Kubeadm初始化Kubernetes集群

1.环境

• matser,etcd: 192.168.33.30
• node1: 192.168.33.40
• node2: 192.168.33.50

前提

• 1、基于主机名通信：/etc/hosts
• 2、时间同步
• 3、关闭firewall和iptables.service
• 4、OS:CentOS 7.6.1810

安装配置步骤：

• 1、etcd cluster，仅master节点；
• 2、flannel，集群的所有节点；
• 3、配置K8s的master：仅master节点；
  • kubenetes-master
  • 启动的服务：kube-apiserver，kube-scheduler，kube-controller-manager
• 4、配置k8s的各node节点：Kubernetes-node
  • 先设定启动docker服务；启动k8s的服务：kube-proxy，kubelet

kubeadm

• 1、master，node：安装kubelet，kubeamd，docker
• 2、master：kubeadm init
• 3、nodes：kubeadm join

master部署

1. 安装dokcer-ce

2. 配置阿里云的Kubernetes源

   [[email protected] yum.repos.d]# vim kubernetes.repo
   [kubernetes]
    name=kubernetes Repo
    baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
    gpgcheck=0
    gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
    enabled=1
   
   

3. 把Kubernetes源分别复制到node1和node2

   [[email protected] yum.repos.d]# scp kubernetes.repo node1:/etc/yum.repos.d/
   [[email protected] yum.repos.d]# scp kubernetes.repo node2:/etc/yum.repos.d/
   

4. yum安装kubeadm、kubelet、kubectl

   [[email protected] yum.repos.d]# yum install kubeadm kubelet kubectl
   

   注：出现d87e7e3e61cc561f18376d2caa53207ba96b932ca2011be9e8e370bdc281d859-kubeadm-1.15.3-0.x86_64.rpm 的公钥尚未安装解决办法

   [[email protected] yum.repos.d]# vim kubernetes.repo
   gpgcheck=0
   [[email protected] yum.repos.d]# cd
   [[email protected] ~]# wget https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
   [[email protected] ~]# rpm --import yum-key.gpg
   [[email protected] ~]# yum install kubeadm kubelet kubectl
   

5. 设置docker的环境变量

   [[email protected] ~]# vim /usr/lib/systemd/system/docker.service
   [Service]
   ExecStartPost=/sbin/iptables -I FORWARD -s 0.0.0.0/0 -j ACCEPT
   [[email protected] ~]# systemctl daemon-reload 
   [[email protected] ~]# systemctl restart docker.service 
   [[email protected] ~]# docker info
   

6. 查看kubelet的目录

[[email protected] ~]# rpm -ql kubelet 
/etc/kubernetes/manifests
/etc/sysconfig/kubelet
/usr/bin/kubelet
/usr/lib/systemd/system/kubelet.service

7. 设置docker、kubelet开机自启

   [[email protected] ~]# systemctl enable docker.service
   [[email protected] ~]# systemctl enable kubelet.service
   

8. kubeamd初始化

[[email protected] ~]# docker pull mirrorgooglecontainers/kube-apiserver:v1.15.0
[[email protected] ~]# docker pull mirrorgooglecontainers/kube-controller-manager:v1.15.0
[[email protected] ~]# docker pull mirrorgooglecontainers/kube-scheduler:v1.15.0
[[email protected] ~]# docker pull mirrorgooglecontainers/kube-proxy:v1.15.0
[[email protected] ~]# docker pull mirrorgooglecontainers/pause:3.1
[[email protected] ~]# docker pull mirrorgooglecontainers/etcd:3.3.10
[[email protected] ~]# docker pull coredns/coredns:1.3.1
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/kube-apiserver:v1.15.0 k8s.gcr.io/kube-apiserver:v1.15.0
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/kube-controller-manager:v1.15.0 k8s.gcr.io/kube-controller-manager:v1.15.0
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/kube-scheduler:v1.15.0 k8s.gcr.io/kube-scheduler:v1.15.0
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/kube-proxy:v1.15.0 k8s.gcr.io/kube-proxy:v1.15.0
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/pause:3.1 k8s.gcr.io/pause:3.1
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/etcd:3.3.10 k8s.gcr.io/etcd:3.3.10
[[email protected] ~]# docker tag docker.io/coredns/coredns:1.3.1 k8s.gcr.io/coredns:1.3.1
[[email protected] ~]# vim /etc/sysconfig/kubelet
KUBELET_EXTRA_ARGS="--fail-swap-on=false"
[[email protected] ~]# kubeadm init --kubernetes-version=v1.11.1 --pod-network-cidr=10.244.0.0/16 --service-cidr=10.96.0.0/12 --ignore-preflight-errors=Swap

9. 把yum-key.gpg分别复制给node1和node2

[[email protected] ~]# scp yum-key.gpg node1:/root
[[email protected] ~]# scp yum-key.gpg node2:/root

10. 创建kebe配置文件，认证证书

[[email protected] ~]# mkdir -p $HOME/.kube
[[email protected] ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config

11.手动部署flannel,且要指定namespace

[[email protected] ~]# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
[[email protected] ~]# kubectl get nodes
NAME     STATUS   ROLES    AGE   VERSION
master   Ready    master   44h   v1.15.3
[[email protected] ~]# kubectl get pods -n kube-system
NAME                             READY   STATUS    RESTARTS   AGE
coredns-5c98db65d4-55zlf         1/1     Running   0          44h
coredns-5c98db65d4-qsb7s         1/1     Running   0          44h
etcd-master                      1/1     Running   0          44h
kube-apiserver-master            1/1     Running   0          44h
kube-controller-manager-master   1/1     Running   1          44h
kube-flannel-ds-amd64-xpflj      1/1     Running   0          5m58s
kube-proxy-6x6sx                 1/1     Running   0          44h
kube-scheduler-master            1/1     Running   1          44h

node1部署

1.yum安装docker、kubeadm、kubelet

[[email protected] ~]# rpm --import yum-key.gpg 
[[email protected] ~]# yum install kubelet kubeadm

2.在master中把相关的配置文件复制到node1和node2

[[email protected] ~]# scp /usr/lib/systemd/system/docker.service node1:/usr/lib/systemd/system/docker.service
[[email protected] ~]# scp /usr/lib/systemd/system/docker.service node2:/usr/lib/systemd/system/docker.service
[[email protected] ~]# scp /etc/sysconfig/kubelet node1:/etc/sysconfig/
[[email protected] ~]# scp /etc/sysconfig/kubelet node2:/etc/sysconfig/

3.重启docker，并把kubelet加入开机自启

[[email protected] ~]# systemctl daemon-reload
[[email protected] ~]# systemctl restart docker.service
[[email protected] ~]# systemctl enable kubelet.service

4.在node1上下载组件镜像

[[email protected] ~]# docker pull mirrorgooglecontainers/kube-proxy:v1.15.0
[[email protected] ~]# docker pull mirrorgooglecontainers/pause:3.1
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/kube-proxy:v1.15.0 k8s.gcr.io/kube-proxy-amd64:v1.15.0
[[email protected] ~]# docker tag docker.io/mirrorgooglecontainers/pause:3.1  k8s.gcr.io/pause:3.1
[[email protected] ~]# docker rmi mirrorgooglecontainers/kube-proxy:v1.15.0
[[email protected] ~]# docker rmi mirrorgooglecontainers/pause:3.1

5.把node1节点加入集群

[[email protected] ~]# kubeadm token create --ttl 0 --print-join-command
kubeadm join 192.168.33.30:6443 --token 9n0jkf.xu5rdhgz8db2aurk     --discovery-token-ca-cert-hash sha256:75f6da989069173c6092c3a127912bee2cc30f16eb3b2c0d442f0081bc5751dc
[[email protected] ~]# kubeadm join 192.168.33.30:6443 --token q8mkp7.61eo6ayjhanap8uv --discovery-token-ca-cert-hash sha256:75f6da989069173c6092c3a127912bee2cc30f16eb3b2c0d442f0081bc5751dc --ignore-preflight-errors=Swap

6.在master上查看node1是否加入

[[email protected] ~]# kubectl get pods -n kube-system -o wide
[[email protected] ~]# kubectl get nodes
NAME     STATUS   ROLES    AGE   VERSION
master   Ready    master   47h   v1.15.3
node1    Ready    <none>   99s   v1.15.3

node2加入集群跟node1一样