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I have kubernetes cluster running on 4 Raspberry-pi devices, out of which 1 is acting as master and other 3 are working as worker i.e w1, w2, w3. I have started a daemon set deployment, so each worker is running a pod of 2 containers.

w2 is running pod of 2 container. If I exec into any container and ping www.google.com from the container, I get the response. But if I do the same on w1 and w3 it says temporary failure in name resolution. All the pods in kube-system are running. I am using weave for networking. Below are all the pods for kube-system

NAME READY STATUS RESTARTS AGE
etcd-master-pi 1/1 Running 1 23h
kube-apiserver-master-pi 1/1 Running 1 23h
kube-controller-manager-master-pi 1/1 Running 1 23h
kube-dns-7b6ff86f69-97vtl 3/3 Running 3 23h
kube-proxy-2tmgw 1/1 Running 0 14m
kube-proxy-9xfx9 1/1 Running 2 22h
kube-proxy-nfgwg 1/1 Running 1 23h
kube-proxy-xbdxl 1/1 Running 3 23h
kube-scheduler-master-pi 1/1 Running 1 23h
weave-net-7sh5n 2/2 Running 1 14m
weave-net-c7x8p 2/2 Running 3 23h
weave-net-mz4c4 2/2 Running 6 22h
weave-net-qtgmw 2/2 Running 10 23h

If I am starting the containers using the normal docker container command but not from the kubernetes deployment then I do not see this issue. I think this is because of kube-dns. How can I debug this issue.?

You can start by checking if the dns is working

Run the nslookup on kubernetes.default from inside the pod, check if it is working.

[root@metrics-master-2 /]# nslookup kubernetes.default
Server: 10.96.0.10
Address: 10.96.0.10#53

Name: kubernetes.default.svc.cluster.local
Address: 10.96.0.1

Check the local dns configuration inside the pods:

[root@metrics-master-2 /]# cat /etc/resolv.conf 
nameserver 10.96.0.10
search default.svc.cluster.local svc.cluster.local cluster.local ec2.internal
options ndots:5

At last, check the kube-dns container logs while you run the ping command, It will give you the possible reasons why the name is not resolving.

kubectl logs kube-dns-86f4d74b45-7c4ng -c kubedns -n kube-system

Hope this helps.