环境介绍
名称 | 版本 | 操作系统 | IP | 备注 |
---|---|---|---|---|
K8S集群 | 1.20.15 | Centos7.9 | 192.168.11.21 192.168.11.22 192.168.11.23 | 21为k8s-master 22为k8s-node01 23为k8s-node02 |
MySql | 5.7 | Centos7.9 | 一主两从 | |
nfs服务器 | Centos7.9 | 192.168.11.24 | 共享目录为/nfs |
一、部署NFS服务器
11.24:
1.创建NFS共享目录
mkdir -p /nfs
2.安装NFS服务
yum -y install nfs-utils rpcbind
3.编辑NFS配置
echo "/nfs *(rw,async,no_root_squash)" >>/etc/exports
4.启动服务
systemctl enable --now nfs-server systemctl enable --now rpcbind
5.验证
showmount -e ##看是否能看到/nfs *字段;如果没有该命令yum -y install showmount
11.21/22/23(所有K8S节点):
1.安装NFS
yum -y install nfs-utils
2.测试是否能检测到NFS共享目录
showmount -e 192.168.11.24 ##看是否能看到/nfs *
二、创建PV
11.21:
1、创建存放MySQL的yaml清单目录
mkdir -p /webapp cd /webapp
2、创建NFS的YAML文件
vim nfs-client.yaml
apiVersion: apps/v1 kind: Deployment metadata: name: nfs-client-provisioner labels: app: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default spec: replicas: 1 strategy: type: Recreate selector: matchLabels: app: nfs-client-provisioner template: metadata: labels: app: nfs-client-provisioner spec: serviceAccountName: nfs-client-provisioner containers: - name: nfs-client-provisioner image: registry.cn-beijing.aliyuncs.com/xngczl/nfs-subdir-external-provisione:v4.0.0 volumeMounts: - name: nfs-client-root mountPath: /persistentvolumes env: - name: PROVISIONER_NAME value: fuseim.pri/ifs #注意这个值,可以自定义 - name: NFS_SERVER value: 192.168.11.24 ##IP不同修改此处 - name: NFS_PATH value: /nfs ##nfs共享目录 volumes: - name: nfs-client-root nfs: server: 192.168.11.24 ##IP不同修改此处 path: /nfs ##nfs共享目录
创建rbac
vim nfs-client-rbac.yaml
apiVersion: v1 kind: ServiceAccount metadata: name: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default --- kind: ClusterRole apiVersion: rbac.authorization.k8s.io/v1 metadata: name: nfs-client-provisioner-runner rules: - apiGroups: [""] resources: ["nodes"] verbs: ["get", "list", "watch"] - apiGroups: [""] resources: ["persistentvolumes"] verbs: ["get", "list", "watch", "create", "delete"] - apiGroups: [""] resources: ["persistentvolumeclaims"] verbs: ["get", "list", "watch", "update"] - apiGroups: ["storage.k8s.io"] resources: ["storageclasses"] verbs: ["get", "list", "watch"] - apiGroups: [""] resources: ["events"] verbs: ["create", "update", "patch"] --- kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: run-nfs-client-provisioner subjects: - kind: ServiceAccount name: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default roleRef: kind: ClusterRole name: nfs-client-provisioner-runner apiGroup: rbac.authorization.k8s.io --- kind: Role apiVersion: rbac.authorization.k8s.io/v1 metadata: name: leader-locking-nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default rules: - apiGroups: [""] resources: ["endpoints"] verbs: ["get", "list", "watch", "create", "update", "patch"] --- kind: RoleBinding apiVersion: rbac.authorization.k8s.io/v1 metadata: name: leader-locking-nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default subjects: - kind: ServiceAccount name: nfs-client-provisioner # replace with namespace where provisioner is deployed namespace: default roleRef: kind: Role name: leader-locking-nfs-client-provisioner apiGroup: rbac.authorization.k8s.io
创建sc
vim nfs-client-class.yaml
apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: course-nfs-storage
启动:
kubectl apply -f nfs-client.yaml kubectl apply -f nfs-client-rbac.yaml kubectl apply -f nfs-client-class.yaml kubectl get po,sc NAME READY STATUS RESTARTS AGE pod/nfs-client-provisioner-8579c9d69b-m6vp4 1/1 Running 0 13m NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE storageclass.storage.k8s.io/course-nfs-storage fuseim.pri/ifs Delete Immediate false 13m
三、编写MySQL的yaml文件
11.21:
mkdir -p /weapp/mysql cd /weapp/mysql
创建CM
```bash
vim mysql-configmap.yaml
apiVersion: v1 kind: ConfigMap metadata: name: mysql labels: app: mysql data: master.cnf: | # Apply this config only on the master. [mysqld] log-bin slave.cnf: | # Apply this config only on slaves. [mysqld] super-read-only
此文件定义了两个MySQL的配置文件
1.是master.cnf,开启了log-bin。开启二进制日志文件后才能进行主从复制
2.slave.cnf,开启了super-read-only,表示从节点只能读,不能进行其他操作。
两个文件以配置文件形式挂载到mysql容器中`
创建MySQL的Service
vim mysql-services.yaml
apiVersion: v1 kind: Service metadata: name: mysql labels: app: mysql spec: ports: - name: mysql port: 3306 clusterIP: None selector: app: mysql --- # Client service for connecting to any MySQL instance for reads. # For writes, you must instead connect to the master: mysql-0.mysql. apiVersion: v1 kind: Service metadata: name: mysql-read labels: app: mysql spec: ports: - name: mysql port: 3306 selector: app: mysql
创MySQL的StatefulSet
vim mysql-statefulset.yaml
apiVersion: apps/v1 kind: StatefulSet metadata: name: mysql spec: selector: matchLabels: app: mysql serviceName: mysql replicas: 3 template: metadata: labels: app: mysql spec: initContainers: - name: init-mysql image: mysql:5.7 command: - bash - "-c" - | set -ex # Generate mysql server-id from pod ordinal index. [[ `hostname` =~ -([0-9]+)$ ]] || exit 1 ordinal=${BASH_REMATCH[1]} echo [mysqld] > /mnt/conf.d/server-id.cnf # Add an offset to avoid reserved server-id=0 value. echo server-id=$((100 + $ordinal)) >> /mnt/conf.d/server-id.cnf # Copy appropriate conf.d files from config-map to emptyDir. if [[ $ordinal -eq 0 ]]; then cp /mnt/config-map/master.cnf /mnt/conf.d/ else cp /mnt/config-map/slave.cnf /mnt/conf.d/ fi volumeMounts: - name: conf mountPath: /mnt/conf.d - name: config-map mountPath: /mnt/config-map - name: clone-mysql image: fxkjnj/xtrabackup:1.0 command: - bash - "-c" - | set -ex # Skip the clone if data already exists. [[ -d /var/lib/mysql/mysql ]] && exit 0 # Skip the clone on master (ordinal index 0). [[ `hostname` =~ -([0-9]+)$ ]] || exit 1 ordinal=${BASH_REMATCH[1]} [[ $ordinal -eq 0 ]] && exit 0 # Clone data from previous peer. ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql # Prepare the backup. xtrabackup --prepare --target-dir=/var/lib/mysql volumeMounts: - name: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d containers: - name: mysql image: mysql:5.7 env: - name: MYSQL_ALLOW_EMPTY_PASSWORD value: "1" ports: - name: mysql containerPort: 3306 volumeMounts: - name: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d resources: requests: cpu: 500m memory: 1Gi livenessProbe: exec: command: ["mysqladmin", "ping"] initialDelaySeconds: 30 periodSeconds: 10 timeoutSeconds: 5 readinessProbe: exec: # Check we can execute queries over TCP (skip-networking is off). command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"] initialDelaySeconds: 5 periodSeconds: 2 timeoutSeconds: 1 - name: xtrabackup image: fxkjnj/xtrabackup:1.0 ports: - name: xtrabackup containerPort: 3307 command: - bash - "-c" - | set -ex cd /var/lib/mysql # Determine binlog position of cloned data, if any. if [[ -f xtrabackup_slave_info && "x$(<xtrabackup_slave_info)" != "x" ]]; then # XtraBackup already generated a partial "CHANGE MASTER TO" query # because we're cloning from an existing slave. (Need to remove the tailing semicolon!) cat xtrabackup_slave_info | sed -E 's/;$//g' > change_master_to.sql.in # Ignore xtrabackup_binlog_info in this case (it's useless). rm -f xtrabackup_slave_info xtrabackup_binlog_info elif [[ -f xtrabackup_binlog_info ]]; then # We're cloning directly from master. Parse binlog position. [[ `cat xtrabackup_binlog_info` =~ ^(.*?)[[:space:]]+(.*?)$ ]] || exit 1 rm -f xtrabackup_binlog_info xtrabackup_slave_info echo "CHANGE MASTER TO MASTER_LOG_FILE='${BASH_REMATCH[1]}',\ MASTER_LOG_POS=${BASH_REMATCH[2]}" > change_master_to.sql.in fi # Check if we need to complete a clone by starting replication. if [[ -f change_master_to.sql.in ]]; then echo "Waiting for mysqld to be ready (accepting connections)" until mysql -h 127.0.0.1 -e "SELECT 1"; do sleep 1; done echo "Initializing replication from clone position" mysql -h 127.0.0.1 \ -e "$(<change_master_to.sql.in), \ MASTER_HOST='mysql-0.mysql', \ MASTER_USER='root', \ MASTER_PASSWORD='', \ MASTER_CONNECT_RETRY=10; \ START SLAVE;" || exit 1 # In case of container restart, attempt this at-most-once. mv change_master_to.sql.in change_master_to.sql.orig fi # Start a server to send backups when requested by peers. exec ncat --listen --keep-open --send-only --max-conns=1 3307 -c \ "xtrabackup --backup --slave-info --stream=xbstream --host=127.0.0.1 --user=root" volumeMounts: - name: data mountPath: /var/lib/mysql subPath: mysql - name: conf mountPath: /etc/mysql/conf.d resources: requests: cpu: 100m memory: 100Mi volumes: - name: conf emptyDir: {} - name: config-map configMap: name: mysql volumeClaimTemplates: - metadata: name: data spec: storageClassName: "course-nfs-storage" accessModes: ["ReadWriteOnce"] resources: requests: storage: 0.5Gi
- 使用xtrbackup工具进行初始化数据的备份
- 使用linux自带的ncat工具进行容器初始化数据拷贝
- 使用mysql的bin-log实现主从复制
- 使用mysqladmin的ping作为健康检查方式
- 利用pod的主机名的序号来判定当前节点为主还是从,再根据节点拷贝不同的配置文件到指定目录
四、启动MySQL
11.21
kubectl apply -f mysql-configmap.yaml kubectl apply -f mysql-services.yaml kubectl apply -f mysql-statefulset.yaml kubectl get po NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES mysql-0 2/2 Running 0 3h12m 10.244.0.5 k8s-master1 <none> <none> mysql-1 2/2 Running 0 3h11m 10.244.1.6 k8s-node02 <none> <none> mysql-2 2/2 Running 0 3h10m 10.244.1.5 k8s-node01 <none> <none>
五、验证MySQL主从复制
11.21:
kubectl exec -it mysql-0 -- bash ##进入mysqk-0pod mysql -h mysql-0.mysql ##进入数据库 CREATE DATABASE test; ##创建库表。 CREATE TABLE test.messages (message VARCHAR(250)); INSERT INTO test.messages VALUES ('hello'); \q exit kubectl exec -it mysql-1 -- bash ##进入mysql-1pod mysql -h mysql-1.mysql ##进入数据库 SELECT * FROM test.messages; ##看是否看得到创建的test库
获得以下输出
Waiting for pod default/mysql-client to be running, status is Pending, pod ready: false
+---------+
| message |
+---------+
| hello |
+---------+