一、使用CronJob定期备份MySQL¶
3.2.1 搭建MySQL¶
1、创建一个 MySQL 的 PVC
# 定义PVC
[root@k8s-master01 ~]# vim mysql-pvc.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mysql-data
spec:
accessModes:
- ReadWriteMany
resources:
requests:
storage: 10Gi
storageClassName: nfs-csi
# 创建PVC
[root@k8s-master01 ~]# kaf mysql-pvc.yaml
# 验证
[root@k8s-master01 ~]# kg pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS VOLUMEATTRIBUTESCLASS AGE
mysql-data Bound pvc-1c159b41-7afd-467f-a8b9-ecfdf9089ef5 10Gi RWX nfs-csi <unset> 2s
2、创建一个 MySQL 的 Deployment
[root@k8s-master01 ~]# vim deployment-mysql.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app: mysql
name: mysql
spec:
replicas: 1
selector:
matchLabels:
app: mysql
strategy:
type: Recreate # 单实例策略，适合有状态应用
template:
metadata:
labels:
app: mysql # 必须与selector.matchLabels一致
spec:
containers:
- name: mysql
image: registry.cn-hangzhou.aliyuncs.com/abroad_images/mysql:8.0.20
ports:
- containerPort: 3306 # 暴露MySQL默认端口
protocol: TCP
env:
- name: MYSQL_ROOT_PASSWORD # 建议生产环境改用Secret
value: "123456" # 示例密码，实际需加密
volumeMounts:
- name: data
mountPath: /var/lib/mysql # MySQL数据持久化目录
livenessProbe: # 存活探针
tcpSocket:
port: 3306
initialDelaySeconds: 30 # 容器启动30秒后开始探测
timeoutSeconds: 3 # 探测超时时间
periodSeconds: 30 # 每30秒探测一次
successThreshold: 1
failureThreshold: 2 # 连续失败2次标记为不健康
readinessProbe: # 就绪探针（配置同存活探针）
tcpSocket:
port: 3306
initialDelaySeconds: 30
timeoutSeconds: 3
periodSeconds: 30
successThreshold: 1
failureThreshold: 2
volumes: # 卷定义（与containers同级）
- name: data
persistentVolumeClaim:
claimName: mysql-data # 关联的PVC名称
dnsPolicy: ClusterFirst # DNS解析策略（默认值）
3、创建MySQL,并查看启动状态
[root@k8s-master01 ~]# kaf deployment-mysql.yaml
# 验证
[root@k8s-master01 ~]# kgp
NAME READY STATUS RESTARTS AGE
mysql-676759b6c-g9jj7 1/1 Running 0 53s
4、MySQL 启动后，会在数据目录初始化基础数据，此时可以在后端存储中看到
[root@k8s-node02 ~]# ls /data/nfs/pvc-1c159b41-7afd-467f-a8b9-ecfdf9089ef5
auto.cnf client-cert.pem ib_logfile0 performance_schema undo_001
binlog.000001 client-key.pem ib_logfile1 private_key.pem undo_002
binlog.000002 '#ib_16384_0.dblwr' ibtmp1 public_key.pem
binlog.index '#ib_16384_1.dblwr' '#innodb_temp' server-cert.pem
ca-key.pem ib_buffer_pool mysql server-key.pem
ca.pem ibdata1 mysql.ibd sys
5、创建一个 MySQL 的 Service
[root@k8s-master01 ~]# k expose deploy mysql --port 3306
3.2.2 MySQL手工备份测试¶
1、创建测试数据，用于备份
[root@k8s-master01 ~]# kgp
NAME READY STATUS RESTARTS AGE
mysql-676759b6c-g9jj7 1/1 Running 0 53s
# 进入数据库创建测试数据表
[root@k8s-master01 ~]# k exec -it mysql-676759b6c-g9jj7 -- bash
root@mysql-676759b6c-vzrgn:/# mysql -uroot -p123456
mysql> create database zq;
mysql> use zq;
mysql> CREATE TABLE test (
id INT AUTO_INCREMENT PRIMARY KEY,
f_name VARCHAR(10),
l_name VARCHAR(20)
);
mysql> show tables;
+--------------+
| Tables_in_zq |
+--------------+
| test |
+--------------+
1 row in set (0.00 sec)
2、手工备份进行测试
[root@k8s-master01 ~]# k exec -it mysql-676759b6c-g9jj7 -- bash
root@mysql-676759b6c-vzrgn:/# mysqldump -uroot -p'123456' -A > /tmp/all.sql;
root@mysql-676759b6c-vzrgn:/# ls /tmp/all.sql
/tmp/all.sql
3.2.3 创建Cronjob备份Mysql¶
1、创建一个用于放置 CronJob 的命名空间
[root@k8s-master01 ~]# k create ns cronjob
2、创建一个备份MySQL 的 PVC
# 定义PVC
[root@k8s-master01 ~]# vim mysql-backup-pvc.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mysql-backup-data
namespace: cronjob
spec:
accessModes:
- ReadWriteMany
resources:
requests:
storage: 10Gi
storageClassName: nfs-csi
# 创建PVC
[root@k8s-master01 ~]# kaf mysql-backup-pvc.yaml
# 验证
[root@k8s-master01 ~]# kg pvc -n cronjob
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS VOLUMEATTRIBUTESCLASS AGE
mysql-backup-data Bound pvc-9a631121-b284-4ea9-b476-9aa15f6532b0 10Gi RWX nfs-csi <unset> 8s
3、定义Cronjob的yaml文件
[root@k8s-master01 ~]# vim mysql-backup.yaml
apiVersion: batch/v1
kind: CronJob
metadata:
name: mysql-backup
namespace: cronjob
spec:
schedule: "00 01 * * *" # 每天凌晨1点执行（UTC时间）
timeZone: Asia/Shanghai # 需 Kubernetes 1.25+ 版本支持
successfulJobsHistoryLimit: 5 # 保留成功Job记录数
failedJobsHistoryLimit: 5 # 保留失败Job记录数
jobTemplate:
spec:
template:
spec:
containers:
- name: backup
image: registry.cn-hangzhou.aliyuncs.com/abroad_images/mysql:8.0.20
command:
- sh
- -c
- |
mysqldump -hmysql.default -P3306 -uroot -p'123456' -A > /mnt/all-$(date +%Y%m%d-%H%M%S).sql
ls -l /mnt
volumeMounts:
- name: backup-data
mountPath: /mnt
restartPolicy: Never # 必须为 Never 或 OnFailure
volumes:
- name: backup-data
persistentVolumeClaim:
claimName: mysql-backup-data
2、创建Cronjob
[root@k8s-master01 ~]# kaf mysql-backup.yaml
3、查看创建情况
[root@k8s-master01 ~]# kg cj -n cronjob
NAME SCHEDULE TIMEZONE SUSPEND ACTIVE LAST SCHEDULE AGE
mysql-backup 00 01 * * * Asia/Shanghai False 0 <none> 93s
4、因为这里是凌晨1点才会触发定时任务，这里手工模拟触发定时任务
[root@k8s-master01 ~]# k create job mysql-backup-test --from=cronjob.batch/mysql-backup -n cronjob
5、查看资源创建情况
# 查看job创建情况
[root@k8s-master01 ~]# kg job -n cronjob
NAME STATUS COMPLETIONS DURATION AGE
mysql-backup-test Complete 1/1 7s 19
# 查看pod创建情况
[root@k8s-master01 ~]# kgp -n cronjob
NAME READY STATUS RESTARTS AGE
mysql-backup-test-mfh9j 0/1 Completed 0 25s
# 查看备份记录
[root@k8s-master01 ~]# k logs -f mysql-backup-test-mfh9j -n cronjob
mysqldump: [Warning] Using a password on the command line interface can be insecure.
total 4032
-rw-r--r-- 1 root root 3720615 Mar 21 10:52 all-20250321-105223.sq
# 查看备份位置
[root@k8s-node02 ~]# ls /data/nfs/pvc-9a631121-b284-4ea9-b476-9aa15f6532b0
all-20250321-105223.sql
6、环境复原
kubectl delete -f deployment-mysql.yaml -f mysql-backup.yaml -f mysql-backup-pvc.yaml -f mysql-pvc.yaml