PostgreSQL备份之pg_basebackup
一、准备
连接上master节点创建replication用户
# CREATE ROLE replicator with login replication password 123456；
修改白名单pg_hba.conf
# host replication all xxxxx/32 md5
二、制作基础备份
# pg_basebackup --format=tar \ #使用打包方式备份 --xlog-method=fetch \ #获取wal文件方式，等备份结束后把备份期间所有的wal备份 --compress=1 \ #压缩等级 --checkpoint=fast \ #执行检查点的方式 --label=backup \ #标签 --pgdata=/data/backup/ #备份目录 --progress \ #打印过程 --verbose \ #打印详细信息 --host='172.17.5.45' \ #master节点ip --port=5432 \ #master节点端口 --user=postgres #连接master节点的用户 Password: transaction log start point: 2/34000028 on timeline 1 414272/414272 kB (100%), 3/3 tablespaces transaction log end point: 2/34000128 pg_basebackup: base backup completed
备份默认会占用一个max_wal_senders连接，需要设置大一点，还可以使用
-r, --max-rate=RATE maximum transfer rate to transfer data directory
(in kB/s, or use suffix "k" or "M")
限制传输速度
# ll backup/ total 123196 -rw-r--r--. 1 root root 129 Sep 8 01:21 25375.tar.gz -rw-r--r--. 1 root root 128 Sep 8 01:21 25376.tar.gz -rw-r--r--. 1 root root 126141406 Sep 8 01:22 base.tar.gz
base.tar.gz是数据目录的备份，其他两个是表空间的备份
三、恢复
1. 解压缩
# cd /data/backup/ # mkdir pgdata 25375 25376 # tar zxf base.tar.gz -C pgdata/ # ls pgdata/ backup_label global pg_dynshmem pg_ident.conf pg_logical pg_notify pg_serial pg_stat pg_subtrans pg_twophase pg_xlog postgresql.conf base pg_clog pg_hba.conf pg_log pg_multixact pg_replslot pg_snapshots pg_stat_tmp pg_tblspc PG_VERSION postgresql.auto.conf recovery.conf # tar zxf 25375.tar.gz -C 25375 # tar zxf 25376.tar.gz -C 25376 # ls 25375 25375.tar.gz 25376 25376.tar.gz base.tar.gz pgdata
2. 修改表空间软连接
<># ln -sf /data/backup/25375 pgdata/pg_tblspc/25375 [root@node2 backup]# ln -sf /data/backup/25376 pgdata/pg_tblspc/25376 [root@node2 backup]# ll pgdata/pg_tblspc/ total 0 lrwxrwxrwx. 1 root root 18 Sep 8 01:35 25375 -> /data/backup/25375 lrwxrwxrwx. 1 root root 18 Sep 8 01:35 25376 -> /data/backup/25376
3. 修改数据目录权限
# chown -R postgres:postgres pgdata/ 25375 25376 # chmod 0700 pgdata/ # ll total 123208 drwxr-xr-x. 3 postgres postgres 4096 Sep 8 01:32 25375 -rw-r--r--. 1 root root 129 Sep 8 01:21 25375.tar.gz drwxr-xr-x. 3 postgres postgres 4096 Sep 8 01:33 25376 -rw-r--r--. 1 root root 128 Sep 8 01:21 25376.tar.gz -rw-r--r--. 1 root root 126141406 Sep 8 01:22 base.tar.gz drwx------. 19 postgres postgres 4096 Sep 8 01:31 pgdata
4. 启动
# su postgres
$ pg_ctl -D pgdata/ start
server starting
[ 2015-09-08 05:40:04.510 UTC 11107 55ee74b4.2b63 1 0]LOG: redirecting log output to logging collector process
[ 2015-09-08 05:40:04.511 UTC 11107 55ee74b4.2b63 2 0]HINT: Future log output will appear in directory "pg_log".
$ psql
psql (9.4.4)
Type "help" for help.
postgres=# \db+
List of tablespaces
Name | Owner | Location | Access privileges | Options | Description
------------+----------+--------------------+-------------------+---------+-------------
pg_default | postgres | | | |
pg_global | postgres | | | |
tblspc1 | postgres | /data/backup/25375 | | |
tblspc2 | postgres | /data/backup/25376 | | |
(4 rows)
四、 制作从库
1. 获取备份文件
# pg_basebackup --format=plain \ #使用目录方式 --write-recovery-conf \ #生成简单recovery.conf --xlog-method=stream \ #使用stream的方式备份wal文件，会再占用一个max_wal_sender,wal文件一生成就会备份 --checkpoint=fast \ --label=backup \ --pgdata=/data/test_pgdata_94 \ --progress \ --verbose \ --host='172.17.5.45' \ --port=5432 \ --user=postgres Password: transaction log start point: 2/38000028 on timeline 1 pg_basebackup: starting background WAL receiver 397887/397887 kB (100%), 3/3 tablespaces transaction log end point: 2/380000F0 pg_basebackup: waiting for background process to finish streaming ... pg_basebackup: base backup completed
2. 修改目录权限
# chown -R postgres:postgres test_pgdata_94 tblspc1/ tblspc2/ # chmod 0700 test_pgdata_94 # ll test_pgdata_94 total 104 -rw-------. 1 postgres postgres 189 Sep 8 01:43 backup_label drwx------. 6 postgres postgres 4096 Sep 8 01:43 base drwx------. 2 postgres postgres 4096 Sep 8 01:43 global drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_clog drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_dynshmem -rw-------. 1 postgres postgres 4581 Sep 8 01:43 pg_hba.conf -rw-------. 1 postgres postgres 1636 Sep 8 01:43 pg_ident.conf drwxr-xr-x. 2 postgres postgres 4096 Sep 8 01:43 pg_log drwx------. 4 postgres postgres 4096 Sep 8 01:43 pg_logical drwx------. 4 postgres postgres 4096 Sep 8 01:43 pg_multixact drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_notify drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_replslot drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_serial drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_snapshots drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_stat drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_stat_tmp drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_subtrans drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_tblspc drwx------. 2 postgres postgres 4096 Sep 8 01:43 pg_twophase -rw-------. 1 postgres postgres 4 Sep 8 01:43 PG_VERSION drwx------. 3 postgres postgres 4096 Sep 8 01:43 pg_xlog -rw-------. 1 postgres postgres 88 Sep 8 01:43 postgresql.auto.conf -rw-------. 1 postgres postgres 4676 Sep 8 01:43 postgresql.conf -rw-r--r--. 1 postgres postgres 131 Sep 8 01:43 recovery.conf # ll tblspc1/ total 4 drwx------. 2 postgres postgres 4096 Sep 8 01:43 PG_9.4_201409291 # ll tblspc2 total 4 drwx------. 2 postgres postgres 4096 Sep 8 01:43 PG_9.4_201409291
3. 启动
# su postgres
$ pg_ctl -D test_pgdata_94 start
server starting
$ [ 2015-09-08 05:49:55.383 UTC 12100 55ee7703.2f44 1 0]LOG: redirecting log output to logging collector process
[ 2015-09-08 05:49:55.383 UTC 12100 55ee7703.2f44 2 0]HINT: Future log output will appear in directory "pg_log".
$ psql
psql (9.4.4)
Type "help" for help.
postgres=# \db+
List of tablespaces
Name | Owner | Location | Access privileges | Options | Description
------------+----------+---------------+-------------------+---------+-------------
pg_default | postgres | | | |
pg_global | postgres | | | |
tblspc1 | postgres | /data/tblspc1 | | |
tblspc2 | postgres | /data/tblspc2 | | |
(4 rows)
参考：http://www.postgresql.org/docs/9.4/static/app-pgbasebackup.html