How DNS resolution happens?

[SathishSQSH]

Bootstrapped K8S cluster with the recent changes, and the pods running are unable to resolve DNS. I could see DNS nameserver 10.32.0.10. configured in kubelet.

Is there any config needed?like installing coredns or something? or How can i make pod to resolve DNS.

[pfitzmsn]

I just grabbed the latest helm from https://helm.sh/docs/intro/install/ and installed it on the jump server.

Verified helm was good to go on jump server.
$helm version
version.BuildInfo{Version:"v3.14.4", GitCommit:"81c902a123462fd4052bc5e9aa9c513c4c8fc142", GitTreeState:"clean", GoVersion:"go1.21.9"}

Then ran:
$helm --namespace=kube-system install coredns coredns/coredns --set service.clusterIP="10.32.0.10"`

[SathishSQSH]

okay. I could see below config in kubelet config file. If we need coredns, we can simply run the coredns manifests. But how these are interconnected.

clusterDomain: "cluster.local"
clusterDNS:

• "10.32.0.10"

[YievCkim]

Hey there !

I had this problem too, and I don't want to use Helm right now.

I have installed coredns following instruction here and adapting DNS clusterIP

seems to work:

root@jumpbox:~# kubectl exec -ti -n default busybox -- nslookup kubernetes
Server:    10.32.0.10
Address 1: 10.32.0.10 kube-dns.kube-system.svc.cluster.local

Name:      kubernetes
Address 1: 10.32.0.1 kubernetes.default.svc.cluster.local

Hope it helps.