kubernetes集群部署
kubernetes集群部署
- Kubernetes是什么
- Kubernetes集群架构与组件
- 快速部署一个Kubernetes集群
-
- 生产环境部署K8s的2种方式
- 服务器硬件配置推荐
- 使用kubeadm快速部署一个K8s集群
- 部署的网络组件起什么作用?
- 查看集群状态
- Kubernetes将弃用Docker
- kubernetes快速部署
-
- 安装要求
- 学习目标
- 准备环境
- 所有节点安装Docker/kubeadm/kubelet
-
- 安装Docker
- 添加kubernetes阿里云YUM软件源
- 安装kubeadm，kubelet和kubectl
- 部署Kubernetes Master
- 安装Pod网络插件（CNI）
- 加入Kubernetes Node
- 测试kubernetes集群
Kubernetes是什么
Kubernetes是Google在2014年开源的一个容器集群管理系统，Kubernetes简称K8s。. Kubernetes用于容器化应用程序的部署，扩展和管理，目标是让部署容器化应用简单高效。
官方网站
官方文档
Kubernetes集群架构与组件
Master组件
- kube-apiserver
Kubernetes APl，集群的统一入口，各组件协调者，以RESTfulAPI提供接口服务，所有对象资源的增删改查和监听操作都交给APlServer处理后再提交给Etcd存储。 - kube-controller-manager
处理集群中常规后台任务，一个资源对应一个控制器，而ControllerManager就是负责管理这些控制器的。 - kube-scheduler（调度器）
根据调度算法为新创建的Pod选择一个Node节点，可以任意部署,可以部署在同一个节点上,也可以部署在不同的节点上。 - etcd
分布式键值存储系统。用于保存集群状态数据，比如Pod、Service等对象信息。
Node组件
- kubelet
kubelet是Master在Node节点上的Agent，管理本机运行容器的生命周期，比如创建容器、Pod挂载数据卷、下载secret、获取容器和节点状态等工作。kubelet将每个Pod转换成一组容器。 - kube-proxy
在Node节点上实现Pod网络代理，维护网络规则和四层负载均衡工作。 - docker或rocket
容器引擎，运行容器。
快速部署一个Kubernetes集群
- 生产环境部署K8s的2种方式
- 服务器硬件配置推荐
- 使用kubeadm快速部署一个K8s集群
- 部署的网络组件起什么作用?
- 查看集群状态
- Kubernetes将弃用Docker
生产环境部署K8s的2种方式
- kubeadm
Kubeadm是一个工具，提供kubeadm init和kubeadm join，用于快速部署Kubernetes集群。部署地址: https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm/ - 二进制
从官方下载发行版的二进制包，手动部署每个组件，组成Kubernetes集群。下载地址: https://github.com/kubernetes/kubernetes/releases
服务器硬件配置推荐
使用kubeadm快速部署一个K8s集群
- 安装Docker
- 创建一个 Master节点kubeadm init
- 将一个Node节点加入到当前集群中
kubeadm join - 部署容器网络(CNI)
kubectl apply -f calico.yaml - 部署Web UI (Dashboard)
部署的网络组件起什么作用?
部署网络组件的目的是打通Pod到Pod之间网络、Node与Pod之间网络，从而集群中数据包可以任意传输，形成了一个扁平化网络。
主流网络组件有:Flannel、Calico等
而所谓的CNI ( Container Network Interface，容器网络接口）就是k8s对接这些第三方网络组件的接口。
查看集群状态
查看master组件状态:
kubectl get cs
查看node状态:
kubectl get node
查看Apiserver代理的URL:
kubectl cluster-info
查看集群详细信息:
kubectl cluster-info dump
查看资源信息:
kubectl describe<资源><名称>
Kubernetes将弃用Docker
在Kubernetes平台中，为了解决与容器运行时（例如Docker)集成问题，在早期社区推出了CRI (Container Runtime Interface，容器运行时接口)，以支持更多的容器运行时。
当我们使用Docker作为容器运行时之后，架构是这样的，如图所示:
Kubernetes 计划弃用就是kubelet中dockershim。即 Kuberneteskubelet实现中的组件之一，它能够与Docker Engine 进行通信。
为什么这么做？
Docker内部调用链比较复杂，多层封装和调用，导致性能降低、提升故障率、不易排查
Docker还会在宿主机创建网络规则、存储卷，也带来了安全隐患
如何应对?
在未来的Kubernetes 版本彻底放弃Docker支持之前，引入受支持的容器运行时。除了docker之外，CRl还支持很多容器运行时，例如:
- containerd：containerd与Docker相兼容，相比Docker轻量很多，目前较为成熟
- cri-o，podman：都是红帽(RedHat)项目，目前红帽主推podman
kubernetes快速部署
kubeadm是官方社区推出的一个用于快速部署kubernetes集群的工具。这个工具能通过两条指令完成一个kubernetes集群的部暑︰
# 创建一个 Master 节点
$ kubeadm init
# 将一个 Node 节点加入到当前集群中
$ kubeadm join
安装要求
在开始之前，部署Kubernetes集群机器需要满足以下几个条件:
至少3台机器，操作系统CentOS7+
- 硬件配置:2GB或更多RAM，2个CPU或更多CPU，硬盘20GB或更多
- 集群中所有机器之间网络互通
- 可以访问外网，需要拉取镜像
- 禁止swap分区
学习目标
- 在所有节点上安装Docker和kubeadm
- 部署Kubernetes Master
- 部署容器网络插件
- 部署Kubernetes Node，将节点加入Kubernetes集群中
- 部署Dashboard Web页面，可视化查看Kubernetes资源
准备环境
| 角色 | IP | 系统 | 需求 |
|---|---|---|---|
| master | 192.168.47.160 | centos 8 | 2核CPU，2G内存 |
| node1 | 192.168.47.161 | centos 7 | 4核CPU，3G内存 |
| node2 | 192.168.47.163 | centos 8 | 4核CPU，3G内存 |
// 关闭防火墙和selinux
[root@master ~]# systemctl disable --now firewalld
[root@master ~]# sed -i 's/enforcing/disabled/' /etc/selinux/config
[root@node1 ~]# systemctl disable --now firewalld
[root@node1 ~]# sed -i 's/enforcing/disabled/' /etc/selinux/config
[root@node2 ~]# systemctl disable --now firewalld
[root@node2 ~]# sed -i 's/enforcing/disabled/' /etc/selinux/config
// 关闭swap
注释掉或删掉swap分区（我这里是注释掉的）
[root@master ~]# vim /etc/fstab
#/dev/mapper/cs-swap none swap defaults 0 0
[root@node1 ~]# vim /etc/fstab
#/dev/mapper/centos-swap swap swap defaults 0 0
[root@node2 ~]# vim /etc/fstab
#/dev/mapper/cs-swap none swap defaults 0 0
// 设置主机名
[root@localhost ~]# hostnamectl set-hostname master.example.com
[root@localhost ~]# bash
[root@master ~]# hostname
master.example.com
[root@localhost ~]# hostnamectl set-hostname node1.example.com
[root@localhost ~]# bash
[root@node1 ~]# hostname
node1.example.com
[root@localhost ~]# hostnamectl set-hostname node2.example.com
[root@localhost ~]# bash
[root@node2 ~]# hostname
node2.example.com
// 在master添加hosts
[root@master ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.47.160 master master.example.com
192.168.47.161 node1 node1.example.com
192.168.47.163 node2 node2.example.com
// 将桥接的IPv4流量传递到iptables的链
[root@master ~]# cat > /etc/sysctl.d/k8s.conf << EOF
> net.bridge.bridge-nf-call-ip6tables = 1
> net.bridge.bridge-nf-call-iptables = 1
> EOF
[root@master ~]# sysctl --system # 生效
// 时间同步
[root@master ~]# yum -y install chrony
[root@master ~]# vim /etc/chrony.conf
3 pool time1.aliyun.com iburst
[root@master ~]# systemctl enable --now chronyd
[root@node1 ~]# yum -y install chrony
[root@node1 ~]# vim /etc/chrony.conf
3 server time1.aliyun.com iburst
4 #server 0.centos.pool.ntp.org iburst
5 #server 1.centos.pool.ntp.org iburst
6 #server 2.centos.pool.ntp.org iburst
7 #server 3.centos.pool.ntp.org iburst
[root@node1 ~]# systemctl enable --now chronyd
[root@node2 ~]# yum -y install chrony
[root@node2 ~]# vim /etc/chrony.conf
3 pool time1.aliyun.com iburst
[root@node2 ~]# systemctl enable --now chronyd
// 免密认证
[root@master ~]# ssh-keygen -t rsa
[root@master ~]# ssh-copy-id master
[root@master ~]# ssh-copy-id node1
[root@master ~]# ssh-copy-id node2
// 测试
[root@master ~]# for i in master node1 node2;do ssh $i 'date';done
2021年 12月 17日 星期五 23:47:59 CST
2021年 12月 17日 星期五 23:47:59 CST
2021年 12月 17日 星期五 23:47:59 CST
// 重启让刚刚的操作生效
[root@master ~]# reboot
[root@node1 ~]# reboot
[root@node2 ~]# reboot
所有节点安装Docker/kubeadm/kubelet
Kubernetes默认CRI（容器运行时）为Docker，因此先安装Docker。
安装Docker
// 下载docker源
[root@master ~]# cd /etc/yum.repos.d/
[root@master yum.repos.d]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
[root@node1 ~]# cd /etc/yum.repos.d/
[root@node1 yum.repos.d]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
[root@node2 ~]# cd /etc/yum.repos.d/
[root@node2 yum.repos.d]# wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo
// 安装docker
[root@master ~]# yum -y install docker-ce
[root@node1 ~]# yum -y install docker-ce
[root@node2 ~]# yum -y install docker-ce
// 设置docker开机自启
[root@master ~]# systemctl enable --now docker
Created symlink /etc/systemd/system/multi-user.target.wants/docker.service → /usr/lib/systemd/system/docker.service.
[root@node1 ~]# systemctl enable --now docker
Created symlink /etc/systemd/system/multi-user.target.wants/docker.service → /usr/lib/systemd/system/docker.service.
[root@node2 ~]# systemctl enable --now docker
Created symlink /etc/systemd/system/multi-user.target.wants/docker.service → /usr/lib/systemd/system/docker.service.
// 查看docker版本号
[root@master ~]# docker --version
Docker version 20.10.12, build e91ed57
[root@node1 ~]# docker --version
Docker version 20.10.12, build e91ed57
[root@node2 ~]# docker --version
Docker version 20.10.12, build e91ed57
// 设置docker的加速器
[root@master ~]# cat > /etc/docker/daemon.json << EOF
{
"registry-mirrors": ["https://2bkybiwf.mirror.aliyuncs.com"], ## 配置加速器
"exec-opts": ["native.cgroupdriver=systemd"], ## 用systemd的方式来管理cgroup
"log-driver": "json-file", ## 日志格式用json
"log-opts": {
"max-size": "100m" ## 最大的大小100M，达到100M就滚动
},
"storage-driver": "overlay2" ## 存储驱动用overlay2
}
EOF
[root@node1 ~]# cat > /etc/docker/daemon.json << EOF
> {
> "registry-mirrors": ["https://2bkybiwf.mirror.aliyuncs.com"],
> "exec-opts": ["native.cgroupdriver=systemd"],
> "log-driver": "json-file",
> "log-opts": {
> "max-size": "100m"
> },
> "storage-driver": "overlay2"
> }
> EOF
[root@node2 ~]# cat > /etc/docker/daemon.json << EOF
> {
> "registry-mirrors": ["https://2bkybiwf.mirror.aliyuncs.com"],
> "exec-opts": ["native.cgroupdriver=systemd"],
> "log-driver": "json-file",
> "log-opts": {
> "max-size": "100m"
> },
> "storage-driver": "overlay2"
> }
> EOF
添加kubernetes阿里云YUM软件源
[root@master ~]# cat > /etc/yum.repos.d/kubernetes.repo << EOF
> [kubernetes]
> name=Kubernetes
> baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
> enabled=1
> gpgcheck=0
> repo_gpgcheck=0
> gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
> EOF
[root@master ~]# dnf clean all
[root@master ~]# dnf makecache
[root@node1 ~]# cat > /etc/yum.repos.d/kubernetes.repo << EOF
> [kubernetes]
> name=Kubernetes
> baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
> enabled=1
> gpgcheck=0
> repo_gpgcheck=0
> gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
> EOF
[root@node1 ~]# dnf clean all
[root@node1 ~]# dnf makecache
[root@node2 ~]# cat > /etc/yum.repos.d/kubernetes.repo << EOF
> [kubernetes]
> name=Kubernetes
> baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
> enabled=1
> gpgcheck=0
> repo_gpgcheck=0
> gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
> EOF
[root@node2 ~]# dnf clean all
[root@node2 ~]# dnf makecache
安装kubeadm，kubelet和kubectl
由于版本更新频繁，这里指定版本号部署：
[root@master ~]# yum install -y kubelet-1.20.0 kubeadm-1.20.0 kubectl-1.20.0
[root@master ~]# systemctl enable kubelet
Created symlink /etc/systemd/system/multi-user.target.wants/kubelet.service → /usr/lib/systemd/system/kubelet.service.
[root@node1 ~]# yum install -y kubelet-1.20.0 kubeadm-1.20.0 kubectl-1.20.0
[root@node1 ~]# systemctl enable kubelet
Created symlink /etc/systemd/system/multi-user.target.wants/kubelet.service → /usr/lib/systemd/system/kubelet.service.
[root@node2 ~]# yum install -y kubelet-1.20.0 kubeadm-1.20.0 kubectl-1.20.0
[root@node2 ~]# systemctl enable kubelet
Created symlink /etc/systemd/system/multi-user.target.wants/kubelet.service → /usr/lib/systemd/system/kubelet.service.
部署Kubernetes Master
在192.168.122.131（Master）执行。
[root@master ~]# kubeadm init --apiserver-advertise-address=192.168.47.160 --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.20.0 --service-cidr=10.96.0.0/12 --pod-network-cidr=10.244.0.0/16
[init] Using Kubernetes version: v1.20.0
[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/
[WARNING FileExisting-tc]: tc not found in system path
[WARNING SystemVerification]: this Docker version is not on the list of validated versions: 20.10.12. Latest validated version: 19.03
[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'
[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 [kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local master.example.com] and IPs [10.96.0.1 192.168.47.160]
[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 [localhost master.example.com] and IPs [192.168.47.160 127.0.0.1 ::1]
[certs] Generating "etcd/peer" certificate and key
[certs] etcd/peer serving cert is signed for DNS names [localhost master.example.com] and IPs [192.168.47.160 127.0.0.1 ::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
[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
[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"
[control-plane] Creating static Pod manifest for "kube-scheduler"
[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/manifests". This can take up to 4m0s
[apiclient] All control plane components are healthy after 8.503152 seconds
[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[kubelet] Creating a ConfigMap "kubelet-config-1.20" in namespace kube-system with the configuration for the kubelets in the cluster
[upload-certs] Skipping phase. Please see --upload-certs
[mark-control-plane] Marking the node master.example.com as control-plane by adding the labels "node-role.kubernetes.io/master=''" and "node-role.kubernetes.io/control-plane='' (deprecated)"
[mark-control-plane] Marking the node master.example.com as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
[bootstrap-token] Using token: 1f7l8p.opg4o9u8in5rq5yp
[bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to get nodes
[bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap 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: ## 如果是普通用户就运行下面三条命令
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
Alternatively, if you are the root user, you can run: ## 如果是管理员就运行下面一条命令
export KUBECONFIG=/etc/kubernetes/admin.conf
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:
## 把下面这段写进一个文件里面先
kubeadm join 192.168.47.160:6443 --token 1f7l8p.opg4o9u8in5rq5yp \
--discovery-token-ca-cert-hash sha256:3b4c00837e5ce13b487e894a230a4d9204f2a8d3885abe2bee8b9eacd51a4990
[root@master ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
registry.aliyuncs.com/google_containers/kube-proxy v1.20.0 10cc881966cf 12 months ago 118MB
registry.aliyuncs.com/google_containers/kube-apiserver v1.20.0 ca9843d3b545 12 months ago 122MB
registry.aliyuncs.com/google_containers/kube-controller-manager v1.20.0 b9fa1895dcaa 12 months ago 116MB
registry.aliyuncs.com/google_containers/kube-scheduler v1.20.0 3138b6e3d471 12 months ago 46.4MB
registry.aliyuncs.com/google_containers/etcd 3.4.13-0 0369cf4303ff 15 months ago 253MB
registry.aliyuncs.com/google_containers/coredns 1.7.0 bfe3a36ebd25 18 months ago 45.2MB
registry.aliyuncs.com/google_containers/pause 3.2 80d28bedfe5d 22 months ago 683kB
[root@master ~]# cat init
kubeadm join 192.168.47.160:6443 --token 1f7l8p.opg4o9u8in5rq5yp \
--discovery-token-ca-cert-hash sha256:3b4c00837e5ce13b487e894a230a4d9204f2a8d3885abe2bee8b9eacd51a4990
由于默认拉取镜像地址k8s.gcr.io国内无法访问，这里指定阿里云镜像仓库地址。
使用kubectl工具：
// 让环境变量永久生效
[root@master ~]# echo 'export KUBECONFIG=/etc/kubernetes/admin.conf' > /etc/profile.d/k8s.sh
[root@master ~]# source /etc/profile.d/k8s.sh
// 查看是否有控制节点
[root@master ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master.example.com NotReady control-plane,master 13m v1.20.0
安装Pod网络插件（CNI）
// 下载kube-flannel.yml
[root@master ~]# ls
anaconda-ks.cfg init kube-flannel.yml
[root@master ~]# 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 created
确保能够访问到quay.io这个registery。
加入Kubernetes Node
在192.168.47.161、192.168.47.163上（Node）执行。
向集群添加新节点，执行在kubeadm init输出的kubeadm join命令：
// 把刚刚保存的文件复制到node1和node2上去执行，拉镜像
[root@master ~]# cat init
kubeadm join 192.168.47.160:6443 --token 1f7l8p.opg4o9u8in5rq5yp \
--discovery-token-ca-cert-hash sha256:3b4c00837e5ce13b487e894a230a4d9204f2a8d3885abe2bee8b9eacd51a4990
[root@node1 ~]# kubeadm join 192.168.47.160:6443 --token 1f7l8p.opg4o9u8in5rq5yp \
> --discovery-token-ca-cert-hash sha256:3b4c00837e5ce13b487e894a230a4d9204f2a8d3885abe2bee8b9eacd51a4990
[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/
[WARNING SystemVerification]: this Docker version is not on the list of validated versions: 20.10.12. Latest validated version: 19.03
[WARNING Hostname]: hostname "node1.example.com" could not be reached
[WARNING Hostname]: hostname "node1.example.com": lookup node1.example.com on 192.168.47.2:53: no such host
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[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.
[root@node2 ~]# kubeadm join 192.168.47.160:6443 --token 1f7l8p.opg4o9u8in5rq5yp \
> --discovery-token-ca-cert-hash sha256:3b4c00837e5ce13b487e894a230a4d9204f2a8d3885abe2bee8b9eacd51a4990
[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/
[WARNING FileExisting-tc]: tc not found in system path
[WARNING SystemVerification]: this Docker version is not on the list of validated versions: 20.10.12. Latest validated version: 19.03
[WARNING Hostname]: hostname "node2.example.com" could not be reached
[WARNING Hostname]: hostname "node2.example.com": lookup node2.example.com on 192.168.47.2:53: server misbehaving
[preflight] Reading configuration from the cluster...
[preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[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.
// 查看，下面node2还是notready，是因为它的后台还有东西在运行，等一会就可以了，等它变成ready
[root@master ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master.example.com Ready control-plane,master 25m v1.20.0
node1.example.com Ready <none> 2m37s v1.20.0
node2.example.com NotReady <none> 2m18s v1.20.0
// 三个全都是ready之后，集群就部署好了
[root@master ~]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
master.example.com Ready control-plane,master 27m v1.20.0
node1.example.com Ready <none> 4m14s v1.20.0
node2.example.com Ready <none> 3m55s v1.20.0
//在node1和node2上查看镜像
[root@node1 ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
quay.io/coreos/flannel v0.15.1 e6ea68648f0c 4 weeks ago 69.5MB
rancher/mirrored-flannelcni-flannel-cni-plugin v1.0.0 cd5235cd7dc2 7 weeks ago 9.03MB
registry.aliyuncs.com/google_containers/kube-proxy v1.20.0 10cc881966cf 12 months ago 118MB
registry.aliyuncs.com/google_containers/pause 3.2 80d28bedfe5d 22 months ago 683kB
[root@node2 ~]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
quay.io/coreos/flannel v0.15.1 e6ea68648f0c 4 weeks ago 69.5MB
rancher/mirrored-flannelcni-flannel-cni-plugin v1.0.0 cd5235cd7dc2 7 weeks ago 9.03MB
registry.aliyuncs.com/google_containers/kube-proxy v1.20.0 10cc881966cf 12 months ago 118MB
registry.aliyuncs.com/google_containers/pause 3.2 80d28bedfe5d 22 months ago 683kB
// 部署好之后，node1和node2上会自动运行一些容器
[root@node1 ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
90be46c739f6 e6ea68648f0c "/opt/bin/flanneld -…" 6 minutes ago Up 6 minutes k8s_kube-flannel_kube-flannel-ds-9kxkg_kube-system_4f152d43-a1bd-4293-b3bf-be89715538fa_0
436d9e9e7d06 quay.io/coreos/flannel "cp -f /etc/kube-fla…" 6 minutes ago Exited (0) 6 minutes ago k8s_install-cni_kube-flannel-ds-9kxkg_kube-system_4f152d43-a1bd-4293-b3bf-be89715538fa_0
475e701c89ab rancher/mirrored-flannelcni-flannel-cni-plugin "cp -f /flannel /opt…" 6 minutes ago Exited (0) 6 minutes ago k8s_install-cni-plugin_kube-flannel-ds-9kxkg_kube-system_4f152d43-a1bd-4293-b3bf-be89715538fa_0
e6e5b73a1e48 registry.aliyuncs.com/google_containers/kube-proxy "/usr/local/bin/kube…" 7 minutes ago Up 7 minutes k8s_kube-proxy_kube-proxy-cxr8n_kube-system_8129a25c-3feb-4fc0-82bb-1927db0f1854_0
2b9e1a8828e6 registry.aliyuncs.com/google_containers/pause:3.2 "/pause" 7 minutes ago Up 7 minutes k8s_POD_kube-flannel-ds-9kxkg_kube-system_4f152d43-a1bd-4293-b3bf-be89715538fa_0
a0419097243f registry.aliyuncs.com/google_containers/pause:3.2 "/pause" 7 minutes ago Up 7 minutes k8s_POD_kube-proxy-cxr8n_kube-system_8129a25c-3feb-4fc0-82bb-1927db0f1854_0
[root@node2 ~]# docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f2b7159cdf74 e6ea68648f0c "/opt/bin/flanneld -…" 5 minutes ago Up 5 minutes k8s_kube-flannel_kube-flannel-ds-j6mnd_kube-system_50c1a168-d23d-44a9-823f-bcd661f9d971_0
ff6eb0721822 quay.io/coreos/flannel "cp -f /etc/kube-fla…" 5 minutes ago Exited (0) 5 minutes ago k8s_install-cni_kube-flannel-ds-j6mnd_kube-system_50c1a168-d23d-44a9-823f-bcd661f9d971_0
95cf338b10a2 rancher/mirrored-flannelcni-flannel-cni-plugin "cp -f /flannel /opt…" 6 minutes ago Exited (0) 6 minutes ago k8s_install-cni-plugin_kube-flannel-ds-j6mnd_kube-system_50c1a168-d23d-44a9-823f-bcd661f9d971_0
9f8c52aa64a5 registry.aliyuncs.com/google_containers/kube-proxy "/usr/local/bin/kube…" 7 minutes ago Up 7 minutes k8s_kube-proxy_kube-proxy-tk9zw_kube-system_761d9ed2-d1ae-42ad-93b5-cb97a503e243_0
6914dcb035f5 registry.aliyuncs.com/google_containers/pause:3.2 "/pause" 7 minutes ago Up 7 minutes k8s_POD_kube-flannel-ds-j6mnd_kube-system_50c1a168-d23d-44a9-823f-bcd661f9d971_0
8d0f91297c9e registry.aliyuncs.com/google_containers/pause:3.2 "/pause" 7 minutes ago Up 7 minutes k8s_POD_kube-proxy-tk9zw_kube-system_761d9ed2-d1ae-42ad-93b5-cb97a503e243_0
//查看名称空间
[root@master ~]# kubectl get ns
NAME STATUS AGE
default Active 33m
kube-node-lease Active 33m
kube-public Active 33m
kube-system Active 33m
// 指定名称空间去看pods的信息
[root@master ~]# kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-7f89b7bc75-8gff5 1/1 Running 0 34m
coredns-7f89b7bc75-d5hs6 1/1 Running 0 34m
etcd-master.example.com 1/1 Running 0 34m
kube-apiserver-master.example.com 1/1 Running 0 34m
kube-controller-manager-master.example.com 1/1 Running 0 34m
kube-flannel-ds-9kxkg 1/1 Running 0 11m
kube-flannel-ds-j6mnd 1/1 Running 0 11m
kube-flannel-ds-zw62f 1/1 Running 0 15m
kube-proxy-cxr8n 1/1 Running 0 11m
kube-proxy-mhvn6 1/1 Running 0 34m
kube-proxy-tk9zw 1/1 Running 0 11m
kube-scheduler-master.example.com 1/1 Running 0 34m
// 查看pods在哪运行
[root@master ~]# kubectl get pods -n kube-system -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
coredns-7f89b7bc75-8gff5 1/1 Running 0 38m 10.244.0.2 master.example.com <none> <none>
coredns-7f89b7bc75-d5hs6 1/1 Running 0 38m 10.244.0.3 master.example.com <none> <none>
etcd-master.example.com 1/1 Running 0 38m 192.168.47.160 master.example.com <none> <none>
kube-apiserver-master.example.com 1/1 Running 0 38m 192.168.47.160 master.example.com <none> <none>
kube-controller-manager-master.example.com 1/1 Running 0 38m 192.168.47.160 master.example.com <none> <none>
kube-flannel-ds-9kxkg 1/1 Running 0 15m 192.168.47.161 node1.example.com <none> <none>
kube-flannel-ds-j6mnd 1/1 Running 0 15m 192.168.47.163 node2.example.com <none> <none>
kube-flannel-ds-zw62f 1/1 Running 0 19m 192.168.47.160 master.example.com <none> <none>
kube-proxy-cxr8n 1/1 Running 0 15m 192.168.47.161 node1.example.com <none> <none>
kube-proxy-mhvn6 1/1 Running 0 38m 192.168.47.160 master.example.com <none> <none>
kube-proxy-tk9zw 1/1 Running 0 15m 192.168.47.163 node2.example.com <none> <none>
kube-scheduler-master.example.com 1/1 Running 0 38m 192.168.47.160 master.example.com <none> <none>
测试kubernetes集群
在Kubernetes集群中创建一个pod，验证是否正常运行：
[root@master ~]# kubectl create deployment nginx --image nginx
deployment.apps/nginx created
[root@master ~]# kubectl expose deployment nginx --port=80 --type=NodePort ## 暴露端口号，暴露的是service的端口号，不能用pod的IP地址去访问，也不能用pod的主机名去访问，要访问的话只能用service访问
service/nginx exposed
// 查看service的IP
[root@master ~]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 77m
nginx NodePort 10.111.4.86 <none> 80:30859/TCP 36m
[root@master ~]# kubectl get pods,svc
NAME READY STATUS RESTARTS AGE
pod/nginx-6799fc88d8-zrwsl 0/1 ContainerCreating 0 3m8s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 43m
service/nginx NodePort 10.111.4.86 <none> 80:30859/TCP 2m5s
// ping service的IP（这里不知道为什么ping不通，但是后面可以访问得到）
[root@master ~]# ping 10.111.4.86
PING 10.111.4.86 (10.111.4.86) 56(84) bytes of data.
^Z
[5]+ 已停止 ping 10.111.4.86
// 访问service的IP（这里需要等一会访问才能访问到）
[root@master ~]# curl http://10.111.4.86
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
// 查看pod
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-6799fc88d8-zrwsl 1/1 Running 0 32m
//查看pod IP
[root@master ~]# kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-6799fc88d8-zrwsl 1/1 Running 0 33m 10.244.1.2 node1.example.com <none> <none>
// 测试能否ping通（这个IP是随时会变的）
[root@master ~]# ping 10.244.1.2
PING 10.244.1.2 (10.244.1.2) 56(84) bytes of data.
64 bytes from 10.244.1.2: icmp_seq=1 ttl=63 time=0.315 ms
64 bytes from 10.244.1.2: icmp_seq=2 ttl=63 time=0.231 ms
// 测试能否访问
[root@master ~]# curl http://10.244.1.2
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
html { color-scheme: light dark; }
body { width: 35em; margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif; }
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
网页上访问
master IP：service端口号（我这里的端口号是30859）
