这篇文章给大家分享的是Kubeadm部署Kubernetes集群的步骤，相信大部分人都还不知道怎么部署，为了让大家学会，给大家总结了以下内容，话不多说，一起往下看吧。
一、环境准备
操作系统 | IP地址 | 主机名 | 组件 |
CentOS7.5 | 192.168.200.111 | docker-server1 | kubeadm、kubelet、kubectl、docker-ce |
CentOS7.5 | 192.168.200.112 | docker-server2 | kubeadm、kubelet、kubectl、docker-ce |
CentOS7.5 | 192.168.200.113 | docker-server3 | kubeadm、kubelet、kubectl、docker-ce |
注意：所有主机配置推荐CPU：2C+ Memory：2G+
1.1、主机初始化配置
所有主机配置禁用防火墙和selinux，配置主机名
[root@localhost ~]# iptables -F
[root@localhost ~]# setenforce 0
[root@localhost ~]# systemctl stop firewalld
不同主机名称不同（分别为docker-server2、docker-server3）
[root@localhost ~]# hostname docker-server1
[root@localhost ~]# bash
[root@docker-server1 ~]# vim /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.200.111 docker-server1
192.168.200.112 docker-server1
192.168.200.113 docker-server1
[root@docker-server1 ~]# scp /etc/hosts 192.168.200.112:/etc/
[root@docker-server1 ~]# scp /etc/hosts 192.168.200.113:/etc/
禁用swap虚拟内存
[root@docker-server1 ~]# vim /etc/fstab
#/dev/mapper/centos-swap swap swap defaults 0 0 #禁用swap自动挂载
[root@docker-server1 ~]# swapoff /dev/mapper/centos-swap
[root@docker-server1 ~]# free -h
total used free shared buff/cache available
Mem: 1.9G 749M 101M 10M 1.1G 906M
Swap: 0B 0B 0B
1.2、部署docker环境
安装docker-ce（所有主机配置）
[root@docker-server1 ~]# wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
[root@docker-server1 ~]# yum -y install yum-utils device-mapper-persistent-data lvm2
[root@docker-server1 ~]# yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
[root@docker-server1 ~]# ls /etc/yum.repos.d/
backup CentOS-Base.repo CentOS-Media.repo docker-ce.repo
[root@docker-server1 ~]# yum -y install docker-ce
[root@docker-server1 ~]# systemctl start docker && systemctl enable docker
阿里云镜像加速器（所有主机配置）
[root@docker-server1 ~]# cat << END > /etc/docker/daemon.json
{
"registry-mirrors":[ "https://nyakyfun.mirror.aliyuncs.com" ]
}
END
[root@docker-server1 ~]# systemctl daemon-reload
[root@docker-server1 ~]# systemctl restart docker
[root@docker-server1 ~]# docker version
Client: Docker Engine - Community
Version: 19.03.5
API version: 1.40
Go version: go1.12.12
Git commit: 633a0ea
Built: Wed Nov 13 07:25:41 2019
OS/Arch: linux/amd64
Experimental: false
Server: Docker Engine - Community
Engine:
Version: 19.03.5
API version: 1.40 (minimum version 1.12)
Go version: go1.12.12
Git commit: 633a0ea
Built: Wed Nov 13 07:24:18 2019
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: 1.2.10
GitCommit: b34a5c8af56e510852c35414db4c1f4fa6172339
runc:
Version: 1.0.0-rc8+dev
GitCommit: 3e425f80a8c931f88e6d94a8c831b9d5aa481657
docker-init:
Version: 0.18.0
GitCommit: fec3683
1.3、相关组件版本说明
组件 | 版本 | 说明 |
kubernetes | 1.17.3 | 主程序 |
docker | 19.03.5 | 容器 |
flannel | 0.11.0 | 网络插件 |
etcd | 3.3.15 | 数据库 |
coredns | 1.6.2 | dns组件 |
kubernetes-dashboard | 2.0.0-beta5 | web界面 |
二、部署kubernetes集群
2.1、组件介绍
三个节点都需要安装下面三个组件
l kubeadm：安装工具，使所有的组件都会以容器的方式运行
l kubectl：客户端连接K8S API工具
l kubelet：运行在node节点，用来启动容器的工具
2.2、配置阿里云yum源
所有主机配置yum源
推荐使用阿里云的yum源安装：
[root@docker-server1 ~]# 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
[root@docker-server1 ~]# ls /etc/yum.repos.d/
backup CentOS-Base.repo CentOS-Media.repo docker-ce.repo kubernetes.repo
K8S目前最新版本是:1.17.3
[root@docker-server1 ~]# yum -y info kubeadm
已加载插件：fastestmirror, langpacks
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
kubernetes/signature | 454 B 00:00:00
从 https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg 检索密钥
导入 GPG key 0xA7317B0F:
用户ID : "Google Cloud Packages Automatic Signing Key <gc-team@google.com>"
指纹 : d0bc 747f d8ca f711 7500 d6fa 3746 c208 a731 7b0f
来自 : https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
从 https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg 检索密钥
kubernetes/signature | 1.4 kB 00:00:01 !!!
kubernetes/primary | 64 kB 00:00:00
kubernetes 469/469
可安装的软件包
名称 ：kubeadm
架构 ：x86_64
版本 ：1.17.3
发布 ：0
大小 ：8.7 M
源 ：kubernetes
简介 ： Command-line utility for administering a Kubernetes cluster.
网址 ：https://kubernetes.io
协议 ： ASL 2.0
描述 ： Command-line utility for administering a Kubernetes cluster.
2.3、安装kubelet kubeadm kubectl
所有主机配置
[root@docker-server1 ~]# yum install -y kubelet kubeadm kubectl
[root@docker-server1 ~]# rpm -qa | grep kube*
kubeadm-1.17.3-0.x86_64
kubelet-1.17.3-0.x86_64
kubernetes-cni-0.7.5-0.x86_64
kubectl-1.17.3-0.x86_64
[root@docker-server1 ~]# systemctl enable kubelet && systemctl start kubelet
2.4、加载内核模块
所有主机配置
[root@docker-server1 ~]# cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_nonlocal_bind = 1
net.ipv4.ip_forward = 1
vm.swappiness=0
EOF
[root@docker-server1 ~]# sysctl –system
[root@docker-server1 ~]# vim /etc/sysctl.conf
net.ipv4.ip_forward = 1
[root@docker-server1 ~]# sysctl -p
[root@docker-server1 ~]# cat > /etc/sysconfig/modules/ipvs.modules <<EOF
#!/bin/bash
modprobe -- br_netfilter
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF
[root@docker-server1 ~]# chmod 755 /etc/sysconfig/modules/ipvs.modules
[root@docker-server1 ~]# bash /etc/sysconfig/modules/ipvs.modules
[root@docker-server1 ~]# lsmod | grep -E "ip_vs|nf_conntrack_ipv4"
ip_vs_sh 12688 0
ip_vs_wrr 12697 0
ip_vs_rr 12600 0
ip_vs 141432 6 ip_vs_rr,ip_vs_sh,ip_vs_wrr
nf_conntrack_ipv4 15053 2
nf_defrag_ipv4 12729 1 nf_conntrack_ipv4
nf_conntrack 133053 7 ip_vs,nf_nat,nf_nat_ipv4,xt_conntrack,nf_nat_masquerade_ipv4,nf_conntrack_netlink,nf_conntr
ack_ipv4libcrc32c 12644 4 xfs,ip_vs,nf_nat,nf_conntrack
2.5、配置kubeadm-config.yaml
kubeadm-config.yaml组成部署说明：
l InitConfiguration：用于定义一些初始化配置，如初始化使用的token以及apiserver地址等;
l ClusterConfiguration：用于定义apiserver、etcd、network、scheduler、controller-manager等master组件相关配置项
l KubeletConfiguration：用于定义kubelet组件相关的配置项
l KubeProxyConfiguration：用于定义kube-proxy组件相关的配置项
在master节点安装，master 定于为192.168.200.111，通过如下指令创建默认的kubeadm-config.yaml文件：
[root@docker-server1 ~]# kubeadm config print init-defaults > kubeadm-config.yaml
W0212 21:18:11.685591 2403 validation.go:28] Cannot validate kube-proxy config - no validator is available
W0212 21:18:11.685648 2403 validation.go:28] Cannot validate kubelet config - no validator is available
kubeadm-config.yaml配置
[root@docker-server1 ~]# vim kubeadm-config.yaml
apiVersion: kubeadm.k8s.io/v1beta2
bootstrapTokens:
- groups:
- system:bootstrappers:kubeadm:default-node-token
token: abcdef.0123456789abcdef
ttl: 24h0m0s
usages:
- signing
- authentication
kind: InitConfiguration
localAPIEndpoint:
advertiseAddress: 192.168.200.111 #master节点的IP
bindPort: 6443
nodeRegistration:
criSocket: /var/run/dockershim.sock
name: 192.168.200.111 #修改为IP地址，如果使用域名，必须保证解析正常
taints:
- effect: NoSchedule
key: node-role.kubernetes.io/master
---
apiServer:
timeoutForControlPlane: 4m0s
apiVersion: kubeadm.k8s.io/v1beta2
certificatesDir: /etc/kubernetes/pki
clusterName: kubernetes
controllerManager: {}
dns:
type: CoreDNS
etcd:
local:
dataDir: /var/lib/etcd #把etcd容器的目录挂载到本地的/var/lib/etcd目录下，防止数据丢失
imageRepository: registry.cn-hangzhou.aliyuncs.com/google_containers #镜像仓库地址，可以修改为gcr.azk8s.cn/google_containers
kind: ClusterConfiguration
kubernetesVersion: v1.17.3 #Kubernetes软件版本
networking:
dnsDomain: cluster.local
serviceSubnet: 10.96.0.0/12
podSubnet: 10.244.0.0/16 #添加这个内容
scheduler: {}
2.6、安装master节点
可以预先下载镜像
[root@docker-server1 ~]# kubeadm config images pull --config kubeadm-config.yaml
安装matser节点
[root@docker-server1 ~]# kubeadm init --config kubeadm-config.yaml
W0214 15:07:53.469593 65073 validation.go:28] Cannot validate kube-proxy config - no validator is available
W0214 15:07:53.469677 65073 validation.go:28] Cannot validate kubelet config - no validator is available
[init] Using Kubernetes version: v1.17.3
[preflight] Running pre-flight checks
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd
". Please follow the guide at https://kubernetes.io/docs/setup/cri/[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] Starting the kubelet
[certs] Using certificateDir folder "/etc/kubernetes/pki"
[certs] Generating "ca" certificate and key
[certs] Generating "apiserver" certificate and key
[certs] apiserver serving cert is signed for DNS names [192.168.200.111 kubernetes kubernetes.default kubernetes.default.sv
c kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.200.111][certs] Generating "apiserver-kubelet-client" certificate and key
[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 [192.168.200.111 localhost] and IPs [192.168.200.111 127.0.0.1 ::1
][certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [192.168.200.111 localhost] and IPs [192.168.200.111 127.0.0.1 ::1]
[certs] Generating "etcd/healthcheck-client" certificate and key
[certs] Generating "apiserver-etcd-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"
W0214 15:12:35.410900 65073 manifests.go:214] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,R
BAC"[control-plane] Creating static Pod manifest for "kube-scheduler"
W0214 15:12:35.413190 65073 manifests.go:214] the default kube-apiserver authorization-mode is "Node,RBAC"; using "Node,R
BAC"[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/ma
nifests". This can take up to 4m0s[apiclient] All control plane components are healthy after 34.504759 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.17" in namespace kube-system with the configuration for the kubelets in th
e cluster[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node 192.168.200.111 as control-plane by adding the label "node-role.kubernetes.io/master=
''"[mark-control-plane] Marking the node 192.168.200.111 as control-plane by adding the taints [node-role.kubernetes.io/master
:NoSchedule][bootstrap-token] Using token: abcdef.0123456789abcdef
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term cer
tificate credentials[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstra
p Token[bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
[bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key
[addons] Applied essential addon: CoreDNS
[addons] Applied essential addon: kube-proxy
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
#安装完成，在master上操作
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/
Then you can join any number of worker nodes by running the following on each as root:
#用于添加node节点
kubeadm join 192.168.200.111:6443 --token abcdef.0123456789abcdef \
--discovery-token-ca-cert-hash sha256:c2d6067d5c3b12118275958dee222226d09a89fc5fb559687dc989d2508d5a50
kubeadm init 主要执行了以下操作：
[init]：指定版本进行初始化操作
[preflight] ：初始化前的检查和下载所需要的Docker 镜像文件
[kubelet-start] ：生成kubelet 的配置文件”/var/lib/kubelet/config.yaml”，没有这个文件kubelet无法启动，所以初始化之前的kubelet 实际上启动失败。
[certificates]：生成Kubernetes 使用的证书，存放在/etc/kubernetes/pki 目录中。
[kubeconfig] ：生成 Kubeconfig 文件，存放在/etc/kubernetes 目录中，组件之间通信需要使用对应文件。
[control-plane]：使用/etc/kubernetes/manifest 目录下的YAML 文件，安装 Master 组件。
[etcd]：使用/etc/kubernetes/manifest/etcd.yaml 安装Etcd 服务。
[wait-control-plane]：等待control-plan 部署的Master 组件启动。
[apiclient]：检查Master 组件服务状态。
[uploadconfig]：更新配置
[kubelet]：使用configMap 配置kubelet。
[patchnode]：更新CNI 信息到Node 上，通过注释的方式记录。
[mark-control-plane]：为当前节点打标签，打了角色Master，和不可调度标签，这样默认就不会使用Master 节点来运行Pod。
[bootstrap-token]：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
[addons]：安装附加组件CoreDNS 和kube-proxy
2.7、查看容器
[root@docker-server1 ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS
PORTS NAMES88167513e26b 7d54289267dc "/usr/local/bin/kube…" 6 minutes ago Up 6
minutes k8s_kube-proxy_kube-proxy-trrsg_kube-system_1d8ad663-c8d8-4429-9bfa-62c0644d048b_004ef064f9de7 registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 6 minutes ago Up 6 m
inutes k8s_POD_kube-proxy-trrsg_kube-system_1d8ad663-c8d8-4429-9bfa-62c0644d048b_0116a097c0f34 5eb3b7486872 "kube-controller-man…" 6 minutes ago Up 6
minutes k8s_kube-controller-manager_kube-controller-manager-192.168.200.111_kube-system_655c81bbe85f53920741e98506a879a4_0aa9676158688 303ce5db0e90 "etcd --advertise-cl…" 6 minutes ago Up 6
minutes k8s_etcd_etcd-192.168.200.111_kube-system_263a5d6fc4cb43d1291a4e7fc493a149_02f5d3ee4c848 78c190f736b1 "kube-scheduler --au…" 6 minutes ago Up 6
minutes k8s_kube-scheduler_kube-scheduler-192.168.200.111_kube-system_75516e998e1ab97384d969d8ccd139db_0f5d54e1fe069 0cae8d5cc64c "kube-apiserver --ad…" 6 minutes ago Up 6
minutes k8s_kube-apiserver_kube-apiserver-192.168.200.111_kube-system_c4b84d01dcb983c440c0474273fb535c_04c4a714c82fe registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 6 minutes ago Up 6 m
inutes k8s_POD_kube-controller-manager-192.168.200.111_kube-system_655c81bbe85f53920741e98506a879a4_06d5de46ad990 registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 6 minutes ago Up 6 m
inutes k8s_POD_kube-apiserver-192.168.200.111_kube-system_c4b84d01dcb983c440c0474273fb535c_0a1436b78e49e registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 6 minutes ago Up 6 m
inutes k8s_POD_etcd-192.168.200.111_kube-system_263a5d6fc4cb43d1291a4e7fc493a149_03a6901465499 registry.cn-hangzhou.aliyuncs.com/google_containers/pause:3.1 "/pause" 6 minutes ago Up 6 m
inutes k8s_POD_kube-scheduler-192.168.200.111_kube-system_75516e998e1ab97384d969d8ccd139db_0
根据提示操作
kubectl 默认会在执行的用户家目录下面的.kube 目录下寻找config 文件。这里是将在初始化时[kubeconfig]步骤生成的admin.conf 拷贝到.kube/config
[root@docker-server1 ~]# mkdir -p $HOME/.kube
[root@docker-server1 ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@docker-server1 ~]# chown $(id -u):$(id -g) $HOME/.kube/config
在该配置文件中，记录了API Server 的访问地址，所以后面直接执行kubectl 命令就可以正常连接到API Server 中
查看node节点和组件
[root@docker-server1 ~]# kubectl get cs
NAME STATUS MESSAGE ERROR
controller-manager Healthy ok
scheduler Healthy ok
etcd-0 Healthy {"health":"true"}
[root@docker-server1 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
192.168.200.111 NotReady master 7m52s v1.17.3
[root@docker-server1 ~]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-7f9c544f75-wx6q9 0/1 Pending 0 52m
coredns-7f9c544f75-x5nff 0/1 Pending 0 52m
etcd-192.168.200.111 1/1 Running 0 52m
kube-apiserver-192.168.200.111 1/1 Running 0 52m
kube-controller-manager-192.168.200.111 1/1 Running 0 52m
kube-proxy-pfz6z 1/1 Running 0 52m
kube-scheduler-192.168.200.111 1/1 Running 0 52m
发现两个问题：
1) core节点为pending：是因为需要node节点，但是还没有安装node节点，所以是pending
2) status是notready状态：是因为还没有安装网络插件
2.8、安装flannel
Master 节点NotReady 的原因就是因为没有使用任何的网络插件，此时Node 和Master的连接还不正常。目前最流行的Kubernetes 网络插件有Flannel、Calico、Canal、Weave 这里选择使用flannel。
在master 节点上执行，执行完成后需要等flannel 的pods 运行起来，这需要点时间：
[root@docker-server1 ~]# wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
[root@docker-server1 ~]# sed -i 's@quay.io@quay.azk8s.cn@g' kube-flannel.yml
[root@docker-server1 ~]# kubectl apply -f kube-flannel.yml
podsecuritypolicy.policy/psp.flannel.unprivileged created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds-amd64 created
daemonset.apps/kube-flannel-ds-arm64 created
daemonset.apps/kube-flannel-ds-arm created
daemonset.apps/kube-flannel-ds-ppc64le created
daemonset.apps/kube-flannel-ds-s390x created
[root@docker-server1 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
192.168.200.111 Ready master 9m24s v1.17.3
已经是ready状态
2.9、安装node节点
安装node方式一：
可以根据master安装时的提示信息
kubeadm join 192.168.200.111:6443 --token abcdef.0123456789abcdef \
--discovery-token-ca-cert-hash sha256:c2d6067d5c3b12118275958dee222226d09a89fc5fb559687dc989d2508d5a50
安装node方式二：
master节点查看token信息
[root@docker-server1 ~]# cat kubeadm-config.yaml |grep token
- system:bootstrappers:kubeadm:default-node-token
token: abcdef.0123456789abcdef
docker-server2主机：
[root@docker-server2 ~]# kubeadm config print join-defaults > kubeadm-config.yaml
[root@docker-server2 ~]# vim kubeadm-config.yaml
apiVersion: kubeadm.k8s.io/v1beta2
caCertPath: /etc/kubernetes/pki/ca.crt
discovery:
bootstrapToken:
apiServerEndpoint: 192.168.200.111:6443
token: abcdef.0123456789abcdef
unsafeSkipCAVerification: true
timeout: 5m0s
tlsBootstrapToken: abcdef.0123456789abcdef
kind: JoinConfiguration
nodeRegistration:
criSocket: /var/run/dockershim.sock
name: 192.168.200.112
taints: null
[root@docker-server2 ~]# kubeadm join --config kubeadm-config.yaml
W0212 22:13:36.627811 3819 join.go:346] [preflight] WARNING: JoinControlPane.controlPlane settings will be ignored when
control-plane flag is not set.[preflight] Running pre-flight checks
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd
". Please follow the guide at https://kubernetes.io/docs/setup/cri/[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
[kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.17" ConfigMap in the kube-system names
pace[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Starting the kubelet
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
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.
docker-server3主机：
[root@docker-server3 ~]# kubeadm config print join-defaults > kubeadm-config.yaml
[root@docker-server3 ~]# vim kubeadm-config.yaml
apiVersion: kubeadm.k8s.io/v1beta2
caCertPath: /etc/kubernetes/pki/ca.crt
discovery:
bootstrapToken:
apiServerEndpoint: 192.168.200.111:6443
token: abcdef.0123456789abcdef
unsafeSkipCAVerification: true
timeout: 5m0s
tlsBootstrapToken: abcdef.0123456789abcdef
kind: JoinConfiguration
nodeRegistration:
criSocket: /var/run/dockershim.sock
name: 192.168.200.112
taints: null
[root@docker-server3 ~]# kubeadm join --config kubeadm-config.yaml
W0212 22:13:38.565506 3838 join.go:346] [preflight] WARNING: JoinControlPane.controlPlane settings will be ignored when
control-plane flag is not set.[preflight] Running pre-flight checks
[WARNING IsDockerSystemdCheck]: detected "cgroupfs" as the Docker cgroup driver. The recommended driver is "systemd
". Please follow the guide at https://kubernetes.io/docs/setup/cri/[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
[kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.17" ConfigMap in the kube-system names
pace[kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
[kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
[kubelet-start] Starting the kubelet
[kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
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.
master查看node节点信息
[root@docker-server1 ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
192.168.200.111 Ready master 17m v1.17.3
192.168.200.112 Ready <none> 111s v1.17.3
192.168.200.113 Ready <none> 109s v1.17.3
master查看Pod信息
[root@docker-server1 ~]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-7f9c544f75-6b8gq 1/1 Running 0 17m
coredns-7f9c544f75-tjg2l 1/1 Running 0 17m
etcd-192.168.200.111 1/1 Running 0 17m
kube-apiserver-192.168.200.111 1/1 Running 0 17m
kube-controller-manager-192.168.200.111 1/1 Running 0 17m
kube-flannel-ds-amd64-bl49r 1/1 Running 3 2m24s
kube-flannel-ds-amd64-dfkgr 1/1 Running 0 9m14s
kube-flannel-ds-amd64-j74w7 1/1 Running 0 2m26s
kube-proxy-442vz 1/1 Running 0 2m26s
kube-proxy-trrsg 1/1 Running 0 17m
kube-proxy-xnn74 1/1 Running 0 2m24s
kube-scheduler-192.168.200.111 1/1 Running 0 17m
2.10 节点管理命令
以下命令无需执行，仅作为了解
重置master配置
[root@docker-server1 ~]# kubeadm reset
删除node配置
[root@docker-server2 ~]# docker ps -aq|xargs docker rm -f
[root@docker-server2 ~]# systemctl stop kubelet
[root@docker-server2 ~]# rm -rf /etc/kubernetes/*
[root@docker-server2 ~]# rm -rf /var/lib/kubelet/*
三、安装Dashboard UI
3.1、部署Dashboard
dashboard的github仓库地址：https://github.com/kubernetes/dashboard
代码仓库当中，有给出安装示例的相关部署文件，我们可以直接获取之后，直接部署即可
[root@docker-server1 ~]# wget https://raw.githubusercontent.com/kubernetes/dashboard/master/aio/deploy/recommended.yaml
默认这个部署文件当中，会单独创建一个名为kubernetes-dashboard的命名空间，并将kubernetes-dashboard部署在该命名空间下。dashboard的镜像来自docker hub官方，所以可不用修改镜像地址，直接从官方获取即可。
3.2、开放端口设置
在默认情况下，dashboard并不对外开放访问端口，这里简化操作，直接使用nodePort的方式将其端口暴露出来，修改serivce部分的定义：
[root@docker-server1 ~]# vim recommended.yaml
kind: Service
apiVersion: v1
metadata:
labels:
k8s-app: kubernetes-dashboard
name: kubernetes-dashboard
namespace: kubernetes-dashboard
spec:
type: NodePort #添加
ports:
- port: 443
targetPort: 8443
nodePort: 32443 #添加
selector:
k8s-app: kubernetes-dashboard
3.3、权限配置
由于这个权限太小，修改一个超级管理员权限
[root@docker-server1 ~]# vim recommended.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: kubernetes-dashboard
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: kubernetes-dashboard
namespace: kubernetes-dashboard
[root@docker-server1 ~]# kubectl apply -f recommended.yaml
namespace/kubernetes-dashboard created
serviceaccount/kubernetes-dashboard created
service/kubernetes-dashboard created
secret/kubernetes-dashboard-certs created
secret/kubernetes-dashboard-csrf created
secret/kubernetes-dashboard-key-holder created
configmap/kubernetes-dashboard-settings created
role.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrole.rbac.authorization.k8s.io/kubernetes-dashboard created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard created
deployment.apps/kubernetes-dashboard created
service/dashboard-metrics-scraper created
deployment.apps/dashboard-metrics-scraper created
获取token
[root@docker-server1 ~]# kubectl describe secret -n kubernetes-dashboard $(kubectl get secret -n kubernetes-dashboard |grep kubernetes-dashboard-token | awk '{print $1}') |grep token | awk '{print $2}'
kubernetes-dashboard-token-fk762
kubernetes.io/service-account-token
eyJhbGciOiJSUzI1NiIsImtpZCI6Ik5aYmhQMDA4aktaeUVyQVpBd3Y5VUNsTXFQV1VBeTRhSml4ZWlmNUV2NzAifQ.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.J_XYUsmSB1wWApYQkSebgd3BvEHoZe5pBgayw8N0xG6TYBsPhMEBVyhE6pR-P-R2eZKPAK9xkajMIwxtwxnIi2NTPv--FiecLINj2_XV7pegkEmd7AREXEPQmjGqM3Fulc7VkVFaG1YIdRmgi069GImpqFuTF0t19wOaloetUHY6LMRJsyHyesjvc2V82a_qgrFNcVtw9l0b8HhxebRIH6crhCMXKRpsjeF8zUg-Aq4ZfJxxEcc6wM2bOzAh00vJECHKBc7sTH2va8xic7GL_hMyE5SZzSOVeaulODWCc5hQdSc2BxeY4TVFz6GJXDC6ZgVj8gnNgUXxw3NVSiDmyg
使用token登录系统
到此K8S集群安装全部完成
四、应用部署测试
下面我们部署一个简单的Nginx WEB服务，该容器运行时会监听80端口，同时访问/info路径会显示容器的主机名。服务由3个容器实例构成，并且通过Nodeport方式暴露给用户。
[root@docker-server1 ~]# kubectl run nginxweb --image=nginx --port=80 --replicas=3
kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead.deployment.apps/nginxweb created
查看创建的对象，可以看到已经有3个pod在运行了
[root@docker-server1 ~]# kubectl get deployment
NAME READY UP-TO-DATE AVAILABLE AGE
nginxweb 0/3 3 0 14s
[root@docker-server1 ~]# kubectl get po
NAME READY STATUS RESTARTS AGE
nginxweb-6d7457b898-5qcbs 0/1 ContainerCreating 0 31s
nginxweb-6d7457b898-m5tvh 0/1 ContainerCreating 0 31s
nginxweb-6d7457b898-v58bj 0/1 ContainerCreating 0 31s
创建svc，通过Nodeport方式暴露服务
[root@docker-server1 ~]# kubectl expose deployment nginxweb --name=nginxwebsvc --port=80 --target-port=80 --type=NodePort
service/nginxwebsvc exposed
查看svc，可以看到NodePort随机分配的端口为30715
[root@docker-server1 ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 147m
nginxwebsvc NodePort 10.96.63.33 <none> 80:30715/TCP 52s
接下来，在用户操作系统就可以通过master主机的ip地址 http://192.168.200.111:30715/ 来访问这个nginxwebsvc了，nginxwebsvc 会把80口的请求再负载均衡到实际的nginxweb pod上
以上就是Kubeadm部署Kubernetes集群的步骤，详细使用情况还需要大家自己亲自动手使用过才能领会。如果想了解更多相关内容，欢迎关注天达云行业资讯频道！