Calico as the overlay network policy plugin, plays a vital role in the cluster communications.

Install calicoctl

The easiest form of accessing the calico manifest store is using calicoctl in the controller pod:

# exec into calico-controller container of the cluster
kubectl exec -n kube-system -t -i $(kubectl get pods -n kube-system -l k8s-app=calico-policy -o go-template='{{range .items}}{{}}{{end}}') /bin/sh

# download calicoctl
apk --update add curl
curl -O -L
chmod +x calicoctl

# request node objects
./calicoctl get nodes

# leave container