k8s 拉取镜像失败_惊呆了！部署k8s集群竟如此简单，手把手教你部署集群

左手的ㄟ右手 2023-01-04 13:10 1022阅读 0赞

![772cd11eeb7e2c8dabf62b986b4b9e4e.png][]

## kubernetes集群部署 ##

**为节约资源此集群仅3台机器**

方式1. minikube

> Minikube是一个工具，可以在本地快速运行一个单点的Kubernetes，尝试Kubernetes或日常开发的用户使用。不能用于生产环境。  
> 官方地址： https:// kubernetes.io/docs/setu p/minikube/

方式2. kubeadm

> Kubeadm也是一个工具，提供kubeadm init和kubeadm join，用于快速部署Kubernetes集群。  
> 官方地址： https:// kubernetes.io/docs/refe rence/setup-tools/kubeadm/kubeadm/

方式3. 直接使用epel-release yum源，缺点就是版本较低 1.5

方式4. 二进制包

> 从官方下载发行版的二进制包，手动部署每个组件，组成Kubernetes集群。

其他的开源工具：

> https:// docs.kubeoperator.io/ku beoperator-v2.2/introduction

### 二、kubeadm部署k8s集群 ###

官方文档：

https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/install-kubeadm/

kubeadm部署k8s高可用集群的官方文档：

https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/high-availability/

**注：本文采用最新版centos版本8.1**

### **1、系统配置** ###

### **1.1、集群环境** ###

**机器数量**

> 3台

**操作系统**

> Centos8.1

**设置主机名称**

> 分别设置主机名称为：  
> master node1 node2

**每台机器必须设置域名解析**

> 192.168.1.200 master  
> 192.168.1.201 node1  
> 192.168.1.202 node2

### **1.2、禁用开机启动防火墙** ###

# systemctl disable firewalld

### **1.3、永久禁用SELinux** ###

编辑文件/etc/selinux/config，将SELINUX修改为disabled，如下：

# sed -i 's/SELINUX=permissive/SELINUX=disabled/' /etc/sysconfig/selinux
    SELINUX=disabled

### **1.4、关闭系统Swap** ###

1.8版本之后的新规定

Kubernetes 1.8开始要求关闭系统的Swap，如果不关闭，默认配置下kubelet将无法启动。

> 修改/etc/fstab文件，注释掉SWAP的自动挂载，使用free -m确认swap已经关闭。

[root@master /]# sed -i 's/.*swap.*/#&/' /etc/fstab
    #/dev/mapper/centos-swap swap  swap   defaults     0 0

### **1.5、检查MAC地址和product\_uuid** ###

Verify the MAC address and product\_uuid are unique for every node

*  You can get the MAC address of the network interfaces using the command  
    \# ip link
 *  The product\_uuid can be checked by using the command  
    \# cat /sys/class/dmi/id/product\_uuid

It is very likely that hardware devices will have unique addresses, although some virtual machines may have identical values. Kubernetes uses these values to uniquely identify the nodes in the cluster. If these values are not unique to each node, the installation process may fail.

### **1.6、重启系统** ###

### **2、安装软件** ###

### **2.1 所有机器安装docker** ###

# yum install wget container-selinux -y
    # wget https://download.docker.com/linux/centos/7/x86_64/stable/Packages/containerd.io-1.2.6-3.3.el7.x86_64.rpm
    # yum erase runc -y
    # rpm -ivh containerd.io-1.2.6-3.3.el7.x86_64.rpm
    注意：上面的步骤在centos7中无须操作
    # update-alternatives --set iptables /usr/sbin/iptables-legacy
    # yum install -y yum-utils device-mapper-persistent-data lvm2 && yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo && yum makecache && yum -y install docker-ce -y && systemctl enable docker.service && systemctl start docker

### **2.2 所有机器安装kubeadm和kubelet** ###

**配置aliyun的yum源**

# cat <<EOF > /etc/yum.repos.d/kubernetes.repo
    [kubernetes]
    name=Kubernetes
    baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
    enabled=1
    gpgcheck=1
    repo_gpgcheck=1
    gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
    EOF

**安装最新版kubeadm**

# yum makecache
    # yum install -y kubelet kubeadm kubectl ipvsadm
    
    说明：如果想安装指定版本的kubeadmin
    #yum install kubelet-1.16.0-0.x86_64 kubeadm-1.16.0-0.x86_64 kubectl-1.16.0-0.x86_64

**配置内核参数**

# cat <<EOF >  /etc/sysctl.d/k8s.conf
    net.bridge.bridge-nf-call-ip6tables = 1
    net.bridge.bridge-nf-call-iptables = 1
    vm.swappiness=0
    EOF
    
    # sysctl --system
    # modprobe br_netfilter
    # sysctl -p /etc/sysctl.d/k8s.conf
    
    加载ipvs相关内核模块
    如果重新开机，需要重新加载（可以写在 /etc/rc.local 中开机自动加载）
    # modprobe ip_vs
    # modprobe ip_vs_rr
    # modprobe ip_vs_wrr
    # modprobe ip_vs_sh
    # modprobe nf_conntrack_ipv4
    
    查看是否加载成功
    # lsmod | grep ip_vs

### **3、获取镜像** ###

**特别说明：**

*  **三个节点都要下载**
 *  **注意下载时把版本号修改到官方最新版，即使下载了最新版也可能版本不对应，需要按报错提示下载**
 *  **每次部署都会有版本更新，具体版本要求，运行初始化过程失败会有版本提示**
 *  **kubeadm的版本和镜像的版本必须是对应的****用命令查看版本当前kubeadm对应的k8s镜像版本**  
    \[root@master ~\]\# kubeadm config images listhttp://k8s.gcr.io/kube-apiserver:v1.17.2http://k8s.gcr.io/kube-controller-manager:v1.17.2http://k8s.gcr.io/kube-scheduler:v1.17.2http://k8s.gcr.io/kube-proxy:v1.17.2http://k8s.gcr.io/pause:3.1http://k8s.gcr.io/etcd:3.4.3-0http://k8s.gcr.io/coredns:1.6.5**使用下面的方法在aliyun拉取相应的镜像并重新打标**

> docker pull http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-apiserver:v1.17.2  
> docker tag http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-apiserver:v1.17.2 http:// k8s.gcr.io/kube-apiserv er:v1.17.2  
> docker pull http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-controller-manager:v1.17.2  
> docker tag http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-controller-manager:v1.17.2 http:// k8s.gcr.io/kube-control ler-manager:v1.17.2  
> docker pull http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-scheduler:v1.17.2  
> docker tag http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-scheduler:v1.17.2 http:// k8s.gcr.io/kube-schedul er:v1.17.2  
> docker pull http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-proxy:v1.17.2  
> docker tag http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/kube-proxy:v1.17.2 http:// k8s.gcr.io/kube-proxy:v 1.17.2  
> docker pull http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/pause:3.1  
> docker tag http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/pause:3.1 http:// k8s.gcr.io/pause:3.1  
> docker pull http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/etcd:3.4.3-0  
> docker tag http:// registry.cn-hangzhou.aliyuncs.com /google\_containers/etcd:3.4.3-0 http:// k8s.gcr.io/etcd:3.4.3-0  
> docker pull coredns/coredns:1.6.5  
> docker tag coredns/coredns:1.6.5 http:// k8s.gcr.io/coredns:1.6. 5

**下图是2019-12-11的版本1.17.0的下载列表**

![44dd370d836709db3fad83e5805fa8b1.png][]

# docker images
    REPOSITORY              TAG                 IMAGE ID                    CREATED                     SIZE
    k8s.gcr.io/kube-proxy   v1.17.0       7d54289267dc    Less than a second ago  116MB
    
    registry.cn-hangzhou.aliyuncs.com/google_containers/kube-proxy  v1.17.0 7d54289267dc  Less than a second ago  116MB
    
    k8s.gcr.io/kube-controller-manager v1.17.0 5eb3b7486872  Less than a second ago  161MB
    
    registry.cn-hangzhou.aliyuncs.com/google_containers/kube-controller-manager v1.17.0  5eb3b7486872    Less than a second ago  161MB
    
    registry.cn-hangzhou.aliyuncs.com/google_containers/kube-scheduler v1.17.0 78c190f736b1    Less than a second ago  94.4MB
    
    k8s.gcr.io/kube-scheduler       v1.17.0     78c190f736b1    Less than a second ago  94.4MB
    
    k8s.gcr.io/kube-apiserver       v1.17.0     0cae8d5cc64c    Less than a second ago  171MB
    
    registry.cn-hangzhou.aliyuncs.com/google_containers/kube-apiserver  v1.17.0 0cae8d5cc64c    Less than a second ago  171MB
    
    registry.cn-hangzhou.aliyuncs.com/google_containers/coredns 1.6.5 70f311871ae1 7 days ago        41.6MB
    
    k8s.gcr.io/coredns 1.6.5  70f311871ae1    7 days ago        41.6MB
    
    k8s.gcr.io/etcd  3.4.3-0  303ce5db0e90    2 weeks ago       288MB
    
    registry.cn-hangzhou.aliyuncs.com/google_containers/etcd 3.4.3 303ce5db0e90 2 weeks ago       288MB
    
    quay.io/coreos/flannel v0.11.0-amd6

### **4、所有节点配置启动kubelet** ###

### **4.1、配置kubelet使用国内pause镜像** ###

**获取docker的cgroups**

DOCKER_CGROUPS=$(docker info | grep 'Cgroup' | cut -d' ' -f4)
    # echo $DOCKER_CGROUPS
    cgroupfs

**配置kubelet的cgroups**

cat >/etc/sysconfig/kubelet<<EOF
    KUBELET_EXTRA_ARGS="--cgroup-driver=$DOCKER_CGROUPS --pod-infra-container-image=k8s.gcr.io/pause:3.1"
    EOF

### **4.2、启动** ###

# systemctl daemon-reload
    # systemctl enable kubelet && systemctl start kubelet

**特别说明：在这里使用systemctl status kubelet，你会发现报错误信息**

> 10月 11 00:26:43 node1 systemd\[1\]: kubelet.service: main process exited, code=exited, status=255/n/a  
> 10月 11 00:26:43 node1 systemd\[1\]: Unit kubelet.service entered failed state.  
> 10月 11 00:26:43 node1 systemd\[1\]: kubelet.service failed.  
> 运行journalctl -xefu kubelet 命令查看systemd日志才发现，真正的错误是：  
> unable to load client CA file /etc/kubernetes/pki/ca.crt: open /etc/kubernetes/pki/ca.crt: no such file or directory  
> 这个错误在运行kubeadm init 生成CA证书后会被自动解决，此处可先忽略。  
> 简单地说就是在kubeadm init 之前kubelet会不断重启。

### **5、初始化集群** ###

### **5.1、在master节点进行初始化操作** ###

特别说明：

> 初始化完成必须要记录下初始化过程最后的命令，如下图所示

![b1ca830c635ea4e85286b5f3bd2ca480.png][]

[root@master ～# kubeadm init --kubernetes-version=v1.17.2 --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=192.168.1.200 --ignore-preflight-errors=Swap
    
    [init] Using Kubernetes version: v1.1.0
    [preflight] Running pre-flight checks
        [WARNING SystemVerification]: this Docker version is not on the list of validated versions: 18.09.1. Latest validated version: 18.06
    [preflight] Pulling images required for setting up a Kubernetes cluster
    [preflight] This might take a minute or two, depending on the speed of your internet connection
    [preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
    
    [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
    [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
    [kubelet-start] Activating the kubelet service
    [certs] Using certificateDir folder "/etc/kubernetes/pki"
    [certs] Generating "front-proxy-ca" certificate and key
    [certs] Generating "front-proxy-client" certificate and key
    [certs] Generating "etcd/ca" certificate and key
    [certs] Generating "etcd/server" certificate and key
    [certs] etcd/server serving cert is signed for DNS names [master localhost] and IPs [192.168.1.200 127.0.0.1 ::1]
    [certs] Generating "etcd/healthcheck-client" certificate and key
    [certs] Generating "etcd/peer" certificate and key
    [certs] etcd/peer serving cert is signed for DNS names [master localhost] and IPs [192.168.1.200 127.0.0.1 ::1]
    [certs] Generating "apiserver-etcd-client" certificate and key
    [certs] Generating "ca" certificate and key
    [certs] Generating "apiserver" certificate and key
    [certs] apiserver serving cert is signed for DNS names [master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.1.200]
    [certs] Generating "apiserver-kubelet-client" certificate and key
    [certs] Generating "sa" key and public key
    [kubeconfig] Using kubeconfig folder "/etc/kubernetes"
    [kubeconfig] Writing "admin.conf" kubeconfig file
    [kubeconfig] Writing "kubelet.conf" kubeconfig file
    [kubeconfig] Writing "controller-manager.conf" kubeconfig file
    [kubeconfig] Writing "scheduler.conf" kubeconfig file
    [control-plane] Using manifest folder "/etc/kubernetes/manifests"
    [control-plane] Creating static Pod manifest for "kube-apiserver"
    [control-plane] Creating static Pod manifest for "kube-controller-manager"
    [control-plane] Creating static Pod manifest for "kube-scheduler"
    [etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
    [wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
    [apiclient] All control plane components are healthy after 19.003093 seconds
    [uploadconfig] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
    [kubelet] Creating a ConfigMap "kubelet-config-1.13" in namespace kube-system with the configuration for the kubelets in the cluster
    [patchnode] Uploading the CRI Socket information "/var/run/dockershim.sock" to the Node API object "master" as an annotation
    [mark-control-plane] Marking the node master as control-plane by adding the label "node-role.kubernetes.io/master=''"
    [mark-control-plane] Marking the node master as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
    [bootstrap-token] Using token: wip0ux.19q3dpudrnyc6q7i
    [bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
    [bootstraptoken] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
    [bootstraptoken] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
    [bootstraptoken] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
    [bootstraptoken] creating the "cluster-info" ConfigMap in the "kube-public" namespace
    [addons] Applied essential addon: CoreDNS
    [addons] Applied essential addon: kube-proxy
    
    Your Kubernetes master has initialized successfully!
    
    To start using your cluster, you need to run the following as a regular user:
     mkdir -p $HOME/.kube
     sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
     sudo chown $(id -u):$(id -g) $HOME/.kube/config
    
    You should now deploy a pod network to the cluster.
    
    Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
     https://kubernetes.io/docs/concepts/cluster-administration/addons/
    
    You can now join any number of machines by running the following on each node
    as root:
     kubeadm join 192.168.1.200:6443 --token wip0ux.19q3dpudrnyc6q7i --discovery-token-ca-cert-hash sha256:e41c201f32d7aa6c57254cd78c13a5aa7242979f7152bf33ec25dde13c1dcc9a

上面记录了完成的初始化输出的内容，根据输出的内容基本上可以看出手动初始化安装一个Kubernetes集群所需要的关键步骤。

其中有以下关键内容：

> \[kubelet\] 生成kubelet的配置文件”/var/lib/kubelet/config.yaml”  
> \[certificates\]生成相关的各种证书  
> \[kubeconfig\]生成相关的kubeconfig文件  
> \[bootstraptoken\]生成token记录下来，后边使用kubeadm join往集群中添加节点时会用到

### **5.2、在master节点配置使用kubectl** ###

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

### **5.3、查看node节点** ###

# kubectl get nodes
    NAME   STATUS   ROLES   AGE   VERSION
    master  NotReady  master  6m19s  v1.13.0

### **6、配置网络插件** ###

### **6.1、master节点下载yaml配置文件** ###

> 特别说明：版本会经常更新，如果配置成功，就手动去 https:// raw.githubusercontent.com /coreos/flannel/master/Documentation/ 下载最新版yaml文件

# cd ~ && mkdir flannel && cd flannel
    # curl -O https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

### **6.2、修改配置文件kube-flannel.yml** ###

> 说明：默认的镜像是 http:// quay.io/coreos/flannel: v0.10.0-amd64 ，如果你能pull下来就不用修改镜像地址，否则，修改yml中镜像地址为阿里镜像源,要修改所有的镜像版本，里面有好几条flannel镜像地址  
> image: http:// registry.cn-shanghai.aliyuncs.com /gcr-k8s/flannel:v0.10.0-amd64

**指定启动网卡**

flanneld启动参数加上--iface=<iface-name>

containers:
      - name: kube-flannel
        image: registry.cn-shanghai.aliyuncs.com/gcr-k8s/flannel:v0.10.0-amd64
        command:
        - /opt/bin/flanneld
    
        args:
        - --ip-masq
        - --kube-subnet-mgr
        - --iface=ens33
        - --iface=eth0

⚠️⚠️⚠️--iface=ens33 的值，是你当前的网卡,或者可以指定多网卡

**启动**

# kubectl apply -f ~/flannel/kube-flannel.yml

**查看**

# kubectl get pods --namespace kube-system
    NAME                             READY   STATUS    RESTARTS   AGE
    coredns-6955765f44-g767b         1/1     Running   0          14m
    coredns-6955765f44-l8zzs         1/1     Running   0          14m
    etcd-master                      1/1     Running   0          14m
    kube-apiserver-master            1/1     Running   0          14m
    kube-controller-manager-master   1/1     Running   0          14m
    kube-flannel-ds-amd64-qjpzg      1/1     Running   0          28s
    kube-proxy-zklq2                 1/1     Running   0          14m
    kube-scheduler-master            1/1     Running   0          14m
    
    # kubectl get service
    NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
    kubernetes   ClusterIP   10.96.0.1    <none>        443/TCP   14m
    
    # kubectl get svc --namespace kube-system
    NAME       TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)                  AGE
    kube-dns   ClusterIP   10.96.0.10   <none>        53/UDP,53/TCP,9153/TCP   15m

只有网络插件也安装配置完成之后，才能会显示为ready状态

### **7、配置所有node节点加入集群** ###

在所有node节点操作，此命令为初始化master成功后返回的结果

# kubeadm join 192.168.1.200:6443 --token ccxrk8.myui0xu4syp99gxu --discovery-token-ca-cert-hash sha256:e3c90ace969aa4d62143e7da6202f548662866dfe33c140095b020031bff2986

### **8、集群检测** ###

**查看pods**

> 说明：节点加入到集群之后需要等待几分钟再查看

# kubectl get pods -n kube-system
    NAME                                    READY  STATUS       RESTARTS  AGE
    coredns-6c66ffc55b-l76bq        1/1   Running       0      16m
    coredns-6c66ffc55b-zlsvh        1/1   Running       0      16m
    etcd-node1                          1/1   Running       0      16m
    kube-apiserver-node1            1/1   Running       0      16m
    kube-controller-manager-node1 1/1   Running         0      15m
    kube-flannel-ds-sr6tq           0/1   CrashLoopBackOff  6      7m12s
    kube-flannel-ds-ttzhv           1/1   Running       0      9m24s
    kube-proxy-nfbg2                1/1   Running       0      7m12s
    kube-proxy-r4g7b                1/1   Running       0      16m
    kube-scheduler-node1            1/1   Running       0      16m

**遇到异常状态0/1的pod长时间启动不了可删除它等待集群创建新的pod资源**

# kubectl delete pod kube-flannel-ds-sr6tq -n kube-system
    pod "kube-flannel-ds-sr6tq" deleted

**删除后再次查看，发现状态为正常**

[root@master flannel]# kubectl get pods -n kube-system
    NAME                             READY   STATUS    RESTARTS   AGE
    coredns-6955765f44-g767b         1/1     Running   0          18m
    coredns-6955765f44-l8zzs         1/1     Running   0          18m
    etcd-master                      1/1     Running   0          18m
    kube-apiserver-master            1/1     Running   0          18m
    kube-controller-manager-master   1/1     Running   0          18m
    kube-flannel-ds-amd64-bsdcr      1/1     Running   0          60s
    kube-flannel-ds-amd64-g8d7x      1/1     Running   0          2m33s
    kube-flannel-ds-amd64-qjpzg      1/1     Running   0          5m9s
    kube-proxy-5pmgv                 1/1     Running   0          2m33s
    kube-proxy-r962v                 1/1     Running   0          60s
    kube-proxy-zklq2                 1/1     Running   0          18m
    kube-scheduler-master            1/1     Running   0          18m

**再次查看节点状态**

[root@master flannel]# kubectl get nodes -n kube-system
    NAME     STATUS   ROLES    AGE     VERSION
    master   Ready    master   19m     v1.17.2
    node1    Ready    <none>   3m16s   v1.17.2
    node2    Ready    <none>   103s    v1.17.2

**到此集群配置完成**

[772cd11eeb7e2c8dabf62b986b4b9e4e.png]: /images/20221119/575b779491a84a91820d92646a0e9947.png
[44dd370d836709db3fad83e5805fa8b1.png]: https://img-blog.csdnimg.cn/img_convert/44dd370d836709db3fad83e5805fa8b1.png
[b1ca830c635ea4e85286b5f3bd2ca480.png]: https://img-blog.csdnimg.cn/img_convert/b1ca830c635ea4e85286b5f3bd2ca480.png