一、工具介绍
pgBackRest是PostgreSQL数据库的一个开源备份工具，支持全量、增量和差异备份。这一点优于PG原生的备份工具pg_basebackup，因为pg_basebackup不支持增量备份，并且支持备份完整性检查等等。pgBackRest v2.49是当前的稳定版本。
项目主页：https://pgbackrest.org/
Github链接：https://github.com/pgbackrest/pgbackrest
优点：
支持本地或远程操作， 但是远程操作需要配置SSH
支持全量、增量和差异备份
支持从standby实例备份，减小主库的IO压力
支持备份完整性检查（checksum 算法）
支持压缩：支持gzip, bzip, lz4, zstd等压缩算法，并提供不同压缩等级
二、部署pgBackRest备份工具
1.安装依赖
yum -y install libxml2 libxml2-devel libyaml libyaml-devel bzip2 bzip2-devel
2.创建所需目录并赋予权限
su - root
mkdir -p -m 770 /var/log/pgbackrest
chown postgres.postgres /var/log/pgbackrest/
mkdir -p /etc/pgbackrest
mkdir -p /etc/pgbackrest/conf.d
touch /etc/pgbackrest/pgbackrest.conf
chmod 640 /etc/pgbackrest/pgbackrest.conf
chown postgres.postgres -R /etc/pgbackrest/
3.编译安装pgbackrest备份工具
su - postgres
unzip pgbackrest-release-2.49.zip
cd pgbackrest-release-2.49/
ls
CODING.md CONTRIBUTING.md LICENSE README.md doc meson.build meson_options.txt src test
cd src/
./configure
make -j 24
make install -j 24
4.验证版本和命令
-bash-4.2$ pgbackrest version
pgBackRest 2.49
-bash-4.2$ pgbackrest help
pgBackRest 2.49 - General help
Usage:
pgbackrest [options] [command]
Commands:
annotate Add or modify backup annotation.
archive-get Get a WAL segment from the archive.
archive-push Push a WAL segment to the archive.
backup Backup a database cluster.
check Check the configuration.
expire Expire backups that exceed retention.
help Get help.
info Retrieve information about backups.
repo-get Get a file from a repository.
repo-ls List files in a repository.
restore Restore a database cluster.
server pgBackRest server.
server-ping Ping pgBackRest server.
stanza-create Create the required stanza data.
stanza-delete Delete a stanza.
stanza-upgrade Upgrade a stanza.
start Allow pgBackRest processes to run.
stop Stop pgBackRest processes from running.
verify Verify contents of the repository.
version Get version.
Use 'pgbackrest help [command]' for more information.
三、使用方式
1.配置数据库的 archive_command 命令
开启归档，修改archive_command
stanza是指备份集的名称，可以在pgBackRest的配置文件中进行设置。
vi postgresql.conf
archive_mode = on
archive_command = 'pgbackrest --stanza=pgxmaster archive-push %p'
需要修改archive_command并开启归档，否则可能有相关报错和提示
2.初始化实例(创建 Stanza)
pgbackrest --stanza=pgxmaster --log-level-console=info stanza-create
执行结果如下：
-bash-4.2$ pgbackrest --stanza=pgxmaster --log-level-console=info stanza-create
2023-12-29 20:53:25.054 P00 INFO: stanza-create command begin 2.49: --exec-id=59466-2c8ab1f2 --log-level-console=info --log-path=/var/log/pgbackrest --pg1-path=/data/pg16/data --pg1-port=5432 --pg1-socket-path=/tmp --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --stanza=pgxmaster
2023-12-29 20:53:25.681 P00 INFO: stanza-create for stanza 'pgxmaster' on repo1
2023-12-29 20:53:25.703 P00 INFO: stanza-create command end: completed successfully (652ms)
3.修改配置文件
vi /etc/pgbackrest/pgbackrest.conf
-bash-4.2$ cat /etc/pgbackrest/pgbackrest.conf
[pgxmaster]
pg01-path=/data/pg16/data
pg01-port=5432
pg01-socket-path=/tmp
#pg1-user=postgres
#pg1-host-config-path=/etc/pgbackrest
#pg1-host-port=22
#pg1-host-user=postgres
[global]
#repo1-path指定 备份和归档仓库路径
repo1-path=/var/lib/pgsql/pgbackreset_bakdir
backup-user=pgsql
retention-full=2
#repo1-cipher-pass=
#repo1-cipher-type=aes-256-cbc
start-fast=y
process-max=3
log-path=/var/log/pgbackrest
[global:archive-push]
#compress-level指定压缩级别
compress-level=3
如果需要进行远程备份，需要配置pg1-host、pg1-host-port、pg1-host-user等。
4.检查配置
pgbackrest --stanza=pgxmaster --log-level-console=info check
执行结果如下：
-bash-4.2$ pgbackrest --stanza=pgxmaster --log-level-console=info check
2023-12-29 20:54:27.959 P00 INFO: check command begin 2.49: --exec-id=59474-9f746218 --log-level-console=info --log-path=/var/log/pgbackrest --pg1-path=/data/pg16/data --pg1-port=5432 --pg1-socket-path=/tmp --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --stanza=pgxmaster
2023-12-29 20:54:28.575 P00 INFO: check repo1 configuration (primary)
2023-12-29 20:54:28.587 CST [59475] LOG: restore point "pgBackRest Archive Check" created at 0/9000090
2023-12-29 20:54:28.587 CST [59475] STATEMENT: select pg_catalog.pg_create_restore_point('pgBackRest Archive Check')::text
2023-12-29 20:54:29.293 P00 INFO: check repo1 archive for WAL (primary)
2023-12-29 20:54:29.396 P00 INFO: WAL segment 000000010000000000000009 successfully archived to '/var/lib/pgsql/pgbackreset_bakdir/archive/pgxmaster/16-1/0000000100000000/000000010000000000000009-1ff7c856c782639a8401763893d294e666946657.gz' on repo1
2023-12-29 20:54:29.397 P00 INFO: check command end: completed successfully (1439ms)
5.全量备份
使用 pgbackrest help backup命令可以查看备份可以带的一些命令参数
pgbackrest help backup
全量备份命令如下
pgbackrest --stanza=pgxmaster --log-level-console=info backup --type=full
执行结果如下：
-bash-4.2$ pgbackrest --stanza=pgxmaster --log-level-console=info backup --type=full
2023-12-29 21:02:03.548 P00 INFO: backup command begin 2.49: --exec-id=59518-ff63d8ae --log-level-console=info --log-path=/var/log/pgbackrest --pg1-path=/data/pg16/data --pg1-port=5432 --pg1-socket-path=/tmp --process-max=3 --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --repo1-retention-full=2 --stanza=pgxmaster --start-fast --type=full
2023-12-29 21:02:04.283 P00 INFO: execute non-exclusive backup start: backup begins after the requested immediate checkpoint completes
2023-12-29 21:02:04.705 CST [59454] LOG: checkpoint starting: immediate force wait
2023-12-29 21:02:04.730 CST [59454] LOG: checkpoint complete: wrote 19 buffers (0.1%); 0 WAL file(s) added, 0 removed, 0 recycled; write=0.010 s, sync=0.008 s, total=0.026 s; sync files=16, longest=0.006 s, average=0.001 s; distance=16384 kB, estimate=29633 kB; lsn=0/B000098, redo lsn=0/B000060
2023-12-29 21:02:04.991 P00 INFO: backup start archive = 00000001000000000000000B, lsn = 0/B000060
2023-12-29 21:02:04.992 P00 INFO: check archive for prior segment 00000001000000000000000A
2023-12-29 21:02:07.833 P00 INFO: execute non-exclusive backup stop and wait for all WAL segments to archive
2023-12-29 21:02:08.237 P00 INFO: backup stop archive = 00000001000000000000000B, lsn = 0/B000138
2023-12-29 21:02:08.244 P00 INFO: check archive for segment(s) 00000001000000000000000B:00000001000000000000000B
2023-12-29 21:02:08.279 P00 INFO: new backup label = 20231229-210204F
2023-12-29 21:02:08.380 P00 INFO: full backup size = 23MB, file total = 974
2023-12-29 21:02:08.380 P00 INFO: backup command end: completed successfully (4835ms)
2023-12-29 21:02:08.380 P00 INFO: expire command begin 2.49: --exec-id=59518-ff63d8ae --log-level-console=info --log-path=/var/log/pgbackrest --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --repo1-retention-full=2 --stanza=pgxmaster
2023-12-29 21:02:08.390 P00 INFO: expire command end: completed successfully (10ms)
查看备份
-bash-4.2$ date
Fri Dec 29 21:03:05 CST 2023
-bash-4.2$ pgbackrest info
stanza: pgxmaster
status: ok
cipher: none
db (current)
wal archive min/max (16): 000000010000000000000008/00000001000000000000000B
full backup: 20231229-210204F
timestamp start/stop: 2023-12-29 21:02:04+08 / 2023-12-29 21:02:08+08
wal start/stop: 00000001000000000000000B / 00000001000000000000000B
database size: 23MB, database backup size: 23MB
repo1: backup set size: 3MB, backup size: 3MB
备份路径分成两个，archive和backup两个路径
具体结构如下
-bash-4.2$ pwd
/var/lib/pgsql/pgbackreset_bakdir
-bash-4.2$ tree -d
.
├── archive
│ └── pgxmaster
│ └── 16-1
│ └── 0000000100000000
└── backup
└── pgxmaster
├── 20231229-210204F
│ └── pg_data
│ ├── base
│ │ ├── 1
│ │ ├── 14484
│ │ └── 4
│ ├── global
│ ├── pg_commit_ts
│ ├── pg_dynshmem
│ ├── pg_logical
│ │ ├── mappings
│ │ └── snapshots
│ ├── pg_multixact
│ │ ├── members
│ │ └── offsets
│ ├── pg_notify
│ ├── pg_replslot
│ ├── pg_serial
│ ├── pg_snapshots
│ ├── pg_stat
│ ├── pg_stat_tmp
│ ├── pg_subtrans
│ ├── pg_tblspc
│ ├── pg_twophase
│ ├── pg_upgrade_output.d
│ │ ├── 20231229T185426.620
│ │ │ ├── dump
│ │ │ └── log
│ │ └── 20231229T185705.267
│ │ ├── dump
│ │ └── log
│ ├── pg_wal
│ │ └── archive_status
│ └── pg_xact
├── backup.history
│ └── 2023
└── latest -> 20231229-210204F
43 directories
---------------------------------------------------------------------------------------------------------------
//backup下每个备份实例对应一个目录，下边带有版本号的目录里存储wal归档相关备份，archive.info里存放归档备份相关信息。
-bash-4.2$ pwd
/var/lib/pgsql/pgbackreset_bakdir/backup/pgxmaster
-bash-4.2$ ls
20231229-210204F backup.history backup.info backup.info.copy latest
-bash-4.2$ cat backup.info
[backrest]
backrest-format=5
backrest-version="2.49"
[backup:current]
20231229-210204F={"backrest-format":5,"backrest-version":"2.49","backup-archive-start":"00000001000000000000000B","backup-archive-stop":"00000001000000000000000B","backup-error":false,"backup-info-repo-size":3225873,"backup-info-repo-size-delta":3225873,"backup-info-size":24131917,"backup-info-size-delta":24131917,"backup-lsn-start":"0/B000060","backup-lsn-stop":"0/B000138","backup-timestamp-start":1703854924,"backup-timestamp-stop":1703854928,"backup-type":"full","db-id":1,"option-archive-check":true,"option-archive-copy":false,"option-backup-standby":false,"option-checksum-page":false,"option-compress":true,"option-hardlink":false,"option-online":true}
[db]
db-catalog-version=202307071
db-control-version=1300
db-id=1
db-system-id=7317967753805234269
db-version="16"
[db:history]
1={"db-catalog-version":202307071,"db-control-version":1300,"db-system-id":7317967753805234269,"db-version":"16"}
[backrest]
backrest-checksum="1bc5921e775f76660ff4ab7e54f04125f2b93ced"
-------------------------------------------------
-bash-4.2$ pwd
/var/lib/pgsql/pgbackreset_bakdir/backup/pgxmaster
-bash-4.2$ ls
20231229-210204F backup.history backup.info backup.info.copy latest
-bash-4.2$ cd 20231229-210204F/
-bash-4.2$ ls
backup.manifest backup.manifest.copy pg_data
-bash-4.2$ cd pg_data/
-bash-4.2$ ls
backup_label.gz pg_dynshmem pg_multixact pg_snapshots pg_tblspc pg_wal
base pg_hba.conf.gz pg_notify pg_stat pg_twophase pg_xact
global pg_ident.conf.gz pg_replslot pg_stat_tmp pg_upgrade_output.d postgresql.auto.conf.gz
pg_commit_ts pg_logical pg_serial pg_subtrans PG_VERSION.gz postgresql.conf.gz
---------------------------------------------------------------------------------------------------------------
//archive下每个备份实例对应一个目录，下边带有版本号的目录里存储wal归档相关备份，backup.info里存放物理备份相关信息。
/var/lib/pgsql/pgbackreset_bakdir/archive/pgxmaster
-bash-4.2$ ls
16-1 archive.info archive.info.copy
-------------------------------------------------
-bash-4.2$ cat archive.info
[backrest]
backrest-format=5
backrest-version="2.49"
[db]
db-id=1
db-system-id=7317967753805234269
db-version="16"
[db:history]
1={"db-id":7317967753805234269,"db-version":"16"}
[backrest]
backrest-checksum="9125f9a1f113ce1ccb7b5d9e13fb5bfacfcfdce4"
-------------------------------------------------
-bash-4.2$ pwd
/var/lib/pgsql/pgbackreset_bakdir/archive/pgxmaster/16-1/0000000100000000
-bash-4.2$ cat 00000001000000000000000B.00000060.backup
START WAL LOCATION: 0/B000060 (file 00000001000000000000000B)
STOP WAL LOCATION: 0/B000138 (file 00000001000000000000000B)
CHECKPOINT LOCATION: 0/B000098
BACKUP METHOD: streamed
BACKUP FROM: primary
START TIME: 2023-12-29 21:02:04 CST
LABEL: pgBackRest backup started at 2023-12-29 21:02:04.486765+08
START TIMELINE: 1
STOP TIME: 2023-12-29 21:02:08 CST
STOP TIMELINE: 1
归档备份如下所示
物理备份如下所示
6.增量备份
pgbackrest --stanza=pgxmaster --log-level-console=info backup --type=incr
执行结果如下所示
-bash-4.2$ pgbackrest --stanza=pgxmaster --log-level-console=info backup --type=incr
2023-12-29 21:15:19.913 P00 INFO: backup command begin 2.49: --exec-id=59681-61772c9f --log-level-console=info --log-path=/var/log/pgbackrest --pg1-path=/data/pg16/data --pg1-port=5432 --pg1-socket-path=/tmp --process-max=3 --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --repo1-retention-full=2 --stanza=pgxmaster --start-fast --type=incr
2023-12-29 21:15:20.721 P00 INFO: last backup label = 20231229-210204F, version = 2.49
2023-12-29 21:15:20.721 P00 INFO: execute non-exclusive backup start: backup begins after the requested immediate checkpoint completes
2023-12-29 21:15:21.532 CST [59454] LOG: checkpoint starting: immediate force wait
2023-12-29 21:15:21.534 CST [59454] LOG: checkpoint complete: wrote 0 buffers (0.0%); 0 WAL file(s) added, 0 removed, 0 recycled; write=0.001 s, sync=0.001 s, total=0.003 s; sync files=0, longest=0.000 s, average=0.000 s; distance=16383 kB, estimate=27115 kB; lsn=0/D000060, redo lsn=0/D000028
2023-12-29 21:15:21.807 P00 INFO: backup start archive = 00000001000000000000000D, lsn = 0/D000028
2023-12-29 21:15:21.807 P00 INFO: check archive for prior segment 00000001000000000000000C
2023-12-29 21:15:23.793 P00 INFO: execute non-exclusive backup stop and wait for all WAL segments to archive
2023-12-29 21:15:24.196 P00 INFO: backup stop archive = 00000001000000000000000D, lsn = 0/D000100
2023-12-29 21:15:24.200 P00 INFO: check archive for segment(s) 00000001000000000000000D:00000001000000000000000D
2023-12-29 21:15:24.233 P00 INFO: new backup label = 20231229-210204F_20231229-211520I
2023-12-29 21:15:24.324 P00 INFO: incr backup size = 8.3KB, file total = 974
2023-12-29 21:15:24.324 P00 INFO: backup command end: completed successfully (4414ms)
2023-12-29 21:15:24.324 P00 INFO: expire command begin 2.49: --exec-id=59681-61772c9f --log-level-console=info --log-path=/var/log/pgbackrest --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --repo1-retention-full=2 --stanza=pgxmaster
2023-12-29 21:15:24.331 P00 INFO: expire command end: completed successfully (7ms)
查看备份如下所示
-bash-4.2$ pgbackrest info
stanza: pgxmaster
status: ok
cipher: none
db (current)
wal archive min/max (16): 000000010000000000000008/00000001000000000000000D
full backup: 20231229-210204F
timestamp start/stop: 2023-12-29 21:02:04+08 / 2023-12-29 21:02:08+08
wal start/stop: 00000001000000000000000B / 00000001000000000000000B
database size: 23MB, database backup size: 23MB
repo1: backup set size: 3MB, backup size: 3MB
incr backup: 20231229-210204F_20231229-211520I
timestamp start/stop: 2023-12-29 21:15:20+08 / 2023-12-29 21:15:24+08
wal start/stop: 00000001000000000000000D / 00000001000000000000000D
database size: 23MB, database backup size: 8.3KB
repo1: backup set size: 3MB, backup size: 438B
backup reference list: 20231229-210204F
-bash-4.2$
-bash-4.2$ date
Fri Dec 29 21:17:52 CST 2023
备份路径下backup数据备份路径下，latest是一个指向最新备份目录的软链。
-bash-4.2$ pwd
/var/lib/pgsql/pgbackreset_bakdir/backup/pgxmaster
-bash-4.2$ ll
total 8
drwxr-x--- 3 postgres postgres 72 Dec 29 21:02 20231229-210204F
drwxr-x--- 3 postgres postgres 72 Dec 29 21:15 20231229-210204F_20231229-211520I
drwxr-x--- 3 postgres postgres 18 Dec 29 21:02 backup.history
-rw-r----- 1 postgres postgres 1797 Dec 29 21:15 backup.info
-rw-r----- 1 postgres postgres 1797 Dec 29 21:15 backup.info.copy
lrwxrwxrwx 1 postgres postgres 33 Dec 29 21:15 latest -> 20231229-210204F_20231229-211520I
backup.info下包含两次备份的信息。
增量备份的backup路径下包含控制文件相关，具体的增量数据，主要还是以wal日志的备份为主。
备份路径下归档备份路径
7.差异备份
pgbackrest --stanza=pgxmaster --log-level-console=info backup --type=diff
先做个数据更改。
-bash-4.2$ psql
psql (16.1)
Type "help" for help.
postgres=# \d tab_ysl
Table "public.tab_ysl"
Column | Type | Collation | Nullable | Default
--------+---------+-----------+----------+---------
id | integer | | |
postgres=# insert into tab_ysl values(6);
INSERT 0 1
执行差异备份
-bash-4.2$ pgbackrest --stanza=pgxmaster --log-level-console=info backup --type=diff
2023-12-29 21:46:54.601 P00 INFO: backup command begin 2.49: --exec-id=59867-16372c14 --log-level-console=info --log-path=/var/log/pgbackrest --pg1-path=/data/pg16/data --pg1-port=5432 --pg1-socket-path=/tmp --process-max=3 --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --repo1-retention-full=2 --stanza=pgxmaster --start-fast --type=diff
2023-12-29 21:46:55.382 P00 INFO: last backup label = 20231229-210204F, version = 2.49
2023-12-29 21:46:55.382 P00 INFO: execute non-exclusive backup start: backup begins after the requested immediate checkpoint completes
2023-12-29 21:46:55.830 CST [59454] LOG: checkpoint starting: immediate force wait
2023-12-29 21:46:55.840 CST [59454] LOG: checkpoint complete: wrote 2 buffers (0.0%); 0 WAL file(s) added, 0 removed, 0 recycled; write=0.003 s, sync=0.002 s, total=0.010 s; sync files=2, longest=0.001 s, average=0.001 s; distance=16383 kB, estimate=25076 kB; lsn=0/F000060, redo lsn=0/F000028
2023-12-29 21:46:56.096 P00 INFO: backup start archive = 00000001000000000000000F, lsn = 0/F000028
2023-12-29 21:46:56.096 P00 INFO: check archive for prior segment 00000001000000000000000E
2023-12-29 21:46:57.771 P00 INFO: execute non-exclusive backup stop and wait for all WAL segments to archive
2023-12-29 21:46:58.176 P00 INFO: backup stop archive = 00000001000000000000000F, lsn = 0/F000100
2023-12-29 21:46:58.178 P00 INFO: check archive for segment(s) 00000001000000000000000F:00000001000000000000000F
2023-12-29 21:46:58.308 P00 INFO: new backup label = 20231229-210204F_20231229-214655D
2023-12-29 21:46:58.371 P00 INFO: diff backup size = 24.3KB, file total = 974
2023-12-29 21:46:58.371 P00 INFO: backup command end: completed successfully (3773ms)
2023-12-29 21:46:58.372 P00 INFO: expire command begin 2.49: --exec-id=59867-16372c14 --log-level-console=info --log-path=/var/log/pgbackrest --repo1-path=/var/lib/pgsql/pgbackreset_bakdir --repo1-retention-full=2 --stanza=pgxmaster
2023-12-29 21:46:58.382 P00 INFO: expire command end: completed successfully (11ms)
查看备份
差异备份方式在backup目录下主要包含发生变化的对象的数据文件。
-bash-4.2$ pwd
/var/lib/pgsql/pgbackreset_bakdir/backup/pgxmaster/20231229-210204F_20231229-214655D
-bash-4.2$ cd pg_data/
-bash-4.2$ ls
backup_label.gz base global pg_logical pg_xact
-bash-4.2$ tree
.
├── backup_label.gz
├── base
│ └── 14484
│ └── 24594.gz
├── global
│ └── pg_control.gz
├── pg_logical
│ └── replorigin_checkpoint.gz
└── pg_xact
└── 0000.gz
5 directories, 5 files
postgres=# select pg_relation_filepath('tab_ysl');
pg_relation_filepath
----------------------
base/14484/24594
(1 row)
archive备份 目录下
8.查看备份情况
pgbackrest info --repo-path=path
如果写了配置文件，可以省略–repo-path=path ，走配置文件。
-bash-4.2$ pgbackrest info
stanza: pgxmaster
status: ok
cipher: none
db (current)
wal archive min/max (16): 000000010000000000000008/00000001000000000000000D
full backup: 20231229-210204F
timestamp start/stop: 2023-12-29 21:02:04+08 / 2023-12-29 21:02:08+08
wal start/stop: 00000001000000000000000B / 00000001000000000000000B
database size: 23MB, database backup size: 23MB
repo1: backup set size: 3MB, backup size: 3MB
incr backup: 20231229-210204F_20231229-211520I
timestamp start/stop: 2023-12-29 21:15:20+08 / 2023-12-29 21:15:24+08
wal start/stop: 00000001000000000000000D / 00000001000000000000000D
database size: 23MB, database backup size: 8.3KB
repo1: backup set size: 3MB, backup size: 438B
backup reference list: 20231229-210204F
9.监控备份信息
doc/example下有两个SQL文件，使用这两个文件可以帮助我们监控上一次成功备份的状态，
psql -f pgsql-pgbackrest-info.sql
psql -f pgsql-pgbackrest-query.sql
执行结果如下
-bash-4.2$ psql -f pgsql-pgbackrest-info.sql
CREATE SCHEMA
CREATE FUNCTION
-bash-4.2$ psql -f pgsql-pgbackrest-query.sql
name | last_successful_backup | last_archived_wal
-------------+------------------------+--------------------------
"pgxmaster" | 2023-12-29 21:46:58+08 | 000000010000000000000011
(1 row)
同样的，pgbackrest info可以查看更详细的备份信息
10.恢复数据
常用的一些例子如下：
–delta参数可以进行增量恢复
pgbackrest --stanza=pgxmaster --delta=2024-01-01 restore
-基于时间点恢复
pgbackrest --stanza=pgxmaster --delta --log-level-console=detail --type=time "--target=2023-12-29 21:46:58+08" restore
-设置恢复目录
pgbackrest --stanza=pgxmaster --set=restore-command="cp %f /var/lib/pgsql/16/data/pg_restore/%p" restore
也可以使用 pgbackrest help restore查看可以添加的一些参数选项。如下是一个实际恢复数据的案例
创建恢复路径
-bash-4.2$ mkdir /data/pg16/data2
查看可用备份
-bash-4.2$ pgbackrest info
stanza: pgxmaster
status: ok
cipher: none
db (current)
wal archive min/max (16): 000000010000000000000008/000000010000000000000012
full backup: 20231229-210204F
timestamp start/stop: 2023-12-29 21:02:04+08 / 2023-12-29 21:02:08+08
wal start/stop: 00000001000000000000000B / 00000001000000000000000B
database size: 23MB, database backup size: 23MB
repo1: backup set size: 3MB, backup size: 3MB
incr backup: 20231229-210204F_20231229-211520I
timestamp start/stop: 2023-12-29 21:15:20+08 / 2023-12-29 21:15:24+08
wal start/stop: 00000001000000000000000D / 00000001000000000000000D
database size: 23MB, database backup size: 8.3KB
repo1: backup set size: 3MB, backup size: 438B
backup reference list: 20231229-210204F
diff backup: 20231229-210204F_20231229-214655D
timestamp start/stop: 2023-12-29 21:46:55+08 / 2023-12-29 21:46:58+08
wal start/stop: 00000001000000000000000F / 00000001000000000000000F
database size: 23MB, database backup size: 24.3KB
repo1: backup set size: 3MB, backup size: 590B
backup reference list: 20231229-210204F
恢复命令
-bash-4.2$ pgbackrest --stanza=pgxmaster --delta --log-level-console=detail --type=time "--target=2023-12-29 21:15:24+08" restore --repo-path=/var/lib/pgsql/pgbackreset_bakdir --pg1-path=/data/pg16/data2
可以配置recovery相关参数，然后拉起数据库后，再使用pg_wal_replay_resume()函数提升为主节点。
11.远程备份
数据库端配置文件里的repo1-host写远程备份节点的主机名或IP，远程备份节点的配置文件里的pg1-host写数据库锁在节点的主机名或者IP，并且需要开通两个节点的SSH。设置免密。
11.1数据库端配置
pgbackrest.conf配置
vi /etc/pgbackrest/pgbackrest.conf
[global]
log-level-file=detail
repo1-host=node_back
log-path=/var/log/pgbackrest
[pgxmaster]
pg1-path=/data/pg16/data
设置数据库参数
vi postgresql.auto.conf
archive_command = 'pgbackrest --stanza=pgxmaster archive-push %p'
archive_mode = on
listen_addresses = '*'
log_line_prefix = ''
max_wal_senders = 3
wal_level = replica
重启数据库
pg_ctl restart
11.2 备份端配置
vi /etc/pgbackrest/pgbackrest.conf
[global]
repo1-path=/data/pg16/data
repo1-retention-full=2
log-path=/var/log/pgbackrest
#compress-type=gz
[global:archive_push]
compress-level=3
[pgxmaster]
pg1-path=/u01/postgresql/data/
pg1-host-config-path=/etc/pgbackrest
pg1-host-port=22
pg1-host-user=postgres
pg1-host=node_database
pg1-port=5432
pg1-user=postgres
备注：
repo1-path 指定 备份和归档仓库路径
compress-level 指定压缩级别 bz2 - 9 ; gz - 6 ; lz4 - 1 ; zst - 3
11.3 创建存储空间
需要在远程控制端进行初始化，在远程控制端完成初始化后，再在数据库端进行初始化
两个节点都需要执行如下命令。
pgbackrest --stanza=pgxmaster --log-level-console=info stanza-create
11.4 备份测试
远程节点执行备份相关命令
可以参照前文部分，此处略。
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