Which component runs on each node and handles networking rules for pods?

Which component runs on each node and handles networking rules for pods?

• A. Kube-proxy
• B. Kubelet
• C. Etcd
• D. Scheduler

Answer: (A)

The concept tested is how service networking is implemented on each node. Kube-proxy runs on every node and is responsible for configuring the local network rules to direct traffic to the pods backing a Service. It watches the API server for Service and Endpoints objects and uses the node’s network stack (iptables or IPVS) to create the necessary rules that map a service IP and port to the actual pod endpoints. This enables a single Service IP to reach any healthy pod behind that service, with load balancing handled as traffic is routed to the reachable pods. As pods are added or removed, Kube-proxy updates the rules so traffic continues to be directed correctly. The other components have different roles: the Kubelet manages the lifecycle and runtime of containers on the node; etcd stores cluster state; the Scheduler places pods onto nodes. So, the component that runs on each node and handles networking rules for pods is kube-proxy.

The concept tested is how service networking is implemented on each node. Kube-proxy runs on every node and is responsible for configuring the local network rules to direct traffic to the pods backing a Service. It watches the API server for Service and Endpoints objects and uses the node’s network stack (iptables or IPVS) to create the necessary rules that map a service IP and port to the actual pod endpoints. This enables a single Service IP to reach any healthy pod behind that service, with load balancing handled as traffic is routed to the reachable pods. As pods are added or removed, Kube-proxy updates the rules so traffic continues to be directed correctly. The other components have different roles: the Kubelet manages the lifecycle and runtime of containers on the node; etcd stores cluster state; the Scheduler places pods onto nodes. So, the component that runs on each node and handles networking rules for pods is kube-proxy.