怎样使用 RMAN 增量备份恢复 data guard log gap（日志断档）

主库查询最小scn 信息：

SQL> col current_scn for 999999999999999

SQL>  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

----------------

  12614205226673

  

MIN(FHSCN)

----------------

12614205076072

  

MIN(F.FHSCN)

----------------

12614205076072

 

+++++++++++++++++++++++++++++++++++++++++++++++=





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 端依据第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 在备库端注冊备份片，注意用户属主。权限

RMAN> CATALOG START WITH '/lixora/ForStandby'; 





6.----运行恢复

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 控制文件复制到备库，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.-----更新控制文件里的数据文件信息

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，主库没有加入过新的数据文件。

SELECT FILE#, NAME FROM V$DATAFILE WHERE CREATION_CHANGE# > 12611050666604；

假设有记录。则不能进行witch 操作，能够參考一下文档来恢复：

rman 增量恢复 dg gap后 主库加入新数据文件

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;



假设遇到一些因为设置 nologgling 而导致部分数据丢失，能够安装下述方法来进行恢复

To resolve NOLOGGING operations only, see Note 958181.1.   

In addition to this information, see the online documentation:

10.2:  http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/scenarios.htm#CIHIAADC

11.1:  http://download.oracle.com/docs/cd/B28359_01/server.111/b28294/rman.htm#SBYDB00759

11.2: http://download.oracle.com/docs/cd/E11882_01/server.112/e17022/rman.htm#CIHIAADC





后记

假设要启用实时应用，须要在备库加入standby redo log，大小应和主库一样。且比主库多一组。





ALTER DATABASE add standby LOGFILE GROUP 6 size 500M;

ALTER DATABASE add standby LOGFILE GROUP 7 size 500M;

ALTER DATABASE add standby LOGFILE GROUP 8 size 500M;

ALTER DATABASE add standby LOGFILE GROUP 9 size 500M;





启用命令：

ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE;

详细内容參见：

oracle 10g standby database 实时应用 redo 数据

怎样确保dg 已经正常，后台日志类似例如以下：

Mon Dec 22 10:03:04 CST 2014

RFS[1]: Archived Log: '+DATA/lixora/archivelog/1_23094_790186477.dbf'

Mon Dec 22 10:03:25 CST 2014

Media Recovery Log +DATA/lixora/archivelog/1_23094_790186477.dbf

Media Recovery Waiting for thread 1 sequence 23095 (in transit)

Mon Dec 22 10:05:53 CST 2014

RFS[2]: Archived Log: '+DATA/lixora/archivelog/1_23095_790186477.dbf'

Primary database is in MAXIMUM PERFORMANCE mode

RFS[2]: No standby redo logfiles of size 1024000 blocks exist

Mon Dec 22 10:05:55 CST 2014

Media Recovery Log +DATA/zhglptdg/archivelog/1_23095_790186477.dbf

Media Recovery Waiting for thread 1 sequence 23096 (in transit)

Mon Dec 22 10:05:57 CST 2014

RFS[2]: Archived Log: '+DATA/lixora/archivelog/1_23096_790186477.dbf'

Primary database is in MAXIMUM PERFORMANCE mode

RFS[2]: No standby redo logfiles of size 1024000 blocks exist

Mon Dec 22 10:06:00 CST 2014

Media Recovery Log +DATA/lixora/archivelog/1_23096_790186477.dbf

Media Recovery Waiting for thread 1 sequence 23097 (in transit)









类似一下日志，表明日志仅仅是传过来。可是没有应用：

Tue Dec 16 17:28:48 CST 2014

Primary database is in MAXIMUM PERFORMANCE mode

RFS[3]: Successfully opened standby log 7: '+DATA/lixora/onlinelog/group_7.360.857131345'

Tue Dec 16 18:57:12 CST 2014

Primary database is in MAXIMUM PERFORMANCE mode

RFS[3]: Successfully opened standby log 8: '+DATA/lixora/onlinelog/group_8.361.857131375'

Tue Dec 16 20:12:13 CST 2014

Primary database is in MAXIMUM PERFORMANCE mode

RFS[3]: Successfully opened standby log 7: '+DATA/lixora/onlinelog/group_7.360.857131345'

Tue Dec 16 21:40:39 CST 2014

Primary database is in MAXIMUM PERFORMANCE mode

RFS[3]: Successfully opened standby log 8: '+DATA/lixora/onlinelog/group_8.361.857131375'









怎样能够确保dg 正常：

1）v$archive_log.applied  是否为yes

2）主库切换日志：ALTER system swtich logfile。

看备库v$database.CURRENT_SCN 是否有增长？