centos7使用kubeadm配置高可用k8s集群的另一种方式

启动etcd集群

在lab1,lab2,lab3节点上启动etcd集群

# lab1 docker stop etcd && docker rm etcd rm -rf /data/etcd mkdir -p /data/etcd docker run -d \ --restart always \ -v /etc/etcd/ssl/certs:/etc/ssl/certs \ -v /data/etcd:/var/lib/etcd \ -p 2380:2380 \ -p 2379:2379 \ --name etcd \ registry.cn-hangzhou.aliyuncs.com/google_containers/etcd-amd64:3.1.12 \ etcd --name=etcd0 \ --advertise-client-urls=http://11.11.11.111:2379 \ --listen-client-urls=http://0.0.0.0:2379 \ --initial-advertise-peer-urls=http://11.11.11.111:2380 \ --listen-peer-urls=http://0.0.0.0:2380 \ --initial-cluster-token=9477af68bbee1b9ae037d6fd9e7efefd \ --initial-cluster=etcd0=http://11.11.11.111:2380,etcd1=http://11.11.11.112:2380,etcd2=http://11.11.11.113:2380 \ --initial-cluster-state=new \ --auto-tls \ --peer-auto-tls \ --data-dir=/var/lib/etcd # lab2 docker stop etcd && docker rm etcd rm -rf /data/etcd mkdir -p /data/etcd docker run -d \ --restart always \ -v /etc/etcd/ssl/certs:/etc/ssl/certs \ -v /data/etcd:/var/lib/etcd \ -p 2380:2380 \ -p 2379:2379 \ --name etcd \ registry.cn-hangzhou.aliyuncs.com/google_containers/etcd-amd64:3.1.12 \ etcd --name=etcd1 \ --advertise-client-urls=http://11.11.11.112:2379 \ --listen-client-urls=http://0.0.0.0:2379 \ --initial-advertise-peer-urls=http://11.11.11.112:2380 \ --listen-peer-urls=http://0.0.0.0:2380 \ --initial-cluster-token=9477af68bbee1b9ae037d6fd9e7efefd \ --initial-cluster=etcd0=http://11.11.11.111:2380,etcd1=http://11.11.11.112:2380,etcd2=http://11.11.11.113:2380 \ --initial-cluster-state=new \ --auto-tls \ --peer-auto-tls \ --data-dir=/var/lib/etcd # lab3 docker stop etcd && docker rm etcd rm -rf /data/etcd mkdir -p /data/etcd docker run -d \ --restart always \ -v /etc/etcd/ssl/certs:/etc/ssl/certs \ -v /data/etcd:/var/lib/etcd \ -p 2380:2380 \ -p 2379:2379 \ --name etcd \ registry.cn-hangzhou.aliyuncs.com/google_containers/etcd-amd64:3.1.12 \ etcd --name=etcd2 \ --advertise-client-urls=http://11.11.11.113:2379 \ --listen-client-urls=http://0.0.0.0:2379 \ --initial-advertise-peer-urls=http://11.11.11.113:2380 \ --listen-peer-urls=http://0.0.0.0:2380 \ --initial-cluster-token=9477af68bbee1b9ae037d6fd9e7efefd \ --initial-cluster=etcd0=http://11.11.11.111:2380,etcd1=http://11.11.11.112:2380,etcd2=http://11.11.11.113:2380 \ --initial-cluster-state=new \ --auto-tls \ --peer-auto-tls \ --data-dir=/var/lib/etcd # 验证查看集群 docker exec -ti etcd ash etcdctl member list etcdctl cluster-health exit 

配置keepalived

在3台master节点操作

# 载入内核相关模块 lsmod | grep ip_vs modprobe ip_vs # 启动keepalived # eth1为本次实验11.11.11.0/24网段的所在网卡 docker run --net=host --cap-add=NET_ADMIN \ -e KEEPALIVED_INTERFACE=eth1 \ -e KEEPALIVED_VIRTUAL_IPS="#PYTHON2BASH:['11.11.11.110']" \ -e KEEPALIVED_UNICAST_PEERS="#PYTHON2BASH:['11.11.11.111','11.11.11.112','11.11.11.113']" \ -e KEEPALIVED_PASSWORD=hello \ --name k8s-keepalived \ --restart always \ -d osixia/keepalived:1.4.4 # 查看日志 # 会看到两个成为backup 一个成为master docker logs k8s-keepalived # 此时会配置 11.11.11.110 到其中一台机器 # ping测试 ping -c4 11.11.11.110 # 如果失败后清理后，重新实验 docker rm -f k8s-keepalived ip a del 11.11.11.110/32 dev eth1 

在第一台master节点初始化

# 生成token # 保留token后面还要使用 token=$(kubeadm token generate) echo $token # 生成配置文件 # advertiseAddress 配置为VIP地址 cat >kubeadm-master.config< containers: - name: kube-flannel image: registry.cn-shanghai.aliyuncs.com/gcr-k8s/flannel:v0.10.0-amd64 command: - /opt/bin/flanneld args: - --ip-masq - --kube-subnet-mgr - --iface=eth1 # 启动 kubectl apply -f kube-flannel.yml # 查看 kubectl get pods -n kube-system kubectl get svc -n kube-system # 设置master允许部署应用pod，参与工作负载，现在可以部署其他系统组件 # 如 dashboard, heapster, efk等 kubectl taint nodes --all node-role.kubernetes.io/master- 

启动其他master节点

# 打包第一台master初始化之后的/etc/kubernetes/pki目录 cd /etc/kubernetes && tar czvf /root/pki.tgz pki/ && cd ~ # 上传到其他master的/etc/kubernetes目录下 tar xf pki.tgz -C /etc/kubernetes/ # 复制启动第一台master时的配置文件到其他master节点 # 初始化 kubeadm init --config kubeadm-master.config systemctl enable kubelet # 配置kubectl使用 mkdir -p $HOME/.kube sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config sudo chown $(id -u):$(id -g) $HOME/.kube/config # 在第一台配置master节点查看 kubectl get pod --all-namespaces -o wide | grep lab1 kubectl get pod --all-namespaces -o wide | grep lab2 kubectl get pod --all-namespaces -o wide | grep lab3 kubectl get nodes -o wide 

启动node节点

# 加入master节点 # 这个命令是之前初始化master完成时，输出的命令 kubeadm join 11.11.11.110:6443 --token nevmjk.iuh214fc8i0k3iue --discovery-token-ca-cert-hash sha256:0e4f738348be836ff810bce754e059054845f44f01619a37b817eba83282d80f systemctl enable kubelet 

测试

重建多个coredns副本

# 删除coredns的pods kubectl get pods -n kube-system -o wide | grep coredns all_coredns_pods=$(kubectl get pods -n kube-system -o wide | grep coredns | awk '{print $1}' | xargs) echo $all_coredns_pods kubectl delete pods $all_coredns_pods -n kube-system # 修改副本数 # replicas: 3 # 可以修改为node节点的个数 kubectl edit deploy coredns -n kube-system # 查看状态 kubectl get pods -n kube-system -o wide | grep coredns 

基础测试

1. 启动

# 直接使用命令测试 kubectl run nginx --replicas=2 --image=nginx:alpine --port=80 kubectl expose deployment nginx --type=NodePort --name=example-service-nodeport kubectl expose deployment nginx --name=example-service # 使用配置文件测试 cat >example-nginx.yml<

kubectl get deploy kubectl get pods kubectl get svc kubectl describe svc example-service 

kubectl run curl --image=radial/busyboxplus:curl -i --tty nslookup kubernetes nslookup example-service curl example-service # 如果时间过长会返回错误，可以使用如下方式再进入测试 curlPod=$(kubectl get pod | grep curl | awk '{print $1}') kubectl exec -ti $curlPod -- sh 

# 10.96.59.56 为查看svc时获取到的clusterip curl "10.96.59.56:80" # 32223 为查看svc时获取到的 nodeport http://11.11.11.114:32223/ http://11.11.11.115:32223/ 

kubectl delete svc example-service example-service-nodeport kubectl delete deploy nginx curl 

kubectl get pod --all-namespaces -o wide kubectl get pod --all-namespaces -o wide | grep lab1 kubectl get pod --all-namespaces -o wide | grep lab2 kubectl get pod --all-namespaces -o wide | grep lab3 kubectl get nodes -o wide