【k8s-4】kubeadm init的使用

【k8s-4】kubeadm init的使用

第一次执行 kubeadm init 报错了，具体看看怎么处理。

# kubeadm init
[init] Using Kubernetes version: v1.22.3
[preflight] Running pre-flight checks
	[WARNING Service-Docker]: docker service is not enabled, please run 'systemctl enable docker.service'
error execution phase preflight: [preflight] Some fatal errors occurred:
	[ERROR FileContent--proc-sys-net-ipv4-ip_forward]: /proc/sys/net/ipv4/ip_forward contents are not set to 1
[preflight] If you know what you are doing, you can make a check non-fatal with `--ignore-preflight-errors=...`
To see the stack trace of this error execute with --v=5 or higher

docker 的 service 没有置为 enable，设置好就行了。另外关于 ipv4 通过 echo 1 > /proc/sys/net/ipv4/ip_forward 就可以了，这里的意思是是否打开 ip 转发。

[root@VM-23-61-centos ~]# echo "1" > /proc/sys/net/ipv4/ip_forward
[root@VM-23-61-centos ~]# service network restart
Restarting network (via systemctl):                        [  OK  ]

通过 ps -ef|grep -i docker 可以看到下面的进程。

docker pull k8s.gcr.io/kube-apiserver:v1.22.3

意思就是 kubeadm init 调用 docker 在拉取镜像。

但是你以为在拉，但实际 docker images 都找不到镜像啊，查看 docker.service 的日志发现还有些报错。

没办法，还是基本都超时，想想办法替换一下配置文件的仓库源看看。

从日志看，需要拉取下面几个镜像。

I1030 15:05:58.040211  181596 checks.go:855] pulling: k8s.gcr.io/kube-apiserver:v1.22.3
I1030 15:07:13.314043  181596 checks.go:855] pulling: k8s.gcr.io/kube-controller-manager:v1.22.3
I1030 15:08:28.598273  181596 checks.go:855] pulling: k8s.gcr.io/kube-scheduler:v1.22.3
I1030 15:09:43.864626  181596 checks.go:855] pulling: k8s.gcr.io/kube-proxy:v1.22.3
I1030 15:10:59.142041  181596 checks.go:855] pulling: k8s.gcr.io/pause:3.5
I1030 15:12:14.433512  181596 checks.go:855] pulling: k8s.gcr.io/etcd:2.5.0-0
I1030 15:13:29.702488  181596 checks.go:855] pulling: k8s.gcr.io/coredns/coredns:v1.8.4

所以执行下面的命令，先拉取镜像，再重新打 tag。

docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.22.3
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:v1.22.3
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:v1.22.3
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.22.3
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.5
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.5.0-0
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:v1.8.4

docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver:v1.22.3 k8s.gcr.io/kube-apiserver:v1.22.3
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager:v1.22.3 k8s.gcr.io/kube-controller-manager:v1.22.3
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler:v1.22.3 k8s.gcr.io/kube-scheduler:v1.22.3
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy:v1.22.3 k8s.gcr.io/kube-proxy:v1.22.3
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.5 k8s.gcr.io/pause:3.5
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/etcd:3.5.0-0 k8s.gcr.io/etcd:3.5.0-0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/coredns:v1.8.4 k8s.gcr.io/coredns/coredns:v1.8.4

然后再执行 kubeadm init 就会得到镜像已经下载好的提示。

I1030 22:53:56.634982  398832 checks.go:838] using image pull policy: IfNotPresent
I1030 22:53:56.662771  398832 checks.go:847] image exists: k8s.gcr.io/kube-apiserver:v1.22.3
I1030 22:53:56.689402  398832 checks.go:847] image exists: k8s.gcr.io/kube-controller-manager:v1.22.3
I1030 22:53:56.717194  398832 checks.go:847] image exists: k8s.gcr.io/kube-scheduler:v1.22.3
I1030 22:53:56.743029  398832 checks.go:847] image exists: k8s.gcr.io/kube-proxy:v1.22.3
I1030 22:53:56.770703  398832 checks.go:847] image exists: k8s.gcr.io/pause:3.5
I1030 22:53:56.798320  398832 checks.go:847] image exists: k8s.gcr.io/etcd:3.5.0-0
I1030 22:53:56.824973  398832 checks.go:847] image exists: k8s.gcr.io/coredns/coredns:v1.8.4