Centos7搭建k8s环境教程，一次性成功！ 转载：https://mp.weixin.qq.com/s/AdoZeoytJ1n2t1TPuLEuDQ

一. 为什么是k8s v1.16.0？

最新版的v1.16.2试过了，一直无法安装完成，安装到kubeadm init那一步执行后，报了很多错，如：node xxx not found等。centos7都重装了几次，还是无法解决。用了一天都没安装完，差点放弃。

后来在网上搜到的安装教程基本都是v1.16.0的，我不太相信是v1.16.2的坑所以先前没打算降级到v1.16.0。没办法了就试着安装v1.16.0版本，竟然成功了。记录在此，避免后来者踩坑。

本篇文章，安装大步骤如下：

• 安装docker-ce 18.09.9（所有机器）

• 设置k8s环境前置条件（所有机器）

• 安装k8s v1.16.0 master管理节点

• 安装k8s v1.16.0 node工作节点

• 安装flannel（master）

这里有重要的一步，请记住自己master和node之间通信的ip，如我的master的ip为192.168.99.104，node的ip为：192.168.99.105. 请确保使用这两个ip在master和node上能互相ping通，这个master的ip 192.168.99.104接下来配置k8s的时候需要用到。

我的环境：

• 操作系统：win10

• 虚拟机：virtual box

• linux发行版：CentOS7

• linux内核(使用uname -r查看)：3.10.0-957.el7.x86_64

• master和node节点通信的ip(master)：192.168.99.104

二. 安装docker-ce 18.09.9（所有机器）

所有安装k8s的机器都需要安装docker，命令如下：

# 安装docker所需的工具


yum install -y yum-utils device-mapper-persistent-data lvm2


# 配置阿里云的docker源


yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo


# 指定安装这个版本的docker-ce


yum install -y docker-ce-18.09.9-3.el7


# 启动docker


systemctl enable docker && systemctl start docker

三. 设置k8s环境准备条件（所有机器）

安装k8s的机器需要2个CPU和2g内存以上，这个简单，在虚拟机里面配置一下就可以了。然后执行以下脚本做一些准备操作。所有安装k8s的机器都需要这一步操作。

# 关闭防火墙


systemctl disable firewalld


systemctl stop firewalld


# 关闭selinux


# 临时禁用selinux


setenforce 0


# 永久关闭 修改/etc/sysconfig/selinux文件设置


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


sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config


# 禁用交换分区


swapoff -a


# 永久禁用，打开/etc/fstab注释掉swap那一行。


sed -i 's/.*swap.*/#&/' /etc/fstab


# 修改内核参数


cat <<EOF >  /etc/sysctl.d/k8s.conf


net.bridge.bridge-nf-call-ip6tables = 1


net.bridge.bridge-nf-call-iptables = 1


EOF


sysctl --system

四. 安装k8s v1.16.0 master管理节点

如果还没安装docker，请参照本文步骤二安装docker-ce 18.09.9（所有机器）安装。

如果没设置k8s环境准备条件，请参照本文步骤三设置k8s环境准备条件（所有机器）执行。

以上两个步骤检查完毕之后，继续以下步骤。

1. 安装kubeadm、kubelet、kubectl

由于官方k8s源在google，国内无法访问，这里使用阿里云yum源

# 执行配置k8s阿里云源


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kubeadm、kubectl、kubelet


yum install -y kubectl-1.16.0-0 kubeadm-1.16.0-0 kubelet-1.16.0-0


# 启动kubelet服务


systemctl enable kubelet && systemctl start kubelet

2. 初始化k8s

以下这个命令开始安装k8s需要用到的docker镜像，因为无法访问到国外网站，所以这条命令使用的是国内的阿里云的源

(registry.aliyuncs.com/google_containers)。

另一个非常重要的是：这里的--apiserver-advertise-address使用的是master和node间能互相ping通的ip，我这里是192.168.99.104，刚开始在这里被坑了一个晚上，你请自己修改下ip执行。

这条命令执行时会卡在[preflight] You can also perform this action in beforehand using ''kubeadm config images pull，大概需要2分钟，请耐心等待。

# 下载管理节点中用到的6个docker镜像，你可以使用docker images查看到


# 这里需要大概两分钟等待，会卡在[preflight] You can also perform this action in beforehand using ''kubeadm config images pull


kubeadm init --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.16.0 --apiserver-advertise-address 192.168.99.104 --pod-network-cidr=10.244.0.0/16 --token-ttl 0

上面安装完后，会提示你输入如下命令，复制粘贴过来，执行即可。

# 上面安装完成后，k8s会提示你输入如下命令，执行


mkdir -p $HOME/.kube


sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config


sudo chown $(id -u):$(id -g) $HOME/.kube/config

3. 记住node加入集群的命令

上面kubeadm init执行成功后会返回给你node节点加入集群的命令，等会要在node节点上执行，需要保存下来，如果忘记了，可以使用如下命令获取。

kubeadm token create --print-join-command 

以上，安装master节点完毕。可以使用kubectl get nodes查看一下，此时master处于NotReady状态，暂时不用管。

五. 安装k8s v1.16.0 node工作节点

如果还没安装docker，请参照本文步骤二安装docker-ce 18.09.9（所有机器）安装。

如果没设置k8s环境准备条件，请参照本文步骤三设置k8s环境准备条件（所有机器）执行。

以上两个步骤检查完毕之后，继续以下步骤。

1. 安装kubeadm、kubelet

# 执行配置k8s阿里云源


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kubeadm、kubectl、kubelet


yum install -y  kubeadm-1.16.0-0 kubelet-1.16.0-0


# 启动kubelet服务


systemctl enable kubelet && systemctl start kubelet

2. 加入集群

这里加入集群的命令每个人都不一样，可以登录master节点，使用kubeadm token create --print-join-command 来获取。获取后执行如下。

# 加入集群，如果这里不知道加入集群的命令，可以登录master节点，使用kubeadm token create --print-join-command 来获取 


kubeadm join 192.168.99.104:6443 --token ncfrid.7ap0xiseuf97gikl \


    --discovery-token-ca-cert-hash sha256:47783e9851a1a517647f1986225f104e81dbfd8fb256ae55ef6d68ce9334c6a2

加入成功后，可以在master节点上使用kubectl get nodes命令查看到加入的节点。

六. 安装flannel（master机器）

以上步骤安装完后，机器搭建起来了，但状态还是NotReady状态，如下图，master机器需要安装flanneld。

1. 下载官方fannel配置文件

使用wget命令，地址为：

(https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml)，这个地址国内访问不了，所以我把内容复制下来，为了避免前面文章过长，我把它粘贴到文章末尾第八个步骤附录了。

这个yml配置文件中配置了一个国内无法访问的地址(quay.io)，我已经将其改为国内可以访问的地址(quay-mirror.qiniu.com)。我们新建一个kube-flannel.yml文件，复制粘贴该内容即可。

2. 安装fannel

kubectl apply -f kube-flannel.yml

七. 大功告成

至此，k8s集群搭建完成，如下图节点已为Ready状态，大功告成，完结撒花。

八. 附录

这是kube-flannel.yml文件的内容，已经将无法访问的地址(quay.io)全部改为国内可以访问的地址(quay-mirror.qiniu.com)。我们新建一个kube-flannel.yml文件，复制粘贴该内容即可。

---


apiVersion: policy/v1beta1


kind: PodSecurityPolicy


metadata:


  name: psp.flannel.unprivileged


  annotations:


    seccomp.security.alpha.kubernetes.io/allowedProfileNames: docker/default


    seccomp.security.alpha.kubernetes.io/defaultProfileName: docker/default


    apparmor.security.beta.kubernetes.io/allowedProfileNames: runtime/default


    apparmor.security.beta.kubernetes.io/defaultProfileName: runtime/default


spec:


  privileged: false


  volumes:


    - configMap


    - secret


    - emptyDir


    - hostPath


  allowedHostPaths:


    - pathPrefix: "/etc/cni/net.d"


    - pathPrefix: "/etc/kube-flannel"


    - pathPrefix: "/run/flannel"


  readOnlyRootFilesystem: false


  # Users and groups


  runAsUser:


    rule: RunAsAny


  supplementalGroups:


    rule: RunAsAny


  fsGroup:


    rule: RunAsAny


  # Privilege Escalation


  allowPrivilegeEscalation: false


  defaultAllowPrivilegeEscalation: false


  # Capabilities


  allowedCapabilities: ['NET_ADMIN']


  defaultAddCapabilities: []


  requiredDropCapabilities: []


  # Host namespaces


  hostPID: false


  hostIPC: false


  hostNetwork: true


  hostPorts:


  - min: 0


    max: 65535


  # SELinux


  seLinux:


    # SELinux is unused in CaaSP


    rule: 'RunAsAny'


---


kind: ClusterRole


apiVersion: rbac.authorization.k8s.io/v1beta1


metadata:


  name: flannel


rules:


  - apiGroups: ['extensions']


    resources: ['podsecuritypolicies']


    verbs: ['use']


    resourceNames: ['psp.flannel.unprivileged']


  - apiGroups:


      - ""


    resources:


      - pods


    verbs:


      - get


  - apiGroups:


      - ""


    resources:


      - nodes


    verbs:


      - list


      - watch


  - apiGroups:


      - ""


    resources:


      - nodes/status


    verbs:


      - patch


---


kind: ClusterRoleBinding


apiVersion: rbac.authorization.k8s.io/v1beta1


metadata:


  name: flannel


roleRef:


  apiGroup: rbac.authorization.k8s.io


  kind: ClusterRole


  name: flannel


subjects:


- kind: ServiceAccount


  name: flannel


  namespace: kube-system


---


apiVersion: v1


kind: ServiceAccount


metadata:


  name: flannel


  namespace: kube-system


---


kind: ConfigMap


apiVersion: v1


metadata:


  name: kube-flannel-cfg


  namespace: kube-system


  labels:


    tier: node


    app: flannel


data:


  cni-conf.json: |


    {


      "name": "cbr0",


      "cniVersion": "0.3.1",


      "plugins": [


        {


          "type": "flannel",


          "delegate": {


            "hairpinMode": true,


            "isDefaultGateway": true


          }


        },


        {


          "type": "portmap",


          "capabilities": {


            "portMappings": true


          }


        }


      ]


    }


  net-conf.json: |


    {


      "Network": "10.244.0.0/16",


      "Backend": {


        "Type": "vxlan"


      }


    }


---


apiVersion: apps/v1


kind: DaemonSet


metadata:


  name: kube-flannel-ds-amd64


  namespace: kube-system


  labels:


    tier: node


    app: flannel


spec:


  selector:


    matchLabels:


      app: flannel


  template:


    metadata:


      labels:


        tier: node


        app: flannel


    spec:


      affinity:


        nodeAffinity:


          requiredDuringSchedulingIgnoredDuringExecution:


            nodeSelectorTerms:


              - matchExpressions:


                  - key: beta.kubernetes.io/os


                    operator: In


                    values:


                      - linux


                  - key: beta.kubernetes.io/arch


                    operator: In


                    values:


                      - amd64


      hostNetwork: true


      tolerations:


      - operator: Exists


        effect: NoSchedule


      serviceAccountName: flannel


      initContainers:


      - name: install-cni


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-amd64


        command:


        - cp


        args:


        - -f


        - /etc/kube-flannel/cni-conf.json


        - /etc/cni/net.d/10-flannel.conflist


        volumeMounts:


        - name: cni


          mountPath: /etc/cni/net.d


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      containers:


      - name: kube-flannel


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-amd64


        command:


        - /opt/bin/flanneld


        args:


        - --ip-masq


        - --kube-subnet-mgr


        resources:


          requests:


            cpu: "100m"


            memory: "50Mi"


          limits:


            cpu: "100m"


            memory: "50Mi"


        securityContext:


          privileged: false


          capabilities:


            add: ["NET_ADMIN"]


        env:


        - name: POD_NAME


          valueFrom:


            fieldRef:


              fieldPath: metadata.name


        - name: POD_NAMESPACE


          valueFrom:


            fieldRef:


              fieldPath: metadata.namespace


        volumeMounts:


        - name: run


          mountPath: /run/flannel


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      volumes:


        - name: run


          hostPath:


            path: /run/flannel


        - name: cni


          hostPath:


            path: /etc/cni/net.d


        - name: flannel-cfg


          configMap:


            name: kube-flannel-cfg


---


apiVersion: apps/v1


kind: DaemonSet


metadata:


  name: kube-flannel-ds-arm64


  namespace: kube-system


  labels:


    tier: node


    app: flannel


spec:


  selector:


    matchLabels:


      app: flannel


  template:


    metadata:


      labels:


        tier: node


        app: flannel


    spec:


      affinity:


        nodeAffinity:


          requiredDuringSchedulingIgnoredDuringExecution:


            nodeSelectorTerms:


              - matchExpressions:


                  - key: beta.kubernetes.io/os


                    operator: In


                    values:


                      - linux


                  - key: beta.kubernetes.io/arch


                    operator: In


                    values:


                      - arm64


      hostNetwork: true


      tolerations:


      - operator: Exists


        effect: NoSchedule


      serviceAccountName: flannel


      initContainers:


      - name: install-cni


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-arm64


        command:


        - cp


        args:


        - -f


        - /etc/kube-flannel/cni-conf.json


        - /etc/cni/net.d/10-flannel.conflist


        volumeMounts:


        - name: cni


          mountPath: /etc/cni/net.d


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      containers:


      - name: kube-flannel


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-arm64


        command:


        - /opt/bin/flanneld


        args:


        - --ip-masq


        - --kube-subnet-mgr


        resources:


          requests:


            cpu: "100m"


            memory: "50Mi"


          limits:


            cpu: "100m"


            memory: "50Mi"


        securityContext:


          privileged: false


          capabilities:


             add: ["NET_ADMIN"]


        env:


        - name: POD_NAME


          valueFrom:


            fieldRef:


              fieldPath: metadata.name


        - name: POD_NAMESPACE


          valueFrom:


            fieldRef:


              fieldPath: metadata.namespace


        volumeMounts:


        - name: run


          mountPath: /run/flannel


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      volumes:


        - name: run


          hostPath:


            path: /run/flannel


        - name: cni


          hostPath:


            path: /etc/cni/net.d


        - name: flannel-cfg


          configMap:


            name: kube-flannel-cfg


---


apiVersion: apps/v1


kind: DaemonSet


metadata:


  name: kube-flannel-ds-arm


  namespace: kube-system


  labels:


    tier: node


    app: flannel


spec:


  selector:


    matchLabels:


      app: flannel


  template:


    metadata:


      labels:


        tier: node


        app: flannel


    spec:


      affinity:


        nodeAffinity:


          requiredDuringSchedulingIgnoredDuringExecution:


            nodeSelectorTerms:


              - matchExpressions:


                  - key: beta.kubernetes.io/os


                    operator: In


                    values:


                      - linux


                  - key: beta.kubernetes.io/arch


                    operator: In


                    values:


                      - arm


      hostNetwork: true


      tolerations:


      - operator: Exists


        effect: NoSchedule


      serviceAccountName: flannel


      initContainers:


      - name: install-cni


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-arm


        command:


        - cp


        args:


        - -f


        - /etc/kube-flannel/cni-conf.json


        - /etc/cni/net.d/10-flannel.conflist


        volumeMounts:


        - name: cni


          mountPath: /etc/cni/net.d


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      containers:


      - name: kube-flannel


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-arm


        command:


        - /opt/bin/flanneld


        args:


        - --ip-masq


        - --kube-subnet-mgr


        resources:


          requests:


            cpu: "100m"


            memory: "50Mi"


          limits:


            cpu: "100m"


            memory: "50Mi"


        securityContext:


          privileged: false


          capabilities:


             add: ["NET_ADMIN"]


        env:


        - name: POD_NAME


          valueFrom:


            fieldRef:


              fieldPath: metadata.name


        - name: POD_NAMESPACE


          valueFrom:


            fieldRef:


              fieldPath: metadata.namespace


        volumeMounts:


        - name: run


          mountPath: /run/flannel


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      volumes:


        - name: run


          hostPath:


            path: /run/flannel


        - name: cni


          hostPath:


            path: /etc/cni/net.d


        - name: flannel-cfg


          configMap:


            name: kube-flannel-cfg


---


apiVersion: apps/v1


kind: DaemonSet


metadata:


  name: kube-flannel-ds-ppc64le


  namespace: kube-system


  labels:


    tier: node


    app: flannel


spec:


  selector:


    matchLabels:


      app: flannel


  template:


    metadata:


      labels:


        tier: node


        app: flannel


    spec:


      affinity:


        nodeAffinity:


          requiredDuringSchedulingIgnoredDuringExecution:


            nodeSelectorTerms:


              - matchExpressions:


                  - key: beta.kubernetes.io/os


                    operator: In


                    values:


                      - linux


                  - key: beta.kubernetes.io/arch


                    operator: In


                    values:


                      - ppc64le


      hostNetwork: true


      tolerations:


      - operator: Exists


        effect: NoSchedule


      serviceAccountName: flannel


      initContainers:


      - name: install-cni


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-ppc64le


        command:


        - cp


        args:


        - -f


        - /etc/kube-flannel/cni-conf.json


        - /etc/cni/net.d/10-flannel.conflist


        volumeMounts:


        - name: cni


          mountPath: /etc/cni/net.d


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      containers:


      - name: kube-flannel


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-ppc64le


        command:


        - /opt/bin/flanneld


        args:


        - --ip-masq


        - --kube-subnet-mgr


        resources:


          requests:


            cpu: "100m"


            memory: "50Mi"


          limits:


            cpu: "100m"


            memory: "50Mi"


        securityContext:


          privileged: false


          capabilities:


             add: ["NET_ADMIN"]


        env:


        - name: POD_NAME


          valueFrom:


            fieldRef:


              fieldPath: metadata.name


        - name: POD_NAMESPACE


          valueFrom:


            fieldRef:


              fieldPath: metadata.namespace


        volumeMounts:


        - name: run


          mountPath: /run/flannel


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      volumes:


        - name: run


          hostPath:


            path: /run/flannel


        - name: cni


          hostPath:


            path: /etc/cni/net.d


        - name: flannel-cfg


          configMap:


            name: kube-flannel-cfg


---


apiVersion: apps/v1


kind: DaemonSet


metadata:


  name: kube-flannel-ds-s390x


  namespace: kube-system


  labels:


    tier: node


    app: flannel


spec:


  selector:


    matchLabels:


      app: flannel


  template:


    metadata:


      labels:


        tier: node


        app: flannel


    spec:


      affinity:


        nodeAffinity:


          requiredDuringSchedulingIgnoredDuringExecution:


            nodeSelectorTerms:


              - matchExpressions:


                  - key: beta.kubernetes.io/os


                    operator: In


                    values:


                      - linux


                  - key: beta.kubernetes.io/arch


                    operator: In


                    values:


                      - s390x


      hostNetwork: true


      tolerations:


      - operator: Exists


        effect: NoSchedule


      serviceAccountName: flannel


      initContainers:


      - name: install-cni


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-s390x


        command:


        - cp


        args:


        - -f


        - /etc/kube-flannel/cni-conf.json


        - /etc/cni/net.d/10-flannel.conflist


        volumeMounts:


        - name: cni


          mountPath: /etc/cni/net.d


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      containers:


      - name: kube-flannel


        image: quay-mirror.qiniu.com/coreos/flannel:v0.11.0-s390x


        command:


        - /opt/bin/flanneld


        args:


        - --ip-masq


        - --kube-subnet-mgr


        resources:


          requests:


            cpu: "100m"


            memory: "50Mi"


          limits:


            cpu: "100m"


            memory: "50Mi"


        securityContext:


          privileged: false


          capabilities:


             add: ["NET_ADMIN"]


        env:


        - name: POD_NAME


          valueFrom:


            fieldRef:


              fieldPath: metadata.name


        - name: POD_NAMESPACE


          valueFrom:


            fieldRef:


              fieldPath: metadata.namespace


        volumeMounts:


        - name: run


          mountPath: /run/flannel


        - name: flannel-cfg


          mountPath: /etc/kube-flannel/


      volumes:


        - name: run


          hostPath:


            path: /run/flannel


        - name: cni


          hostPath:


            path: /etc/cni/net.d


        - name: flannel-cfg


          configMap:


            name: kube-flannel-cfg