One of my kubernetes Node, I see my kubelet listening on port 38641. How to map this port number to actual POD its pointing too.
# netstat -alpn |grep 38641
tcp 0 0 127.0.0.1:38641 0.0.0.0:* LISTEN 9832/kubelet
tcp 0 0 127.0.0.1:45230 127.0.0.1:38641 CLOSE_WAIT 9832/kubelet
tcp 0 0 127.0.0.1:39922 127.0.0.1:38641 CLOSE_WAIT 9832/kubelet
tcp 0 0 127.0.0.1:39238 127.0.0.1:38641 ESTABLISHED 9832/kubeletI assume you have exposed a service in kubernetes using the NodePort type which would account for the high port number. If this is the case, you can simply get a list of all services running in the cluster and search then for the port you want. ie.
kubectl get svc --all-namespaces | grep 38641
Once you have the service which exposes this port, you can then inspect the service and see which pods are being selected by the service
PORT=38641
SERVICE_OUTPUT=$(kubectl get svc --all-namespaces | grep $PORT)
NAMESPACE=$(echo $SERVICE_OUTPUT | awk '{ print $1 }')
SERVICE=$(echo $SERVICE_OUTPUT | awk '{ print $2 }')
kubectl describe -n $NAMESPACE svc $SERVICENow let's get the selector:
SELECTOR=$(kubectl describe -n $NAMESPACE svc $SERVICE | grep Selector | awk '{ print $2}')Ok, now that we know what pods are being selected we can find these pods easily:
kubectl get po --selector $SELECTOR -n $NAMESPACE
We can capture the pod names for further inspection, such as for determining the replicaset they are from:
PODS=$(kubectl get po --selector $SELECTOR -n $NAMESPACE --no-headers=true | awk '{ print $1}')
echo $PODS
If you need to you can trace the pod origin:
POD=full-pod-name
RS=$(kubectl -n $NAMESPACE describe po $POD | grep -hoe ReplicaSet.*);
echo rs: $RS;
DEPLOYMENT=$(kubectl -n $NAMESPACE describe $RS | grep -hoe Deployment.*);
echo deployment: $DEPLOYMENT;