1、节点状态NotReady

无论使用kubeadm init 初始化的节点，还是通过kubeadm join添加的节点，通过kubectl get node命令查看状态列都是NotReady状态。

第一步先为节点安装网络插件calico或者flannel，安装方法在上一节提到过，这里不做赘述。

安装网络插件的过程中发现，状态始终不变化，使用kubectl get pod -n kube-system命令查看，状态栏会出现 ImagePullBackOff 状态

NAME                                       READY   STATUS    RESTARTS   AGE
calico-kube-controllers-66956989f4-94872   1/1     Running   0          16h
calico-node-46pcm                          1/1     Running   1          56d
calico-node-dt6pv                          1/1     Running   2          56d
calico-node-g7cpw                          1/1     ImagePullBackOff 0   10h
calico-node-glzzp                          0/1     Running   0          20d
calico-node-kz2l8                          1/1     Running   0          3d10h
calico-node-ljr74                          1/1     Running   2          90d
coredns-74ff55c5b-7q9tx                    1/1     Running   0          16h
coredns-74ff55c5b-8tq4m                    1/1     Running   0          16h
etcd-k8s70131                              1/1     Running   0          2d23h

使用kubectl describe pod calico-node-g7cpw    -n kube-system命令查看，会出现 “k8s.gcr.io/” 的字样，这里红色部分是pod的名，根据实际名填写。

Events:
  Type     Reason                  Age                 From     Message
  ----     ------                  ----                ----     -------
  Warning  FailedCreatePodSandBox  29s (x3 over 102s)  kubelet  Failed to create pod 
sandbox: rpc error: code = Unknown desc = failed pulling image "k8s.gcr.io/pause:3.4.1": 
Error response from daemon: Get https://k8s.gcr.io/v2/: net/http: request canceled while
 waiting for connection (Client.Timeout exceeded while awaiting headers)

这是因为k8s通过kubeadm安装时需要通过docker拉取镜像，并且拉取下来的镜像标签必须是要和

kubeadm config images list

中的内容保持一致才能正确安装。

首先可以使用sudo docker images 命令看看本机有没有上述命令列表中的镜像，如果没有手动拉取。

这里注意一点，查看的节点位置。可以通过kubectl get pod -n kube-system -o wide 来看问题节点的ip，查看docker 镜像的节点位置是问题节点对应的ip主机。

NAME                                       READY   STATUS    RESTARTS   AGE     IP             NODE       NOMINATED NODE   READINESS GATES
calico-kube-controllers-66956989f4-94872   1/1     Running   0          16h     22.244.11.68   k8s70134   <none>           <none>
calico-node-46pcm                          1/1     Running   1          56d     10.12.70.133   k8s70133   <none>           <none>
calico-node-dt6pv                          1/1     ImagePullBackOff   2  56d     10.12.70.132   k8s70132   <none>           <none>

第二步，手动拉取镜像

通过kubeadm config images list命令查看，需要拉取如下镜像

k8s.gcr.io/kube-apiserver:v1.21.2
k8s.gcr.io/kube-controller-manager:v1.21.2
k8s.gcr.io/kube-scheduler:v1.21.2
k8s.gcr.io/kube-proxy:v1.21.2
k8s.gcr.io/pause:3.4.1
k8s.gcr.io/etcd:3.4.13-0
k8s.gcr.io/coredns/coredns:v1.8.0

因为k8s.gcr.io镜像库在国内需要翻墙，所以普通下载无法成功完成，可以更改一下下载的镜像库地址为国内地址，下载后将标签打回和kubeadm config一致的方法解决。

vim pullk8s.sh

for i in `kubeadm config images list`; do
        imageName=${i#k8s.gcr.io/}
        docker pull registry.aliyuncs.com/google_containers/$imageName
        docker tag registry.aliyuncs.com/google_containers/$imageName k8s.gcr.io/$imageName
        docker rmi registry.aliyuncs.com/google_containers/$imageName
done;

此时查看docker images

REPOSITORY                           TAG        IMAGE ID       CREATED         SIZE
haproxy                              latest     b68c771805b9   5 weeks ago     95.3MB
haproxy                              <none>     058875cd29c9   2 months ago    93.8MB
haproxy                              <none>     41c279cc8186   3 months ago    93.7MB
traefik                              latest     04ba4339d48a   3 months ago    95.2MB
calico/node                          v3.17.3    a45c42ebe880   4 months ago    165MB
calico/pod2daemon-flexvol            v3.17.3    53f21afd77e8   4 months ago    21.7MB
calico/cni                           v3.17.3    32eddea2c8b4   4 months ago    128MB
k8s.gcr.io/kube-proxy                v1.20.4    c29e6c583067   4 months ago    118MB
k8s.gcr.io/kube-controller-manager   v1.20.4    0a41a1414c53   4 months ago    116MB
k8s.gcr.io/kube-apiserver            v1.20.4    ae5eb22e4a9d   4 months ago    122MB
k8s.gcr.io/kube-scheduler            v1.20.4    5f8cb769bd73   4 months ago    47.3MB
haproxy                              <none>     112ff8b8991a   4 months ago    94.3MB
k8s.gcr.io/etcd                      3.4.13-0   0369cf4303ff   9 months ago    253MB
k8s.gcr.io/coredns                   1.7.0      bfe3a36ebd25   12 months ago   45.2MB
osixia/keepalived                    stable     d04966a100a7   15 months ago   72.9MB
k8s.gcr.io/pause                     3.2        80d28bedfe5d   16 months ago   683kB

这样等待一会后，在使用kubectl get pod -n kube-system查看状态都是Running就说明安装正常了。