Error registering network: failed to acquire lease: subnet "10.244.0.0/16" specified in the flannel net config doesn't contain "192.168.0.0/24" PodCIDR of the "master node" node

증상: flannel pod 및 coredns pod가 기동하지 못함

kubectl logs -f pod/{pod} -n kube-flannel

원인: Flannel이 예상하는  IP(10.244.0.0/16)가 설정되지 않음

조치: k8s 재설정

sudo kubeadm reset -f
sudo rm -rf /etc/kubernetes /var/lib/etcd ~/.kube

# 살아 있는 port 확인
sudo netstat -tulnp | grep -E '6443|10259|10257|10250|2379|2380'


sudo systemctl stop kubelet
sudo systemctl stop docker  # or containerd
sudo systemctl restart kubelet

sudo systemctl restart docker # or containerd
sudo systemctl restart kubelet

sudo kubeadm init --pod-network-cidr=10.244.0.0/16

mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

# 실행하고 좀 기다려야 함
kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

# 확인
kubectl get pods -A