Dns not resolving *.svc.cluster.local only *.svc

General Discussions
1

Cluster information:

Kubernetes version: v1.27.4
Cloud being used: bare-metal
Installation method: kubeadm
Host OS: rocky8
CNI and version: v1.1.1
CRI and version: containerd.io-1.6.22

hello everyone
i updated my k8s from version 1.24 to 1.27
i notice that i can’t resolve the names with .cluster.local anymore.
works:

kubectl exec -it dnsutils -- nslookup tata.titi-dev.svc
Server: xx.xx.xx.xx.
Address: xx.xx.xx.xx#53 Name: tata.titi-dev.svc.cluster.local
Address: xx.xx.xx.xx

Doesn’t work

kubectl exec -it dnsutils -- nslookup tata.titi-dev.svc.cluster.local
Server: xx.xx.xx.xx
Address: xx.xx.xx.xx#53
*** Can't find tata.titi-dev.svc.cluster.local: No answer
is this normal behavior for 1.27 ?
this behavior has appeared since the upgrade.

kubectl -n kube-system get cm coredns -o yaml
apiVersion: v1
data:
  Corefile: |
    .:53 {
        errors
        health {
            lameduck 5s
        }
        ready
        kubernetes cluster.local in-addr.arpa ip6.arpa {
          pods insecure
          fallthrough in-addr.arpa ip6.arpa
        }
        prometheus :9153
        forward . /etc/resolv.conf {
          prefer_udp
        }
        cache 30
        loop
        reload
        loadbalance
    }
  Corefile-backup: |
    .:53 {
        errors
        health {
            lameduck 5s
        }
        ready
        kubernetes cluster.local in-addr.arpa ip6.arpa {
          pods insecure
          fallthrough in-addr.arpa ip6.arpa
        }
        prometheus :9153
        forward . /etc/resolv.conf {
          prefer_udp
        }
        cache 30
        loop
        reload
        loadbalance
    }
kind: ConfigMap
metadata:
  creationTimestamp: "2021-09-28T19:11:11Z"
  name: coredns
  namespace: kube-system
  resourceVersion: "160908307"
  uid: 1cf287e8-6ac7-4b30-98a0-e36462343ad4

whan i add . at the end it works , where is the problem

[root@xxxxxxx ~]# kubectl exec -it dnsutils -- nslookup google.com.
Server:         169.254.20.10
Address:        169.254.20.10#53

Non-authoritative answer:
Name:   google.com
Address: 216.58.214.78

[root@xxxxxxx ~]# kubectl exec -it dnsutils -- nslookup google.com
Server:         169.254.20.10
Address:        169.254.20.10#53

*** Can't find google.com: No answer

[root@xxxxxxxxx ~]# kubectl exec -it dnsutils -- nslookup hub.j-hub-dev2.svc.cluster.local
Server:         169.254.20.10
Address:        169.254.20.10#53

*** Can't find hub.j-hub-dev2.svc.cluster.local: No answer

[root@xxxxxxxxxx ~]# kubectl exec -it dnsutils -- nslookup hub.j-hub-dev2.svc.cluster.local.
Server:         169.254.20.10
Address:        169.254.20.10#53

Name:   hub.j-hub-dev2.svc.cluster.local
Address: 192.168.40.80

Thank you for your answers