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kubernetes安装及集群搭建

2023-06-13 09:13:12 时间

k8s安装

kubernetes官网

安装环境

不支持centos8的系统

IP

服务

硬件要求

192.168.2.10(node1)

Docker(已安装)、kubernetes

内存4G,双核CPU

192.168.2.20(node2)

Docker(已安装)、kubernetes

内存4G,双核CPU

192.168.2.30(node3)

Docker(已安装)、kubernetes

内存4G,双核CPU

安装步骤

环境准备 为了修改文件传输文件的方便,将主机名更改为安装环境所述的node,并写入hosts文件

ssh设置

node1

[root@localhost ~]# vim /etc/hosts
192.168.2.10 node1
192.168.2.20 node2
192.168.2.30 node3

ssh免密

方便传输文件

node1

[root@localhost ~]# ssh-keygen
[root@localhost ~]# ssh-copy-id -i root@node2
[root@localhost ~]# ssh-copy-id -i root@node3

传输hosts文件

[root@localhost ~]# scp /etc/hosts root@node2:/etc
[root@localhost ~]# scp /etc/hosts root@node3:/etc

更改主机名

node1

[root@localhost ~]# hostname node1
[root@localhost ~]# bash
[root@node1 ~]#

node2

[root@localhost ~]# hostname node2
[root@localhost ~]# bash
[root@node2 ~]#

node3

[root@localhost ~]# hostname node3
[root@localhost ~]# bash
[root@node3 ~]#

关闭防火墙沙盒

node1/2/3

systemctl stop firewalld && systemctl disable firewalld
setenforce 0
vim /etc/selinux/config 
# 修改
SELINUX=disabled

kubernetes安装环境要求

官方文档

防火墙端口 如果不关闭防火墙,请放下以下端口 Master节点

Node节点

验证每个节点的mac地址和product_uuid是唯一的

kubernetes通过这两个值来确定集群中的节点

node1

[root@node1 ~]# cat /sys/class/dmi/id/product_uuid
19D84D56-03C0-B76A-96EA-37D54065C278

node2

[root@node2 ~]# cat /sys/class/dmi/id/product_uuid
D8304D56-8AB4-7444-D531-C67AF37581C7

node3

[root@node3 ~]# cat /sys/class/dmi/id/product_uuid
69E84D56-2D4B-3E4E-9DE8-4D7B44052C25

关闭swap分区

三台操作同样,这一步不要scp,因为fstab不一样

swapoff -a
vim /etc/fstab 
将分区类型为swap的一行注释掉
/dev/mapper/centos-swap swap

查看是否关闭

[root@node1 ~]# free -m
              total        used        free      shared  buff/cache   available
Mem:           2793        1024         206          14        1562        1334
Swap:             0           0           0

下载第三方依赖的库文件(会解决很多依赖关系)

node1/2/3

yum install epel-release -y

node1

[root@node1 ~]# vim /etc/sysctl.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
vm.swappiness = 0   # 当内存oom是不使用交换分区

如果发现那两条显示没有那个文件或目录,然后先导入两个模块(多敲几次)

modprobe  ip_vs_rr
modprobe br_netfilter

让参数生效

[root@node1 ~]# sysctl -p
net.ipv4.ip_forward = 1
vm.swappiness = 0
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1

传输过去

[root@node1 ~]# scp /etc/sysctl.conf root@node2:/etc
[root@node1 ~]# scp /etc/sysctl.conf root@node3:/etc

node2

[root@node2 ~]# modprobe  ip_vs_rr
[root@node2 ~]# modprobe br_netfilter
[root@node2 ~]# sysctl -p

node3

[root@node3 ~]# modprobe  ip_vs_rr
[root@node3 ~]# modprobe br_netfilter
[root@node3 ~]# sysctl -p

kubernetes安装 这里使用阿里云镜像站安装 kubernetes阿里云镜像站 node1

进入上面这个页面,使用centos的yum源

[root@node1 ~]# vim /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

将yum源传给每台主机

[root@node1 ~]# scp /etc/yum.repos.d/kubernetes.repo root@node2:/etc/yum.repos.d/
[root@node1 ~]# scp /etc/yum.repos.d/kubernetes.repo root@node3:/etc/yum.repos.d/

node1/2/3

yum install -y kubelet kubeadm kubectl
  • kubeadm:引导集群的命令。
  • kubelet:在群集中所有计算机上运行的组件,它执行诸如启动Pod和容器之类的操作。
  • kubectl:用于与您的集群通信的命令行工具。

三台启动服务

systemctl enable kubelet.service && systemctl start kubelet.service
systemctl start docker.service

安装kubernetes的tab快捷键

[root@node1 ~]# source <(kubectl completion bash)
[root@node1 ~]# source <(kubeadm completion bash)

查看版本

[root@node1 ~]# kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"18", GitVersion:"v1.18.3", GitCommit:"2e7996e3e2712684bc73f0dec0200d64eec7fe40", GitTreeState:"clean", BuildDate:"2020-05-20T12:49:29Z", GoVersion:"go1.13.9", Compiler:"gc", Platform:"linux/amd64"}

kubernetes创建集群

node1

执行这条后会等待一段时间,需要进行下载镜像

kubeadm init --apiserver-advertise-address 192.168.2.10 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.18.3 --pod-network-cidr=10.244.0.0/16
参数释义

–apiserver-advertise-address:通告侦听地址 –image-repository:指定镜像地址使用阿里云的,默认会使用谷歌镜像 –kubernetes-version:指定当前的kubernetes的版本 –pod-network-cidr=10.244.0.0/16:flannel网络的固定地址范围

成功则会返回如下信息:
# 如果使用普通账号操作,执行以下三条 

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

# 部署集群网络
  https://kubernetes.io/docs/concepts/cluster-administration/addons/

# 其他kubernetes主机通过以下命令加入kubernetes集群

kubeadm join 192.168.2.10:6443 --token 1dnjl6.51yjfkjm2ys5p6gx \
    --discovery-token-ca-cert-hash sha256:e5b6bfc12b3b0e7101ffb6433ae0c0be7a7a24aaf322112b59e1b577c0f9256d 

如果是root用户先执行以下命令

export KUBECONFIG=/etc/kubernetes/admin.conf
加入命令创建有效期24小时,允许管理我们的令牌,如果丢了就会出现错误

查看计算机当中的令牌

[root@node1 ~]# kubeadm token list
TOKEN                     TTL         EXPIRES                     USAGES                   DESCRIPTION                                                EXTRA GROUPS
1dnjl6.51yjfkjm2ys5p6gx   17h         2020-06-11T09:43:35+08:00   authentication,signing   The default bootstrap token generated by 'kubeadm init'.   system:bootstrappers:kubeadm:default-node-token

部署集群网络

浏览器打开地址https://kubernetes.io/docs/concepts/cluster-administration/addons/ 找到下图位置,点击flannel

进入Documentation目录下
找到kube-flannel.yml文件

将里面的内容进行复制到虚拟机的kube-flannel.yml文件

[root@node1 ~]# vi 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: quay.io/coreos/flannel:v0.12.0-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.io/coreos/flannel:v0.12.0-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: 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: quay.io/coreos/flannel:v0.12.0-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.io/coreos/flannel:v0.12.0-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: 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: quay.io/coreos/flannel:v0.12.0-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.io/coreos/flannel:v0.12.0-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: 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: quay.io/coreos/flannel:v0.12.0-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.io/coreos/flannel:v0.12.0-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: 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: quay.io/coreos/flannel:v0.12.0-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.io/coreos/flannel:v0.12.0-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
找到该位置,此镜像需要使用docker下载

所有主机尽量都pull一下也是可以的

[root@node1 ~]# docker pull quay.io/coreos/flannel:v0.12.0-amd64

部署集群网络

[root@node1 ~]# kubectl apply -f kube-flannel.yml

node2/3加入集群

kubeadm join 192.168.2.10:6443 --token 1dnjl6.51yjfkjm2ys5p6gx \
    --discovery-token-ca-cert-hash sha256:e5b6bfc12b3b0e7101ffb6433ae0c0be7a7a24aaf322112b59e1b577c0f9256d 

完成后输出一下信息

This node has joined the cluster:
* Certificate signing request was sent to apiserver and a response was received.
* The Kubelet was informed of the new secure connection details.
 
Run 'kubectl get nodes' on the control-plane to see this node join the cluster.

node1

在node1运行kubectl get nodes查看集群节点,状态的为Notready的是还没有准备好,多等一会,再去查看

[root@node1 ~]# kubectl get nodes
NAME      STATUS   ROLES    AGE     VERSION
server1   Ready    master   6h35m   v1.18.3
server2   Ready    <none>   6h27m   v1.18.3
server3   Ready    <none>   6h27m   v1.18.3

如果发现节点为Notready,时间长也不行,将默认的网络插件cni去掉,集群中全部修改

vim /var/lib/kubelet/kubeadm-flags.env
# 删除--network-plugin=cni

重新启动

systemctl daemon-reload
systemctl restart kubelet

此时的kubelet才启动成功。 重新查看集群状态

执行kubectl get pod --all-namespaces,查看所有命名空间的pod,如果有状态为PodInitializing,就多等一会,网络原因,pod插件没有下载好,多等等就好了,全部这台为running即可

[root@node1 ~]# kubectl get pod --all-namespaces
NAMESPACE     NAME                                READY   STATUS    RESTARTS   AGE
kube-system   coredns-7ff77c879f-dvh7g            1/1     Running   0          6h38m
kube-system   coredns-7ff77c879f-gk9zd            1/1     Running   0          6h38m
kube-system   etcd-server1                        1/1     Running   0          6h38m
kube-system   kube-apiserver-server1              1/1     Running   0          6h38m
kube-system   kube-controller-manager-server1     1/1     Running   0          6h38m
kube-system   kube-flannel-ds-amd64-tdcnh         1/1     Running   0          6h30m
kube-system   kube-flannel-ds-amd64-thsxp         1/1     Running   2          6h30m
kube-system   kube-flannel-ds-amd64-twqjf         1/1     Running   2          6h30m
kube-system   kube-proxy-4drcp                    1/1     Running   0          6h30m
kube-system   kube-proxy-fts9q                    1/1     Running   0          6h38m
kube-system   kube-proxy-jnb7c                    1/1     Running   0          6h30m
kube-system   kube-scheduler-server1              1/1     Running   0          6h38m

集群搭建成功