SERVICE discovery

General Discussions
1

Cluster DNS:

|Object |Host name |Name space |type|Root |IP address |
|Service|Web-service (Service name)|my-namespace|svc |cluster.local|10.107.37.188|
|Pod |10-24-5-2 ( Pod ip separated by -)|dev |pod |cluster.local|10.24.5.2 |

curl http://10-24-5-2.dev.pod.cluster.local

curl http://web-service.apps.svc.cluster.local

hostname.namespace.type. cluster.local

ex1: kubectl exec -it myapp-pod-2 nslookup 10-38-0-1.default.pod.cluster.local

ex2: kubectl exec -it myapp-pod-2 nslookup my-service.default.svc.cluster.local

Issue: nslookup for service/pod working when I use busybox:1.28, when i use any other image dns lookup not showing for service and Pod?
And does the jump pod have to be created before the desired service and Pod created ? or other way ?

2

This is a know bug in bussy box. Here are some tests:
busybox

/ # nslookup test-storag01.scm.svc.cluster.local
Server: 172.20.0.10
Address: 172.20.0.10:53

*** Can’t find test-storag01.scm.svc.cluster.local: No answer

Here is same test using a centos7 image:

nslookup test-storag01.scm.svc.cluster.local
Server: 172.20.0.10
Address: 172.20.0.10#53

Name: test-storag01.scm.svc.cluster.local
Address: 172.20.123.127

3

Thanks for the help, now it makes sense to me.
Can you also please help me with this
in many practice questions I am asked to fix broken cluster, but could not figure out most of the times. not sure what are the possible things for this issue .

kubectl cluster-info
the connection to the server localhost:6443 was refused. I checked kubectl config view, it has the right info of user and api server.