简述

为什么要学习k8s https://www.jianshu.com/p/dfbf8167eb0d

有没有简单的安装方式 https://www.jianshu.com/p/0278d851c7d4

大家都清楚，k8s好用，但是安装却异常困难

也正是因为如此，大大的提升了我们学习的门槛

本次分享，是经过无数次采坑得到的经验，希望对大家有些帮助

环境配置

本人使用的VMware和阿里云centos7镜像搭建的虚拟机

这里VMware不多做介绍了

阿里云CentOS镜像地址 https://developer.aliyun.com/mirror/centos?spm=a2c6h.13651102.0.0.3e221b11FiHUF6

#####注意：master机器需要4核8G配置 既 cpu>=4c MEM>=8g；node机器需要2核4G配置 既 cpu>=2c MEM>=4g

##开始安装
1.设置主机名（每台都操作）

hostnamectl set-hostname master

2.配置host

cat <<EOF >>/etc/hosts
[master节点IP] master
[node节点IP] node01
[node节点IP] node02
EOF

3.关闭每台机器防火墙,postfix，selinux，swap。

systemctl disable firewalld && systemctl stop firewalld
systemctl disable postfix && systemctl stop postfix
setenforce 0 && sed -i "s/^SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config
swapoff -a && sed -i 's/.*swap.*/#&/' /etc/fstab

4.将桥接的IPv4流量传递到iptables的链【有一些ipv4的流量不能走iptables链【linux内核的一个过滤器，每个流量都会经过他，然后再匹配是否可进入当前应用进程去处理】，导致流量丢失】：配置k8s.conf文件（#k8s.conf文件原来不存在，需要自己创建的）

cat > /etc/sysctl.d/k8s.conf <<EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system

5.配置CentOS国内阿里云源,安装所需软件包。其他节点同样操作一遍。

cd /etc/yum.repos.d/
mkdir backup
mv ./*.repo backup
curl -O http://mirrors.aliyun.com/repo/Centos-7.repo
curl -O https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
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=0
EOF
yum clean all && yum makecache
yum -y install docker-ce docker-ce-cli containerd.io kubelet kubeadm kubectl
systemctl enable docker --now
cat > /etc/docker/daemon.json <<EOF
{
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "storage-driver": "overlay2",
  "storage-opts": [
    "overlay2.override_kernel_check=true"
  ]
}
EOF
mkdir -p /etc/systemd/system/docker.service.d
systemctl daemon-reload && systemctl restart docker
systemctl enable kubelet --now

至此我们已经安装并启动了 docker-ce、docker-ce-cli、containerd.io、kubelet、kubeadm、kubectl

6.在master节点初始化集群

kubeadm init --kubernetes-version=1.18.5 --apiserver-advertise-address=[master节点IP]  --service-cidr=10.1.0.0/16 --pod-network-cidr=10.244.0.0/16 --image-repository registry.cn-shanghai.aliyuncs.com/k8sgcrio_containers

–kubernetes-version 为控制平面选择一个特定的 Kubernetes 版本。
–apiserver-advertise-address API 服务器所公布的其正在监听的 IP 地址。如果未设置，则使用默认网络接口。
–service-cidr 为服务的虚拟 IP 地址另外指定 IP 地址段
–pod-network-cidr 指明 pod 网络可以使用的 IP 地址段。如果设置了这个参数，控制面板将会为每一个节点自动分配 CIDRs。
–image-repository 选择用于拉取控制面板镜像的容器仓库 默认 k8s.gcr.io

更多初始化参数请参考 https://kubernetes.io/zh/docs/reference/setup-tools/kubeadm/kubeadm-init/

这里我并没有用官方的镜像，相信安装过k8s的小伙伴都知道，大多会出现因为镜像拉取不到而安装失败，所以大家会去选择，阿里开源的镜像，但是阿里云镜像仓库并没有更新到1.18.5版本，所以我自己创建了一个公开的镜像仓库，并把需要用的镜像组件放入仓库，如果你经常安装的话，建议你也用同样的方式把镜像放到自己的镜像仓库，因为自己的才是最保险的嘛，哈哈哈
我这里的镜像也是从别人的仓库获得

这里就不对阿里镜像仓库做过多介绍了，感兴趣的话，登录自己的阿里云，你会找打答案

初始化成功你会看到如下结果
第一个框提示你配置基础的kubectl 配置文件
第二个框提示你其他节点加入的命令，token 及 --discovery-token-ca-cert-hash 都在命令里面
7.kubectl 配置文件：

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

8.部署网路文件,我们首选(flannel)：
大家可以尝试访问下这个链接：https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
上面链接中使用的是官方的镜像，正如我上面说的，可能出现超时，拉取不到等问题
所以我这里也做了同样的公共镜像仓库

如果上面的失败了，可以直接用我的
kube-flannel.yml

---
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: kubernetes.io/os
                    operator: In
                    values:
                      - linux
                  - key: kubernetes.io/arch
                    operator: In
                    values:
                      - amd64
      hostNetwork: true
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni
        image: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: kubernetes.io/os
                    operator: In
                    values:
                      - linux
                  - key: kubernetes.io/arch
                    operator: In
                    values:
                      - arm64
      hostNetwork: true
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni
        image: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: kubernetes.io/os
                    operator: In
                    values:
                      - linux
                  - key: kubernetes.io/arch
                    operator: In
                    values:
                      - arm
      hostNetwork: true
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni
        image: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: kubernetes.io/os
                    operator: In
                    values:
                      - linux
                  - key: kubernetes.io/arch
                    operator: In
                    values:
                      - ppc64le
      hostNetwork: true
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni
        image: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: kubernetes.io/os
                    operator: In
                    values:
                      - linux
                  - key: kubernetes.io/arch
                    operator: In
                    values:
                      - s390x
      hostNetwork: true
      tolerations:
      - operator: Exists
        effect: NoSchedule
      serviceAccountName: flannel
      initContainers:
      - name: install-cni
        image: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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: registry.cn-zhangjiakou.aliyuncs.com/test-lab/coreos-flannel: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

我们来看下节点的状态

kubectl get nodes

部署网络文件：

kubectl apply -f kube-flannel.yml

再看下节点状态

OK!,我们的master节点部署成功
其他节点加入

kubeadm join 192.168.48.134:6443 --token sbymfx.vrmopbhinoofzgdh \
    --discovery-token-ca-cert-hash sha256:a82595638ab5d8ff1c6ce82a5e65f588caae01758035dab5131216d07bd1d0bd 

至此k8s的安装就完成啦，
有什么问题可以在下面提问
附上文献：https://blog.csdn.net/ZouChengli/article/details/107241595