I am running 2 pods busybox and nginx in the namespace called webcn
have exposed the nginx pod as a service
i am trying to understand working of name resolution in kubernetes within a namespace from busybox pod
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl get pods busybox nginx -n webcn
NAME READY STATUS RESTARTS AGE
busybox 1/1 Running 33 (8h ago) 56d
nginx 1/1 Running 33 (8h ago) 56d
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl get svc nginx -n webcn
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
nginx ClusterIP 10.108.64.229 <none> 80/TCP 54d
verifying name resolution from busybox pod running in the same namespace
#we can see the short name for service (nginx) and fqdn (nginx.webcn.svc.cluster.local) are resolving as expected also resolves without issues
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl exec -it busybox -n webcn -- nslookup nginx
Server: 10.96.0.10
Address: 10.96.0.10:53
** server can't find nginx.svc.cluster.local: NXDOMAIN
** server can't find nginx.svc.cluster.local: NXDOMAIN
** server can't find nginx.cluster.local: NXDOMAIN
Name: nginx.webcn.svc.cluster.local
Address: 10.108.64.229
** server can't find nginx.dns.podman: NXDOMAIN
** server can't find nginx.dns.podman: NXDOMAIN
** server can't find nginx.cluster.local: NXDOMAIN
command terminated with exit code 1
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl exec -it busybox -n webcn -- nslookup nginx.webcn.svc.cluster.local
Server: 10.96.0.10
Address: 10.96.0.10:53
Name: nginx.webcn.svc.cluster.local
Address: 10.108.64.229
**but queries with . and ..svc are failing in my setup **
which should also resolve correctly as per my understanding
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl exec -it busybox -n webcn -- nslookup nginx.webcn
Server: 10.96.0.10
Address: 10.96.0.10:53
** server can't find nginx.webcn: NXDOMAIN
** server can't find nginx.webcn: NXDOMAIN
command terminated with exit code 1
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl exec -it busybox -n webcn -- nslookup nginx.webcn.svc
Server: 10.96.0.10
Address: 10.96.0.10:53
** server can't find nginx.webcn.svc: NXDOMAIN
** server can't find nginx.webcn.svc: NXDOMAIN
command terminated with exit code 1
the DNS configuration on the busybox pod is configured with correct DNS service and proper search domains
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl exec -it busybox -n webcn -- cat /etc/resolv.conf
nameserver 10.96.0.10
search webcn.svc.cluster.local svc.cluster.local cluster.local dns.podman
options ndots:5
vajra@ubuntu-minikube:~/kubernetes-learn$: kubectl get svc kube-dns -n kube-system
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kube-dns ClusterIP 10.96.0.10 <none> 53/UDP,53/TCP,9153/TCP 56d
Setup information
3 node minikube cluster
CNI : calico
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl version
Client Version: v1.32.1
Kustomize Version: v5.5.0
Server Version: v1.31.0
vajra@ubuntu-minikube:~/kubernetes-learn$ : minikube version
minikube version: v1.34.0
commit: 210b148df93a80eb872ecbeb7e35281b3c582c61
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl get nodes
NAME STATUS ROLES AGE VERSION
minikube Ready control-plane 56d v1.31.0
minikube-m02 Ready <none> 56d v1.31.0
minikube-m03 Ready <none> 56d v1.31.0
CoreDNS configuration
vajra@ubuntu-minikube:~/kubernetes-learn$ : kubectl get cm coredns -n kube-system -o yaml
apiVersion: v1
data:
Corefile: |
.:53 {
log
errors
health {
lameduck 5s
}
ready
kubernetes cluster.local in-addr.arpa ip6.arpa {
pods insecure
fallthrough in-addr.arpa ip6.arpa
ttl 30
}
prometheus :9153
hosts {
10.255.255.254 host.minikube.internal
fallthrough
}
forward . /etc/resolv.conf {
max_concurrent 1000
}
cache 30
loop
reload
loadbalance
}
kind: ConfigMap
metadata:
creationTimestamp: "2025-05-27T06:44:08Z"
name: coredns
namespace: kube-system
resourceVersion: "374"
uid: 23598043-6063-439a-be6d-29b4ef14cac0
what am i missing ??