PG-pg_rman物理备份工具

g_rman 物理备份

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

下载地址

软件安装

wget https://github.com/ossc-db/pg_rman/releases/download/V1.3.13/pg_rman-1.3.13-pg12.tar.gz 

tar -xf pg_rman-1.3.13-pg12.tar.gz
cd pg_rman-1.3.13-pg12
yum -y install zlib-devel
make
make install

pg_rman的用法(pg_rman --help)

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

Common Options:
  -D, --pgdata=PATH         location of the database storage area
  -A, --arclog-path=PATH    location of archive WAL storage area
  -S, --srvlog-path=PATH    location of server log storage area
  -B, --backup-path=PATH    location of the backup storage area
  -c, --check               show what would have been done
  -v, --verbose             show what detail messages
  -P, --progress            show progress of processed files

Backup options:
  -b, --backup-mode=MODE    full, incremental, or archive
  -s, --with-serverlog      also backup server log files
  -Z, --compress-data       compress data backup with zlib
  -C, --smooth-checkpoint   do smooth checkpoint before backup
  -F, --full-backup-on-error   switch to full backup mode
                               if pg_rman cannot find validate full backup
                               on current timeline
      NOTE: this option is only used in --backup-mode=incremental or archive.
  --keep-data-generations=NUM keep NUM generations of full data backup
  --keep-data-days=NUM        keep enough data backup to recover to N days ago
  --keep-arclog-files=NUM   keep NUM of archived WAL
  --keep-arclog-days=DAY    keep archived WAL modified in DAY days
  --keep-srvlog-files=NUM   keep NUM of serverlogs
  --keep-srvlog-days=DAY    keep serverlog modified in DAY days
  --standby-host=HOSTNAME   standby host when taking backup from standby
  --standby-port=PORT       standby port when taking backup from standby

Restore options:
  --recovery-target-time    time stamp up to which recovery will proceed
  --recovery-target-xid     transaction ID up to which recovery will proceed
  --recovery-target-inclusive whether we stop just after the recovery target
  --recovery-target-timeline  recovering into a particular timeline
  --hard-copy                 copying archivelog not symbolic link

Catalog options:
  -a, --show-all            show deleted backup too

Delete options:
  -f, --force               forcibly delete backup older than given DATE

Connection options:
  -d, --dbname=DBNAME       database to connect
  -h, --host=HOSTNAME       database server host or socket directory
  -p, --port=PORT           database server port
  -U, --username=USERNAME   user name to connect as
  -w, --no-password         never prompt for password
  -W, --password            force password prompt

Generic options:
  -q, --quiet               don't show any INFO or DEBUG messages
  --debug                   show DEBUG messages
  --help                    show this help, then exit
  --version                 output version information, then exit

备份操作

全量备份

[postgres@progs pg_rman]$ pg_rman backup --backup-mode=full --backup-path=/ups/data/pgdata/12/backups/pg_rman
INFO: copying database files
INFO: copying archived WAL files
INFO: backup complete
INFO: Please execute 'pg_rman validate' to verify the files are correctly copied.
[postgres@progs pg_rman]$

增量备份

pg_rman backup --backup-mode=incremental --backup-path=/ups/data/pgdata/12/backups/pg_rman

备份集校验

# 每次备份完，必须要做一次校验，否则备份集不可用用来恢复，增量备份时也不会用它来做增量比较
export BACKUP_PATH='/ups/data/pgdata/12/backups/pg_rman' && pg_rman validate
pg_rman validate --backup-path=/ups/data/pgdata/12/backups/pg_rman

查看备份集

pg_rman show

删除备份集

删除指定时间的备份集

# 从catalog删除指定时间的备份集
## 例如：只需要能恢复到2021-09-23 11:00:00，在这个时间点以前的不需要用来恢复到这个时间点的备份全删掉
pg_rman delete '2021-09-23 11:00:00'

根据备份策略来删除备份集

# 在备份时，指定备份策略
pg_rman backup --backup-mode=incremental --keep-data-generations=2 --keep-data-days=10 --keep-data-generations=2 

清除备份集

它不是删除备份集中物理文件，仅删除catalog中的备份条目

pg_rman purge

恢复操作

恢复操作选项

Restore options:
  --recovery-target-time    time stamp up to which recovery will proceed
  --recovery-target-xid     transaction ID up to which recovery will proceed
  --recovery-target-inclusive whether we stop just after the recovery target
  --recovery-target-timeline  recovering into a particular timeline
  --recovery-target-action    action the server should take once the recovery target is reached
  --hard-copy                 copying archivelog not symbolic link

使用最新全备恢复到$PGDATA目录

[postgres@progs pg_rman]$ export PGDATA=/tmp/pg_recov
[postgres@progs pg_rman]$ pg_rman restore