如何通过rman的增量备份恢复dataguard中standby端的数据

2025-05-04 22:38:35
推荐回答(1个)
回答1:

1.----备库取消归档应用
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;

2.----备库确定 lowest scn

col current_scn for 99999999999999
SELECT CURRENT_SCN FROM V$DATABASE;

select min(fhscn) from x$kcvfh;

select min(f.fhscn) from x$kcvfh f, v$datafile d
where f.hxfil =d.file#
and d.enabled != 'READ ONLY' ;

取上述查询中的最小值

SQL> col current_scn for 999999999999999999
SQL> SELECT CURRENT_SCN FROM V$DATABASE;

CURRENT_SCN
-------------------
12611050666604

SQL> select min(fhscn) from x$kcvfh;

MIN(FHSCN)
----------------
12611050666605

SQL> select min(f.fhscn) from x$kcvfh f, v$datafile d
where f.hxfil =d.file#
and d.enabled != 'READ ONLY' ; 2 3

MIN(F.FHSCN)
----------------
12611050666605

3.-----on primary db 端根据第2步中获取的最小scn 来进行增量备份
BACKUP INCREMENTAL FROM SCN 12611050666604 DATABASE FORMAT '/lixora/ForStandby_%U' tag 'FORSTANDBY';

4.-----拷贝备份到 备库
$scp ForStandby_07pqprm4_1_1 192.168.0.10:/tmp

5.----on standby db 在备库端注册备份片,注意用户属主,权限
RMAN> CATALOG START WITH '/lixora/ForStandby';

6.----执行恢复
RMAN> RECOVER DATABASE NOREDO;

7.-----on primary db 生成新的standby 控制文件
RMAN> BACKUP CURRENT CONTROLFILE FOR STANDBY FORMAT '/lixora/ForStandbyCTRL.bck';

8.----把主库端生成的standby 控制文件拷贝到备库,注意用户属主,权限

RMAN> BACKUP CURRENT CONTROLFILE FOR STANDBY FORMAT '/lixora/ForStandbyCTRL.bck';

scp /lixora/ForStandbyCTRL.bck 192.168.0.10:/tmp

9.------备份备库数据文件信息,用于在恢复新的standby 控制文件后比对

spool datafile_names_step8.txt
set lines 200
col name format a60
select file#, name from v$datafile order by file# ;
spool off

10.------on standby Db 恢复新的standby 控制文件

RMAN> SHUTDOWN IMMEDIATE ;
RMAN> STARTUP NOMOUNT;
RMAN> RESTORE STANDBY CONTROLFILE FROM '/tmp/ForStandbyCTRL.bck';

11.-----更新控制文件中的数据文件信息
使新的standby 控制文件生效

RMAN> SHUTDOWN;
RMAN> STARTUP MOUNT;

CATALOG START WITH '+DATA/zhglptdg/datafile/';

12.------on primary db。确保在备库发生日志gap 后,主库没有添加过新的数据文件。
SELECT FILE#, NAME FROM V$DATAFILE WHERE CREATION_CHANGE# > 12611050666604;

如果有记录,则不能进行witch 操作,可以参考一下文档来恢复:
Note 1531031.1 Steps to perform for Rolling forward a standby database using RMAN incremental backup when datafile is added to primary

13.-----重命名数据文件
RMAN> SWITCH DATABASE TO COPY;

14.-----再次确认在恢复增量备份片后主库和备库scn 差距没有太大

SQL> col current_scn for 99999999999999
SELECT CURRENT_SCN FROM V$DATABASE;

select min(fhscn) from x$kcvfh;

select min(f.fhscn) from x$kcvfh f, v$datafile d
where f.hxfil =d.file#
and d.enabled != 'READ ONLY' ;

CURRENT_SCN
---------------
12614205662375

MIN(FHSCN)
----------------
12614205076072

MIN(F.FHSCN)
----------------
12614205076072

15.------ On standby database, 清理standby 日志组

select * from v$standby_log;

SQL> ALTER DATABASE CLEAR LOGFILE GROUP 1;
SQL> ALTER DATABASE CLEAR LOGFILE GROUP 2;
SQL> ALTER DATABASE CLEAR LOGFILE GROUP 3;

16.------启动redo data apply
SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT;