# 1. kubeadm部署k8s集群 生产部署k8s一般有两种， kubeadm（官方推荐）和二进制方式，二进制的方式就是以系统守护进程的方式部署集群组件，非常麻烦。kubeadm已容器的方式部署，方便快捷，需要docker、kubelet ## 1.1 环境准备 | 角色 | IP | | --- | --- | | master | 192.168.56.10 | | node1 | 192.168.56.11 | | node2 | 192.168.56.12 | ### 1.1.1 > 初始化域名（三台都需要执行） ``` cat >> /etc/hosts << EOF 192.168.56.10 master 192.168.56.11 node01 192.168.56.12 node02 EOF ``` ### 1.1.2 关闭swap ``` swapoff -a # 临时关闭 sed -ri 's/.*swap.*/#&/' /etc/fstab #永久关闭 ``` ### 1.1.3 关闭防火墙 ``` systemctl stop firewalld systemctl disable firewalld ``` ### 1.1.4 关闭selinux ``` sed -ir 's/SELINUX=.*/SELINUX=disabled/' /etc/selinux/config setenforce 0 ``` &：引用前面的匹配 ### 1.1.5 修改主机名 按照前面的节点规划，修改主机名 ``` hostnamectl set-hostname master hostnamectl set-hostname node01 hostnamectl set-hostname node02 ``` ### 1.1.6. `net.bridge.bridge-nf-call-iptables`设置成1 将桥接的IPv4流量传递到iptables的链 ``` cat <<EOF | sudo tee /etc/modules-load.d/k8s.conf br_netfilter EOF cat <<EOF | sudo tee /etc/sysctl.d/k8s.conf net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 EOF sysctl --system ``` ### 1.1.7 时间同步 ``` yum install ntpdate -y ntpdate -u asia.pool.ntp.org ``` ### 1.1.8 确认`br_netfilter`被加载 ``` [root@10 ~]# modprobe br_netfilter [root@10 ~]# lsmod | grep br_netfilter br_netfilter 22256 0 bridge 151336 2 br_netfilter,ebtable_broute ``` ## 1.2 安装docker、kubeadm、kubectl **首先要安装docker**所有机器都执行，参照docker安装 **1. 这是阿里yum源** * `kubeadm`: the command to bootstrap the cluster. * `kubelet`: the component that runs on all of the machines in your cluster and does things like starting pods and containers. * `kubectl`: the command line util to talk to your cluster. ~~~ 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 ~~~ **2. 安装** ``` yum install -y kubelet-1.18.0 kubeadm-1.18.0 kubectl-1.18.0 ``` **3. 设置开机自启** ``` systemctl enable kubelet ``` ## 1.3 初始化master > maseter =192.168.56.10 > 查看k8s安装版本 ``` [root@master ~]# kubectl version Client Version: version.Info{Major:"1", Minor:"21", GitVersion:"v1.21.2", GitCommit:"092fbfbf53427de67cac1e9fa54aaa09a28371d7", GitTreeState:"clean", BuildDate:"2021-06-16T12:59:11Z", GoVersion:"go1.16.5", Compiler:"gc", Platform:"linux/amd64"} Unable to connect to the server: dial tcp: lookup localhost on 192.168.1.1:53: no such host ``` **1. 初始化，指定从阿里云下载镜像,初始化指定** ``` kubeadm init \ --apiserver-advertise-address=192.168.56.10 \ --image-repository registry.aliyuncs.com/google_containers \ --kubernetes-version v1.18.0 \ --service-cidr=10.1.0.0/16 \ --pod-network-cidr=10.244.0.0/16 ``` 或者配置策略 ``` kubeadm config images pull --image-repository=registry.aliyuncs.com/google_containers ``` 初始化会拉取k8s的master节点所需要镜像  安装成功出现，work节点加入命令 ``` kubeadm join 192.168.56.10:6443 --token u8n2h8.0g939ea9ocjb4kpr \ --discovery-token-ca-cert-hash sha256:f302e0db3e31526748349f67da28f8d099c7d05765059379d885df3f8df13d04 ``` **2. 执行kubectl** ``` mkdir -p $HOME/.kube cp -i /etc/kubernetes/admin.conf $HOME/.kube/config chown $(id -u):$(id -g) $HOME/.kube/config ``` 查看集群信息 ``` [root@master ~]# kubectl cluster-info Kubernetes control plane is running at https://192.168.56.10:6443 CoreDNS is running at https://192.168.56.10:6443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy ``` **3. 加入node节点** 初始化完成后，会出现work节点加入命令，执行即可  ``` kubeadm join 192.168.56.10:6443 --token mhm5x0.uoa7y5v2soxjvn9n \ --discovery-token-ca-cert-hash sha256:5772f81b3f4b88748564d0dddac0f3da813d9a2bde0b1e2ffe36e51c28c8e0f4 ``` **4. 安装CNI插件** 由于限制不能访问，下载原文件再apply ``` kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml ``` **注意：** ，如果是双网卡，需要制定可以转发数据包的网卡 ``` vim kube-flannel.yml # containers 配置下，添加网卡绑定 - --iface=enp0s8 ```  如果已经部署了flannel，则需要`kubectl delete -f kube-flannel.yaml`删除之前的部署，然后执行`kubectl apply -f kube-flannel.yaml`重新部署 安装后，状态变化，但是仍有错误  `kubectl describe pod coredns-59d64cd4d4-2zqkn -n kube-system`  查看master各组件情况，发现controller-manager 、scheduler运行异常  解决办法： cd /etc/kubernetes/manifests vim kube-controller-manager.yaml、kube-scheduler.yaml，将port=0注释掉  起一个pod实验 ``` [root@master manifests]# kubectl run nginx --image=nginx --port=80 pod/nginx created [root@master manifests]# kubectl get pods NAME READY STATUS RESTARTS AGE nginx 0/1 ContainerCreating 0 8s ``` #### 由于虚拟机双网卡造成pod间无法通信 flannel默认绑定第一块网卡，作为转发。由于第一块网卡是外网nat虚拟网卡，无法转发数据包，所以修改默认配置  # 2. 高可用部署 # 3. 集群卸载 ~~~ # 卸载服务 kubeadm reset # 删除rpm包 rpm -qa|grep kube | xargs rpm --nodeps -e # 删除容器及镜像 docker images -qa|xargs docker rmi -f ~~~