PostgreSQL备份恢复

一、PostgreSQL备份方案

  一)PostgreSQL两种备份方案

  • 方案一:逻辑备份——使用pg_dump
  • 方案二:物理备份——使用pg_rman

二、PostgreSQL逻辑备份恢复

  一)逻辑备份:pg_dump

  1、pg_dump简介

  pg_dump 支持备份表,备份用户,备份数据库

  pg_dumpall 支持导出全库的数据

  pg_dump 可以把数据备份成SQL文本的形式,也可以自定义为tar包等二进制

  2、备份数据操作

  常用备份命令(查看帮助信息)

pg_dump --help

 

  备份实操

# 备份准备
mkdir -p /pgbak
chown postgres.postgres /pgbak

#本机备份
## 方式一:使用重定向符号
pg_dump db_name > /pgbak/db_name.sql

## 方式二:使用pg参数
pg_dump db_name --file=/pgbak/db_name1.sql


# 远程备份,备份文件存放到远程主机上
pg_dump --username=postgres --host=host_ip --port=5432 --format=tar --file=/data/backup/pgbak/db_name.tar


# 压缩备份
若遇到数据库容量比较大时,可以选择压缩备份
pg_dump --dbname=db_name --format=custom --file=/pgbak/db_bame.dump

 

  二)恢复

  1、恢复方式

  psql恢复:一般恢复SQL文本

  pg_restore恢复:一般恢复压缩的二进制文件

  2、恢复实现

# 基于sql文件恢复
pgsql --dbname=db_name --file=db_name.sql

# 基于dump压缩文件恢复
pg_restore --dbname=db_name db_name.dump

 

三、PostgreSQL物理备份恢复

  一)物理备份:pg_rman

  1、pg_rman 简介

   pg_rman是一款专门为postgresql设计的在线备份恢复的工具。其支持在线和基于时间点备份方式,还可以通过创建backup catalog来维护DB cluster备份信息。

    pg_rman的特点
  • 使用简单.一个命令即可完成备份和恢复.
  • 支持在线全备,增量备份,归档备份.
  • 支持备份压缩.通过gzip工具实现页内压缩.
  • 自动备份维护.自动删除过期的WAL备份文件.
  • 支持备份验证.
  • 恢复期间无事务丢失.支持基于PITR的配置文件生成器
    pg_rman 注意事项:
  • pg_rman 基于 pg_start_backup
  • pg_rman 基于 需要在本地安装,不能远程德份
  • pg_rman 需要下载对应的版本

  2、pg_rman安装

    pg_rman下载
下载地址:
https://github.com/ossc-db/pg_rman/

PostgreSQL Rpm相关依赖、插件包下载地址:
https://yum.postgresql.org/10/redhat/rhel-6.7-x86_64/

手册地址:
http://ossc-db.github.io/pg_rman/index.html
    pg_rman安装、配置
源码包安装方法:
  1、下载源码包
         wget  https://github.com/ossc-db/pg_rman/releases/download/V1.3.7/pg_rman-1.3.7-pg10.tar.gz    
   2、解压到指定目录
         tar -zxvf  pg_rman-1.3.14-pg12.tar.gz -C opt/
   3、进入到rman目录进行编译安装
         cd opt/pg_rman-1.3.14-pg12/
         make && make install

  设置环境变量:/etc/profile 或/etc/bashrc

# 设置环境变量:
PATH=$PATH:$HOME/bin
export PG_RMAN=/u01/postgresql/pg12
export PGHOME=/u01/postgresql/pg12
export PGDATA=/u01/postgresql/data
export PGLIB=/u01/postgresql/pg12/lib
export SRVLOG_PATH=/u01/postgresql/data/log
export ARCLOG_PATH=/u01/postgresql/archive
export BACKUP_PATH=/opt/pg_rman
export PATH=$PGHOME/bin:$PATH:$PG_RMAN/bin
export PATH

  使设置的环境变量生效

source /etc/profile

 

  3、pg_rman的用法

pg_rman的使用相对简单核心8个命令

pg_rman manage backup/recovery of PostgreSQL database.

Usage:
  pg_rman OPTION init
  pg_rman OPTION backup
  pg_rman OPTION restore
  pg_rman OPTION show [DATE]
  pg_rman OPTION show detail [DATE]
  pg_rman OPTION validate [DATE]
  pg_rman OPTION delete DATE
  pg_rman OPTION purge
init      初始化备份目录
backup    在线备份
restore   恢复
show      查看备份历史
validate  验证备份
delete    删除备份文件
purge     从备份目录中删除已删除备份

 

  4、备份

    初始化备份目录
先需要初始化一个backup catalog,目录将用于存放备份的文件,目录也会存放一些元数据,例如备份的配置文件,数据库的systemid,时间线文件历史   
注意:在初始化的时候,要先确认环境变量是否设置正确。
# pg_rman init -B opt/pg_rman

总用量 8
drwx------ 4 root root 35 11月 23 13:30 backup
-rw-r--r-- 1 root root 83 11月 23 13:30 pg_rman.ini
-rw-r--r-- 1 root root 40 11月 23 13:30 system_identifier
drwx------ 2 root root  6 11月 23 13:30 timeline_history

  

    查看pg_rman的备份配置文件
$ cat pg_rman.ini 
ARCLOG_PATH=‘/home/postgres/arch’                        --归档目录
SRVLOG_PATH=‘/home/postgres/data/log’                   --数据库错误日志目录
COMPRESS_DATA = YES                                   --压缩数据
KEEP_ARCLOG_FILES = 10                                 --保存归档文件个数
KEEP_ARCLOG_DAYS = 10                                  --保存归档的天数
KEEP_DATA_GENERATIONS = 3                               --备份冗余度
KEEP_DATA_DAYS = 10                                   --保存备份集时间
KEEP_SRVLOG_FILES = 10                                 --保存日志文件个数
KEEP_SRVLOG_DAYS = 10                                  --保存日志文件天数

 

    pg_rman的全量备份
如果没有调设置export BACKUP_PATH=/opt/pg_rman ,需要手动指明备份路径 --backup-path=/opt/pg_rman

postgres@s2ahumysqlpg01-> pg_rman backup --backup-mode=full --with-serverlog -h 127.0.0.1
INFO:cyidbfi INFO:cyichivdWALfi INFO:cyivfi INFO:bckuc INFO:Pcu
'vid'vifyhficcycid. 一、pg_rman 校验备份集:

postgres@s2ahumysqlpg01-> pg_rman show
=====================================================================
StartTime EndTime Mode Size TLI Status
=====================================================================
2022-02-22 17:18:39 2022-02-22 17:19:12 FULL 942MB 5 DONE

二、未校验备份集 Status 显示为 DONE,开始校验

[postgres@mxl pg_rman]$ pg_rman validate
INFO: validate: "2019-12-03 11:53:39" backup, archive log files and server log files by CRC
INFO: backup "2019-12-03 11:53:39" is valid
[postgres@mxl pg_rman]$ pg_rman show

=====================================================================
StartTime EndTime Mode Size TLI Status
=====================================================================
2019-12-03 11:53:39 2018-12-03 11:54:00 FULL 461MB 1 OK

三、删除备份集
# pg_rman 删除只是逻辑删除,备份文件还存在;删除语法:pg_rman delete 备份的结束时间
pg_rman delete
2022-02-22 17:19:12
# pg_rman 删除备份文件;删除语法:pg_rman purge
pg_rman purge

    增量备份
增量备份是基于文件系统的update time时间线,增量备份必须有个对应的全库备份
postgres@s2ahumysqlpg01-> pg_rman backup --backup-mode=incremental --progress --compress-data  -h 127.0.0.1
INFO: copying database files
INFO: copying archived WAL filesipped 3028
Processed 16 of 16 files, skipped 13
INFO: backup complete

INFO: Please execute 'pg_rman validate' to verify the files are correctly copied.

备份集查看:

$ pg_rman show
    postgres@s2ahumysqlpg01-> pg_rman show
=====================================================================
 StartTime           EndTime              Mode    Size   TLI  Status 
=====================================================================
2022-02-22 17:22:54  2022-02-22 17:22:58  INCR    33kB     5  DONE
2022-02-22 17:18:39  2022-02-22 17:19:12  FULL   942MB     5  OK

# 校验 postgres@s2ahumysqlpg01
-> pg_rman validate INFO: validate: "2022-02-22 17:22:54" backup and archive log files by CRC INFO: backup "2022-02-22 17:22:54" is valid

# 查看备份集 postgres@s2ahumysqlpg01
-> pg_rman show ===================================================================== StartTime EndTime Mode Size TLI Status ===================================================================== 2022-02-22 17:22:54 2022-02-22 17:22:58 INCR 33kB 5 OK 2022-02-22 17:18:39 2022-02-22 17:19:12 FULL 942MB 5 OK

 

    pg_rman 归档备份
一、pg_rman 归档备份:
归档备份就是静态文件的拷贝。

$ pg_rman backup --backup-mode=archive --progress --compress-data 
$ pg_rman validate
$ pg_rman show

二、删除备份集
删除备份集指定日期之前的,不需要用来指定时间点之前的备份删除掉
$ pg_rman delete " pg_rman delete "2022-02-22 17:22:58""

三、清除备份集
物理删除已从catalog删除的备份集
上面从备份集中删除的备份,备份集文件夹并没有一起删除。
$ pg_rman purge

  二)恢复

  1、数据恢复步骤

  • 停止数据库:pg_ctl stop
  • 恢复数据:
    • 全量恢复:pg_rman restore
    • 增量恢复(基于时间点恢复):pg_rman restore --recovery-targe-time="2022-02-22 17:22:58"
  • 启动数据库:pg_ctl start

  

  2、数据恢复操作方法

pg_rman 恢复默认原地恢复(覆盖式),或者使用新的$PGDATA作为恢复目标。需注意如果在本机恢复pg_rman可能会覆盖原有的数据文件arch,pg_xlog目录中的文件, 可以先将原数据文件做下备份,默认pg_rman restore会在$PGDATA下产生recovery.conf根据实际需要修改相关恢复参数即可。

1、recovery-target-timeline TIMELINE  
Specifies recovering into a particular timeline. If not specified, the current timeline from ($PGDATA
/global/pg_control) is used. 如果不指定时间线,则使用$PGDATA/global/pg_control,如果没有$PGDATA/global/pg_control,则使用最新的全量备份集的时间线。 2、recovery-target-time TIMESTAMP
This parameter specifies the
time stamp up to which recovery will proceed. If not specified, continue recovery to the latest time. 如果不指定,则恢复到最新时间 3、recovery-target-xid XID
This parameter specifies the transaction ID up to
which recovery will proceed. If not specified, continue recovery to the latest xid. 如果不指定,则恢复到最新xid 4、recovery-target-inclusive Specifies whether we stop just after the specified recovery target (true), or just before the recovery target (false). Default is true. 是否在指定的恢复目标(true)之后停止,默认为true,如果指定false意识是在恢复目标之前停止 • The following parameter determines the behavior of restore. --hard-copy The archive WAL are copied to archive WAL storage area. If not specified, pg_rman makes symbolic link to archive WAL where are in the backup catalog directory. 是否使用硬链接复制archive log,如果不指定使用符号连接(软连接)的方式。 #示例: #pg_rman restore --recovery-target-time "2022-02-22 17:25:30"; 下面是没有指定的恢复 [postgres@mxl~]$ pg_rman restore INFO: backup "2022-02-22 17:25:30" is valid INFO: the recovery target timeline ID is not given INFO: use timeline ID of current database cluster as recovery target: 5 INFO: calculating timeline branches to be used to recovery target point INFO: searching latest full backup which can be used as restore start point INFO: found the full backup can be used as base in recovery: "2022-02-22 17:25:30" INFO: copying online WAL files and server log files INFO: clearing restore destination INFO: validate: "2022-02-22 17:25:30" backup, archive log files and server log files by SIZE INFO: backup "2022-02-22 17:25:30" is valid INFO: restoring database files from the full mode backup "2022-02-22 17:25:30" INFO: searching incremental backup to be restored INFO: searching backup which contained archived WAL files to be restored INFO: backup "2022-02-22 17:25:30" is valid INFO: restoring WAL files from backup "2022-02-22 17:25:30" INFO: restoring online WAL files and server log files INFO: create pg_rman_recovery.conf for recovery-related parameters. INFO: remove an 'include' directive added by pg_rman in postgresql.conf if exists INFO: append an 'include' directive in postgresql.conf for pg_rman_recovery.conf INFO: generating recovery.signal INFO: removing standby.signal if exists to restore as primary INFO: restore complete HINT: Recovery will start automatically when the PostgreSQL server is started. After the recovery is done, we recommend to remove recovery-related parameters configured by pg_rman. pg_ctl start

 

posted @ 2023-01-17 20:38  思维无界限  阅读(668)  评论(0编辑  收藏  举报