前言

最近正在学习k8s集群的搭建过程，记录下来分享给大家。

筹备工作

  • visualbox 虚拟机
  • centos7 ISO镜像
  • 练习的电脑配置要高

搭建kube-master虚拟机

  • 名称：kube-master
  • 内存：4G
  • 硬盘：10G
  • 网卡：网卡1和网卡2





留神：vboxnet0能够在全局网络配置外面点击增加！

搭建过程：略

根本环境配置

  • 敞开selinux
setenforce 0sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config
  • 敞开swap分区或禁用swap文件
swapoff -a# 正文掉对于swap分区的行yes | cp /etc/fstab /etc/fstab_bakcat /etc/fstab_bak |grep -v swap > /etc/fstab
  • 批改网卡配置
$ vim /etc/sysctl.confnet.ipv4.ip_forward = 1net.bridge.bridge-nf-call-iptables = 1net.bridge.bridge-nf-call-ip6tables = 1$ sysctl -p
  • 启用内核模块
$ modprobe -- ip_vs$ modprobe -- ip_vs_rr$ modprobe -- ip_vs_wrr$ modprobe -- ip_vs_sh$ modprobe -- nf_conntrack_ipv4$ cut -f1 -d " "  /proc/modules | grep -e ip_vs -e nf_conntrack_ipv4$ vim /etc/sysconfig/modules/ipvs.modulesmodprobe -- ip_vsmodprobe -- ip_vs_rrmodprobe -- ip_vs_wrrmodprobe -- ip_vs_shmodprobe -- nf_conntrack_ipv4
  • 敞开防火墙
$ systemctl stop firewalld$ systemctl disable firewalld

kubectl、kubeadm、kubelet的装置

  • 增加Kubernetes的yum源
vim /etc/yum.repos.d/kubernetes.repo[kubernetes]name=Kubernetesbaseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64enabled=1gpgcheck=0repo_gpgcheck=0gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
  • 装置kubelet、kubeadm、kubectl
yum install -y kubelet kubeadm kubectl
  • 启动kubelet服务
systemctl enable kubeletsystemctl start kubelet

此时执行systemctl status kubelet查看服务状态，服务状态应为Error(255)， 如果是其余谬误可应用journalctl -xe查看错误信息。

Docker装置和配置

  • Docker装置

docker的装置请查看官网文档

$ sudo yum install -y yum-utils$ sudo yum-config-manager     --add-repo     https://download.docker.com/linux/centos/docker-ce.repo$ sudo yum install docker-ce docker-ce-cli containerd.io $ systemctl enable kubelet$ systemctl start kubelet
  • 配置cgroup-driver为systemd
#查看cgroup-driver$ docker info | grep -i cgroup$ vim /etc/docker/daemon.json{  "registry-mirrors": ["https://xxx.mirror.aliyuncs.com"],  "exec-opts": ["native.cgroupdriver=systemd"]}$ systemctl restart docker#再次查看cgroup-driver，看看是否配置胜利$ docker info | grep -i cgroup

kubeadm装置依赖镜像

这里有篇文章，大家间接参考装置就好！kubeadm装置依赖镜像

以上步骤须要在master节点和node节点执行

配置kube-node-1和kube-node-2虚拟机

  • 复制kube-master虚拟机为kube-node-1和kube-node-2

  • 批改kube-node-1的ip

以下以kube-node-1为例子
启动kube-node-1和kube-node-2虚拟机并登录，输出上面命令行进行批改：

$ vim /etc/sysconfig/network-scripts/ifcfg-enp0s3...IPADDR="10.0.2.21"...
  • 批改kube-node-1的hostname
$ hostnamectl set-hostname kube-node-1
  • 批改/etc/hosts
$ vim /etc/hosts192.168.56.20 kube-master192.168.56.21 kube-node-1192.168.56.22 kube-node-2# 重新启动虚拟机$ poweroff

Master节点的配置

  • Master节点的初始化

首先选用finnel网络插件

kubeadm init --pod-network-cidr=10.244.0.0/16 --kubernetes-version=v1.19.4 --apiserver-advertise-address=192.168.56.20

执行实现之后，输入：

╭─root@kube-master ~╰─# kubeadm init --pod-network-cidr=10.244.0.0/16 --kubernetes-version=v1.19.4 --apiserver-advertise-address=192.168.56.20W1122 15:25:25.160860    2916 configset.go:348] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io][init] Using Kubernetes version: v1.19.4[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'[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 [kube-master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.56.20][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 [kube-master localhost] and IPs [192.168.56.20 127.0.0.1 ::1][certs] Generating "etcd/peer" certificate and key[certs] etcd/peer serving cert is signed for DNS names [kube-master localhost] and IPs [192.168.56.20 127.0.0.1 ::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 13.007285 seconds[upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace[kubelet] Creating a ConfigMap "kubelet-config-1.19" 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 kube-master as control-plane by adding the label "node-role.kubernetes.io/master=''"[mark-control-plane] Marking the node kube-master as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule][bootstrap-token] Using token: dcr14g.bn6134xsgfjm4dun[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-proxyYour Kubernetes control-plane has initialized successfully!To start using your cluster, you need to run the following as a regular user:  mkdir -p $HOME/.kube  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config  sudo chown $(id -u):$(id -g) $HOME/.kube/configYou 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:kubeadm join 192.168.56.20:6443 --token dcr14g.bn6134xsgfjm4dun \    --discovery-token-ca-cert-hash sha256:83e1bbf9c1007f3a0346302ce763b63154694b22e0671f239674352a91c523f3

保留输入中的kubeadm join局部内容，用于增加node节点，或者应用kubeadm token list 和kubeadm token create --print-join-command查看

kubeadm join 192.168.56.20:6443 --token dcr14g.bn6134xsgfjm4dun \    --discovery-token-ca-cert-hash sha256:83e1bbf9c1007f3a0346302ce763b63154694b22e0671f239674352a91c523f3

接下来执行残余的初始化步骤

$ mkdir -p $HOME/.kube# 替换192.168.56.20为kube-master$ vim /etc/kubernetes/admin.conf$ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config$ sudo chown $(id -u):$(id -g) $HOME/.kube/config

查看nodes和pods：

╭─root@kube-master ~╰─# kubectl get nodesNAME          STATUS     ROLES    AGE   VERSIONkube-master   NotReady   master   14m   v1.19.4╭─root@kube-master ~╰─# kubectl get pods --all-namespacesNAMESPACE     NAME                                  READY   STATUS    RESTARTS   AGEkube-system   coredns-f9fd979d6-5vrhh               0/1     Pending   0          13mkube-system   coredns-f9fd979d6-bdwnr               0/1     Pending   0          13mkube-system   etcd-kube-master                      1/1     Running   0          14mkube-system   kube-apiserver-kube-master            1/1     Running   0          14mkube-system   kube-controller-manager-kube-master   1/1     Running   0          14mkube-system   kube-proxy-gcbmf                      1/1     Running   0          13mkube-system   kube-scheduler-kube-master            1/1     Running   0          14m
  • finnel插件的装置
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
╭─root@kube-master ~╰─# kubectl apply -f kube-flannel.ymlpodsecuritypolicy.policy/psp.flannel.unprivileged createdclusterrole.rbac.authorization.k8s.io/flannel createdclusterrolebinding.rbac.authorization.k8s.io/flannel createdserviceaccount/flannel createdconfigmap/kube-flannel-cfg createddaemonset.apps/kube-flannel-ds created

监听查看finnel装置状况：

watch kubectl get pods --all-namespaces
Every 2.0s: kubectl get pods --all-namespaces                                                                                                Sun Nov 22 15:50:24 2020NAMESPACE     NAME                                  READY   STATUS    RESTARTS   AGEkube-system   coredns-f9fd979d6-5vrhh               1/1     Running   0          24mkube-system   coredns-f9fd979d6-bdwnr               1/1     Running   0          24mkube-system   etcd-kube-master                      1/1     Running   0          24mkube-system   kube-apiserver-kube-master            1/1     Running   0          24mkube-system   kube-controller-manager-kube-master   1/1     Running   0          24mkube-system   kube-flannel-ds-s4pm6                 1/1     Running   0          6m49skube-system   kube-proxy-gcbmf                      1/1     Running   0          24mkube-system   kube-scheduler-kube-master            1/1     Running   0          24m

如果两头呈现下载不下来能够参考这篇文章解决：https://blog.csdn.net/zyl9746...

  • 小技巧：

查看kube-flannel-ds-s4pm6装置状况

kubectl describe pods kube-flannel-ds-s4pm6 -n kube-system

  • 测试
╭─root@kube-master ~╰─# kubectl get nodes -o wideNAME          STATUS   ROLES    AGE   VERSION   INTERNAL-IP     EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION           CONTAINER-RUNTIMEkube-master   Ready    master   33m   v1.19.4   192.168.56.20   <none>        CentOS Linux 7 (Core)   3.10.0-1160.el7.x86_64   docker://19.3.13

Node节点的初始化

  • 查看退出集群的命令

要使node节点退出到master节点中，能够先查看master节点生成的退出信息：

╭─root@kube-master ~╰─# kubeadm token create --print-join-commandW1122 16:01:20.660775   18089 configset.go:348] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]kubeadm join kube-master:6443 --token inhs8l.e0otb982o462ruk7     --discovery-token-ca-cert-hash sha256:83e1bbf9c1007f3a0346302ce763b63154694b22e0671f239674352a91c523f3
  • 登录node节点，执行退出集群的命令，实现退出集群操作

以下以kube-node-1为例子

╭─root@kube-node-1 ~╰─# kubeadm join kube-master:6443 --token inhs8l.e0otb982o462ruk7     --discovery-token-ca-cert-hash sha256:83e1bbf9c1007f3a0346302ce763b63154694b22e0671f239674352a91c523f3
  • 查看flannel插件执行状况
kubectl get pods --all-namespaces -o wide


这样就实现了k8s集群的所有操作了！

总结

1、我也观看bilibili大佬的视频总结的，有趣味的能够到这个地址察看视频搭建全过程；
2、k8s须要很多的配置，如果呈现问题大家自行搜寻解决方案，我在搭建的过程中也参考了好多人的文章；

援用

Kubernetes/K8S 集群环境搭建
K8S装置过程笔记