使用k8s && minio 进行 postgres 数据库自动备份

 

通过k8s 的定时任务job，我们可以方便的进行定时任务应用的开发，通过minio s3 兼容的cloud native 存储
我们可以方便的通过http 请求进行数据文件的备份，以下简单演示下如何进行集成

环境准备

docker 镜像修改自 https://github.com/Remigius2011/pg-dump ,主要是去除了schema 同时添加了gzip 压缩处理

dockerfile

FROM remigius65/pg-dump
COPY backup.sh /usr/bin/backup.sh
RUN chmod +x /usr/bin/backup.sh

backup.sh

主要修改了dump 逻辑，说明备份使用了.pgpass 进行账户的处理，省去输入密码的问题，mc 客户端账户信息通过
环境变量处理

#!/bin/sh

. /usr/bin/setpwd.sh

export DUMP_FILE="$BACKUP_DIR/$DB_ENV-$(date +"%F-%H%M%S").dump"

if [ ! -d "$BACKUP_DIR" ]; then

  echo mkdir -p "$BACKUP_DIR"
  mkdir -p "$BACKUP_DIR"

fi

echo "pg_dump -h $PG_HOST -p $PG_PORT -U $PG_USER $PG_DB -f $DUMP_FILE"
pg_dump -h $PG_HOST -p $PG_PORT -U $PG_USER $PG_DB | gzip > $DUMP_FILE

if [ -n "S3_HOST" ]; then

  export MC_HOSTS_store="$S3_PROTOCOL://$S3_ACCESS_KEY:$S3_SECRET_KEY@$S3_HOST"
  echo "mc cp $DUMP_FILE store/$S3_BUCKET"
  mc cp $DUMP_FILE store/$S3_BUCKET

fi

docker-compose 文件

通过docker-compose 运行依赖的服务

version: "3"
services:
  postgres:
    image: postgres:10.7
    ports:
    - "5432:5432"
    environment:
    - "POSTGRES_PASSWORD:dalong"
    volumes:
    - ./db_data:/var/lib/postgresql/data
  backup:
    image: dalongrong/pg-dump
    environment:
    - "PG_HOST=postgres"
    - "PG_DB=postgres"
    - "PG_PASSWORD=dalong"
    - "S3_HOST=s3:9000"
    - "S3_ACCESS_KEY=dalongdemo"
    - "S3_SECRET_KEY=dalongdemo"
    - "S3_PROTOCOL=http"
  s3:
    image: minio/minio
    command: server /export
    ports:
    - "9000:9000"
    volumes:
      - ./data:/export
      - ./config:/root/.minio
    environment:
    - "MINIO_ACCESS_KEY=dalongdemo"
    - "MINIO_SECRET_KEY=dalongdemo"

测试

• 启动pg && minio

docker-compose up -d s3 postgres

• 添加以下测试数据
  这个可以根据自己的喜好，自由添加
• 测试数据备份

docker-compose up backup

• 测试效果

docker-compose up backup
Starting pg-s3-backup_backup_1 ... done
Attaching to pg-s3-backup_backup_1
backup_1 | pg_dump -h postgres -p 5432 -U postgres postgres -f /pgbackup/prod-2019-03-18-103712.dump
backup_1 | mc cp /pgbackup/prod-2019-03-18-103712.dump store/pgbackup
backup_1 | `/pgbackup/prod-2019-03-18-103712.dump` -> `store/pgbackup/prod-2019-03-18-103712.dump`
backup_1 | Total: 1.03 KB, Transferred: 1.03 KB, Speed: 33.52 KB/s
pg-s3-backup_backup_1 exited with code 0

• minio 界面
  

k8s cronjob

• json 格式文件

{
    "kind": "CronJob",
    "apiVersion": "batch/v1beta1",
    "metadata": {
      "name": "pg-backup-job"
    },
    "spec": {
      "schedule": "0 0 1 * *",
      "concurrencyPolicy": "Replace",
      "suspend": false,
      "jobTemplate": {
        "metadata": {
          "creationTimestamp": null
        },
        "spec": {
          "template": {
            "metadata": {
              "creationTimestamp": null,
              "labels": {
                "apprepositories.kubeapps.com/repo-name": "pg-backup-job"
              }
            },
            "spec": {
              "containers": [
                {
                  "name": "gitlab-pg-backup",
                  "image": "dalongrong/pg-dump-gzip",
                  "env": [
                    {
                        "name": "PG_DB",
                        "value": "postgres"
                    },
                    {
                        "name": "PG_HOST",
                        "value": "postgres"
                    },
                    {
                        "name": "PG_PASSWORD",
                        "value": "dalong"
                    },
                    {
                        "name": "PG_PORT",
                        "value": "5432"
                    },
                    {
                        "name": "S3_ACCESS_KEY",
                        "value": "dalongdemo"
                    },
                    {
                        "name": "S3_HOST",
                        "value": "s3:9000"
                    },
                    {
                        "name": "S3_PROTOCOL",
                        "value": "http"
                    },
                    {
                        "name": "S3_SECRET_KEY",
                        "value": "dalongdemo"
                    }
                ],
                  "imagePullPolicy": "IfNotPresent"
                }
              ],
              "restartPolicy": "OnFailure"
            }
          }
        }
      },
      "successfulJobsHistoryLimit": 3,
      "failedJobsHistoryLimit": 1
    }
  }

• yaml 格式

  yaml 格式因为是使用json-> yaml 的工具，格式很难看

kind: CronJob
apiVersion: batch/v1beta1
metadata:
    name: gitlab-backup-job
spec:
    schedule: "0 0 1 * *"
    concurrencyPolicy: Replace
    suspend: false
    jobTemplate:
        metadata:
            creationTimestamp: null
        spec:
            template:
                metadata:
                    creationTimestamp: null
                    labels:
                        apprepositories.kubeapps.com/repo-name: gitlab-backup-job
                spec:
                    containers:
                        - name: gitlab-pg-backup
                          image: dalongrong/pg-dump-gzip
                          env:
                              - name: PG_DB
                                value: postgres
                              - name: PG_HOST
                                value: postgres
                              - name: PG_PASSWORD
                                value: dalong
                              - name: PG_PORT
                                value: "5432"
                              - name: S3_ACCESS_KEY
                                value: dalongdemo
                              - name: S3_HOST
                                value: "s3:9000"
                              - name: S3_PROTOCOL
                                value: http
                              - name: S3_SECRET_KEY
                                value: dalongdemo
                          imagePullPolicy: IfNotPresent
                    restartPolicy: OnFailure
    successfulJobsHistoryLimit: 3
    failedJobsHistoryLimit: 1

• 运行效果

  因为k8s 定时备份的不是应用全部通过k8s 部署的，只有备份程序，pg 以及s3 都是外部的

容器日志

说明

结合k8s 的定时任务以及minio 的s3 能力，我们可以方便的制作一个备份以及恢复的方案，而且很简单

参考资料

https://github.com/Remigius2011/pg-dump
https://github.com/rongfengliang/pg-s3-backup
https://cloud.docker.com/repository/docker/dalongrong/pg-dump-gzip