A city parking API listens on TCP 8080, but a NetworkPolicy allow r…

Question

A city parking API listens on TCP 8080, but a NetworkPolicy allow rule lists protocol UDP and port 8080 for the same Pods. What happens to legitimate client traffic?

Accepted Answer

Clients using TCP 8080 are denied because the allow rule’s protocol does not match the application traffic. — Think of protocol like the language on a shipping label—same street number, wrong language, and the package never gets delivered. NetworkPolicy port rules match both port and protocol, so a UDP allow does not open TCP. Your parking clients speaking TCP stay blocked until the rule says TCP.

Answer

Kubernetes rewrites UDP to TCP automatically when the containerPort is 8080.

Answer

The policy still allows TCP because port number alone matches regardless of protocol.

Answer

Only kube-proxy health checks are blocked; application clients are unaffected.

A city parking API listens on TCP 8080, but a NetworkPolicy allow rule lists protocol UDP and port 8080 for the same Pods. What happens to legitimate client traffic?

Short Explanation

Full Explanation