kubelet
This is a K8's process that is responsible for running and stopping pods on a node as well as assigning resources to the pods container. This process interfaces with both the container runtime and the node itself.
3) kube-proxy
In a K8's environment there will usually be replicas of each node for failover and load balancing. The K8's components that are responsible for managing what requests go to which node is called a service and a service uses another K8's worker process called kube-proxy to actually do the intelligent request forwarding.