IPVS mode NodeLocal DNSCache

Reduce cluster DNS load by adding NodeLocal DNSCache on every node.

• Download template file from:
  https://github.com/kubernetes/kubernetes/blob/master/cluster/addons/dns/nodelocaldns/nodelocaldns.yaml
• Create this bash script (don’t forget to change kubedns,domain,localdns variables)

#!/bin/bash
cd $(dirname $0)
wget -q -O nodelocaldns.yaml https://raw.githubusercontent.com/kubernetes/kubernetes/master/cluster/addons/dns/nodelocaldns/nodelocaldns.yaml
kubedns=$(kubectl get svc kube-dns -n kube-system -o jsonpath={.spec.clusterIP})
domain=cluster.local
localdns=169.254.20.53
echo ""
echo kubedns=$kubedns
echo domain=$domain
echo localdns=$localdns
echo ""
echo -n "Continue ?"
read a
cat << EOF > run.sh
#sed -i "s/__PILLAR__LOCAL__DNS__/$localdns/g; s/__PILLAR__DNS__DOMAIN__/$domain/g; s/,__PILLAR__DNS__SERVER__//g; s/__PILLAR__CLUSTER__DNS__/$kubedns/g" nodelocaldns.yaml
sed  "s/__PILLAR__LOCAL__DNS__/$localdns/g; s/__PILLAR__DNS__DOMAIN__/$domain/g; s/,__PILLAR__DNS__SERVER__//g; s/__PILLAR__CLUSTER__DNS__/$kubedns/g" nodelocaldns.yaml
rm -rf \$0
EOF
bash ./run.sh > nodelocaldns_deploy.yaml

• Remove excess comma on line: 146 and run

kubectl apply-f nodelocaldns_ipvs_ready.yaml

• Update kubelet configuration file: /var/lib/kubelet/config.yaml on every node

clusterDNS:
- 169.254.20.53

• Restart kubelet or restart just node

$ kubectl get ds -n kube-system 
NAME             DESIRED   CURRENT   READY   UP-TO-DATE   AVAILABLE   
kube-proxy       4         4         4       4            4           
node-local-dns   4         4         4       4            4           
weave-net        4         4         4       4            4

Done.
refer : https://kubernetes.io/docs/tasks/administer-cluster/nodelocaldns/

edit1: fixed error on the script, can not recall why I did it wrong way.