Which Ports Does a Node Listen On?

10248

TCP

Health check port for kubelet

10250

TCP

Service port of kubelet to provide monitoring information about workloads on nodes and access channels for containers

10255

TCP

Read-only port of kubelet to provide monitoring information about workloads on the node

Dynamic port (related to the range of the host machine, for example, the kernel parameter net.ipv4.ip_local_port_range)

TCP

Random port listened by kubelet, which is used to communicate with CRI Shim to obtain the EXEC URL.

10249

TCP

kube-proxy metric port to provide kube-proxy monitoring information

10256

TCP

Health check port for kube-proxy

Dynamic port (32768-65535)

TCP

WebSocket listening port for functions such as docker exec

Dynamic port (32768-65535)

TCP

WebSocket listening port for functions such as containerd exec

28001

TCP

Local listening port of ICAgent to receive syslog logs of the node

28002

TCP

Health check port for ICAgent

20101

TCP

Health check port of yangtse-agent/canal-agent (involved when the container tunnel network model is used)

20104

TCP

Metric port of yangtse-agent/canal-agent to provide component monitoring information (involved when the container tunnel network model is used)

3125

TCP

Health check listening port of everest-csi-driver

3126

TCP

everest-csi-driver pprof port

19900

TCP

Server port for the health check of node-problem-detector

19901

TCP

Port for connecting node-problem-detector to Prometheus to collect monitoring data

4789

UDP

OVS listening port, which is used to transmit VXLAN packets in container networking (involved when the container tunnel network model is used)

4789

UDPv6

OVS listening port, which is used to transmit VXLAN packets in container networking (involved when the container tunnel network model is used)

Dynamic port (30000-32767)

TCP

Listening port of kube-proxy for layer-4 load balancing. Kubernetes allocates a random port to NodePort and Loadbalancer Services. The default port number ranges from 30000 to 32767.

Dynamic port (30000-32767)

UDP

Listening port of kube-proxy for layer-4 load balancing. Kubernetes allocates a random port to NodePort and Loadbalancer Services. The default port number ranges from 30000 to 32767.

123

UDP

Listening port of ntpd used for time synchronization

20202

TCP

Listening port of PodLB for layer-7 load balancing, which forwards container image pull requests.