使用RMAN备份与恢复数据库（7）——管理备份集
通过RMAN有两种不同类型的备份方式：使用镜像备份和使用备份集备份。
镜像备份（Image Copies）：镜像复制其实就是创建数据文件、控制文件或归档文件的副本，与用户通过操作系统命令创建的备份一样，RMAN利用目标数据库中的服务进程来完成文件复制。
备份集（Backup Sets）：为RMAN默认的备份选项。备份集是RMAN创建的具有特定格式的逻辑备份对象，备份集在逻辑上由一个或多个备份片段（Backup Piece）组成，每个备份片段在物理上对应一个操作系统文件，一个备份片段中可能包含多个数据文件、控制文件或归档文件。使用备份集备份时只读取数据库中已经使用的数据块，因此备份文件的体积更小。
一、查看和修改RMAN的备份方式
1、查看RMAN的备份方式
RMAN> show all;RMAN configuration parameters for database with db_unique_name ORCL are:CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # defaultCONFIGURE BACKUP OPTIMIZATION OFF; # defaultCONFIGURE DEFAULT DEVICE TYPE TO DISK; # defaultCONFIGURE CONTROLFILE AUTOBACKUP OFF; # defaultCONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default--#################################################################################--下面的配置表示当前的备份方式为备份集备份CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default--#################################################################################CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # defaultCONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # defaultCONFIGURE CHANNEL DEVICE TYPE DISK FORMAT '/home/oracle/rmanbak/%u';CONFIGURE MAXSETSIZE TO UNLIMITED; # defaultCONFIGURE ENCRYPTION FOR DATABASE OFF; # defaultCONFIGURE ENCRYPTION ALGORITHM 'AES128'; # defaultCONFIGURE COMPRESSION ALGORITHM 'BASIC' AS OF RELEASE 'DEFAULT' OPTIMIZE FOR LOAD TRUE ; # defaultCONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # defaultCONFIGURE SNAPSHOT CONTROLFILE NAME TO '/usr/local/oracle/product/11.2.0/db_1/dbs/snapcf_orcl.f'; # default
2、修改RMAN的备份方式
RMAN> CONFIGURE DEVICE TYPE DISK PARALLELISM 2 BACKUP TYPE TO COPY; new RMAN configuration parameters:CONFIGURE DEVICE TYPE DISK PARALLELISM 2 BACKUP TYPE TO COPY;new RMAN configuration parameters are successfully storedreleased channel: ORA_DISK_1RMAN> show all;RMAN configuration parameters for database with db_unique_name ORCL are:CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # defaultCONFIGURE BACKUP OPTIMIZATION OFF; # defaultCONFIGURE DEFAULT DEVICE TYPE TO DISK; # defaultCONFIGURE CONTROLFILE AUTOBACKUP OFF; # defaultCONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default--#################################################################################--备份方式修改为镜像备份CONFIGURE DEVICE TYPE DISK PARALLELISM 2 BACKUP TYPE TO COPY;--#################################################################################CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # defaultCONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # defaultCONFIGURE CHANNEL DEVICE TYPE DISK FORMAT '/home/oracle/rmanbak/%u';CONFIGURE MAXSETSIZE TO UNLIMITED; # defaultCONFIGURE ENCRYPTION FOR DATABASE OFF; # defaultCONFIGURE ENCRYPTION ALGORITHM 'AES128'; # defaultCONFIGURE COMPRESSION ALGORITHM 'BASIC' AS OF RELEASE 'DEFAULT' OPTIMIZE FOR LOAD TRUE ; # defaultCONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # defaultCONFIGURE SNAPSHOT CONTROLFILE NAME TO '/usr/local/oracle/product/11.2.0/db_1/dbs/snapcf_orcl.f'; # default
3、把备份方式重新修改为备份集
RMAN> CONFIGURE DEVICE TYPE DISK PARALLELISM 2 BACKUP TYPE TO BACKUPSET; old RMAN configuration parameters:CONFIGURE DEVICE TYPE DISK PARALLELISM 2 BACKUP TYPE TO COPY;new RMAN configuration parameters:CONFIGURE DEVICE TYPE DISK PARALLELISM 2 BACKUP TYPE TO BACKUPSET;new RMAN configuration parameters are successfully storedRMAN> show all;RMAN configuration parameters for database with db_unique_name ORCL are:CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # defaultCONFIGURE BACKUP OPTIMIZATION OFF; # defaultCONFIGURE DEFAULT DEVICE TYPE TO DISK; # defaultCONFIGURE CONTROLFILE AUTOBACKUP OFF; # defaultCONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default--#################################################################################--备份方式修改为备份集备份--PARALLELISM参数为并行数CONFIGURE DEVICE TYPE DISK PARALLELISM 2 BACKUP TYPE TO BACKUPSET;--#################################################################################CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # defaultCONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # defaultCONFIGURE CHANNEL DEVICE TYPE DISK FORMAT '/home/oracle/rmanbak/%u';CONFIGURE MAXSETSIZE TO UNLIMITED; # defaultCONFIGURE ENCRYPTION FOR DATABASE OFF; # defaultCONFIGURE ENCRYPTION ALGORITHM 'AES128'; # defaultCONFIGURE COMPRESSION ALGORITHM 'BASIC' AS OF RELEASE 'DEFAULT' OPTIMIZE FOR LOAD TRUE ; # defaultCONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # defaultCONFIGURE SNAPSHOT CONTROLFILE NAME TO '/usr/local/oracle/product/11.2.0/db_1/dbs/snapcf_orcl.f'; # default
在备份集备份方式下也可以使用镜像备份，只需要使用backup as copy命令即可。
二、查看备份集
1、查看参数文件备份集
RMAN> list backup of spfile;List of Backup Sets===================BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------59Full 80.00KDISK 00:00:00-04-10 06:13:03BP Key: 91 Status: AVAILABLE Compressed: NO Tag: TAGT061303Piece Name: /home/oracle/rmanbak/spfileorcl.oldSPFILE Included: Modification time: -04-10 05:34:50SPFILE db_unique_name: ORCL
2、查看控制文件备份集
RMAN> list backup of controlfile;List of Backup Sets===================BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------60Full 9.83MDISK 00:00:02-04-10 06:13:38BP Key: 92 Status: AVAILABLE Compressed: NO Tag: TAGT061336Piece Name: /home/oracle/rmanbak/control01.oldControl File Included: Ckp SCN: 1766092Ckp time: -04-10 06:13:36
3、查看数据文件备份集
RMAN> list backup of datafile 5;List of Backup Sets===================BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------57Full 18.42MDISK 00:00:00-04-09 20:28:34BP Key: 89 Status: AVAILABLE Compressed: NO Tag: TAGT202834Piece Name: /home/oracle/rmanbak/data01.dbfList of Datafiles in backup set 57File LV Type Ckp SCN Ckp Time Name---- -- ---- ---------- ------------------- ----5 Full 1741852 -04-09 20:28:34 /usr/local/oradata/orcl/data01.dbf
4、查看表空间备份集
说明：表空间和数据文件备份结果相同。
RMAN> list backup of tablespace data01;List of Backup Sets===================BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------57Full 18.42MDISK 00:00:00-04-09 20:28:34BP Key: 89 Status: AVAILABLE Compressed: NO Tag: TAGT202834Piece Name: /home/oracle/rmanbak/data01.dbfList of Datafiles in backup set 57File LV Type Ckp SCN Ckp Time Name---- -- ---- ---------- ------------------- ----5 Full 1741852 -04-09 20:28:34 /usr/local/oradata/orcl/data01.dbf
5、查看归档日志备份集
RMAN> list backup of archivelog all;List of Backup Sets===================BS Key Size Device Type Elapsed Time Completion Time ------- ---------- ----------- ------------ -------------------5814.20MDISK 00:00:02-04-09 20:32:06BP Key: 90 Status: AVAILABLE Compressed: YES Tag: TAGT203204Piece Name: /home/oracle/rmanbak/archivelog_ORCL_1559168802_81_1_List of Archived Logs in backup set 58Thrd SeqLow SCN Low Time Next SCN Next Time---- ------- ---------- ------------------- ---------- ---------1 9 1741038 -04-09 20:20:23 1741173 -04-09 20:21:581 101741173 -04-09 20:21:58 1741284 -04-09 20:22:271 111741284 -04-09 20:22:27 1741391 -04-09 20:22:581 121741391 -04-09 20:22:58 1741661 -04-09 20:23:411 131741661 -04-09 20:23:41 1742829 -04-09 20:30:101 141742829 -04-09 20:30:10 1743756 -04-09 20:30:521 151743756 -04-09 20:30:52 1743788 -04-09 20:32:04
6、查看所有的备份集
RMAN> list backup;List of Backup Sets===================BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------57Full 18.42MDISK 00:00:00-04-09 20:28:34BP Key: 89 Status: AVAILABLE Compressed: NO Tag: TAGT202834Piece Name: /home/oracle/rmanbak/data01.dbfList of Datafiles in backup set 57File LV Type Ckp SCN Ckp Time Name---- -- ---- ---------- ------------------- ----5 Full 1741852 -04-09 20:28:34 /usr/local/oradata/orcl/data01.dbfBS Key Size Device Type Elapsed Time Completion Time ------- ---------- ----------- ------------ -------------------5814.20MDISK 00:00:02-04-09 20:32:06BP Key: 90 Status: AVAILABLE Compressed: YES Tag: TAGT203204Piece Name: /home/oracle/rmanbak/archivelog_ORCL_1559168802_81_1_List of Archived Logs in backup set 58Thrd SeqLow SCN Low Time Next SCN Next Time---- ------- ---------- ------------------- ---------- ---------1 9 1741038 -04-09 20:20:23 1741173 -04-09 20:21:581 101741173 -04-09 20:21:58 1741284 -04-09 20:22:271 111741284 -04-09 20:22:27 1741391 -04-09 20:22:581 121741391 -04-09 20:22:58 1741661 -04-09 20:23:411 131741661 -04-09 20:23:41 1742829 -04-09 20:30:101 141742829 -04-09 20:30:10 1743756 -04-09 20:30:521 151743756 -04-09 20:30:52 1743788 -04-09 20:32:04BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------59Full 80.00KDISK 00:00:00-04-10 06:13:03BP Key: 91 Status: AVAILABLE Compressed: NO Tag: TAGT061303Piece Name: /home/oracle/rmanbak/spfileorcl.oldSPFILE Included: Modification time: -04-10 05:34:50SPFILE db_unique_name: ORCLBS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------60Full 9.83MDISK 00:00:02-04-10 06:13:38BP Key: 92 Status: AVAILABLE Compressed: NO Tag: TAGT061336Piece Name: /home/oracle/rmanbak/control01.oldControl File Included: Ckp SCN: 1766092Ckp time: -04-10 06:13:36
三、使用crosscheck命令核对备份集
crosscheck命令用于核对磁盘和磁带上的备份文件，以确保RMAN资料库与备份文件保持同步。当执行crosscheck命令时，如果资料库记录不匹配于备份文件的物理状态，那么该命令会更新资料库记录的状态信息。备份文件的状态包括：AVALIABLE（可用的）、UNAVALIABLE（不可用的）、EXPIRED（失效的）。crosscheck命令的格式如下：
（1）crosscheck backup; --核对所有备份集（2）crosscheck backup of database; --核对所有数据文件的备份集（3）crosscheck backup of tablespace data01; --核对特定表空间的备份集（4）crosscheck backup of datafile 4; --核对特定数据文件的备份集（5）crosscheck backup of controlfile; --核对控制文件的备份集（6）crosscheck backup of spfile; --核对SPFILE的备份集（7）crosscheck backup of archivelog sequence 3; --核对归档日志的备份集（8）crosscheck copy; --核对所有镜像副本（9）crosscheck copy of database; --核对所有数据文件的镜像副本（10）crosscheck copy of tablespace users; --核对特定表空间的镜像副本（11）crosscheck copy of datafile 6; --核对特定数据文件的镜像副本（12）crosscheck copy of archivelog sequence 4; --核对归档日志的镜像副本（13）crosscheck copy of controlfile; --核对控制文件的镜像副本
举例：
--控制文件的备份被删除，检查之后该备份集的状态变成expired（失效）RMAN> crosscheck backup of controlfile;using channel ORA_DISK_1using channel ORA_DISK_2crosschecked backup piece: found to be 'EXPIRED'backup piece handle=/home/oracle/rmanbak/control01.old RECID=92 STAMP=1037340817Crosschecked 1 objectsRMAN> list backup of controlfile;List of Backup Sets===================BS Key Type LV Size Device Type Elapsed Time Completion Time ------- ---- -- ---------- ----------- ------------ -------------------60Full 9.83MDISK 00:00:02-04-10 06:13:38BP Key: 92 Status: EXPIRED Compressed: NO Tag: TAGT061336Piece Name: /home/oracle/rmanbak/control01.oldControl File Included: Ckp SCN: 1766092Ckp time: -04-10 06:13:36
四、删除备份集
删除备份集之前通常先使用crosscheck命令进行检查。删除备份集的命令如下：
1、删除过期备份
当使用RMAN命令执行备份操作时，RMAN会根据备份冗余策略确定备份是否过期。
RMAN> crosscheck backup;using channel ORA_DISK_1using channel ORA_DISK_2crosschecked backup piece: found to be 'AVAILABLE'backup piece handle=/home/oracle/rmanbak/data01.dbf RECID=89 STAMP=1037305714crosschecked backup piece: found to be 'AVAILABLE'backup piece handle=/home/oracle/rmanbak/archivelog_ORCL_1559168802_81_1_ RECID=90 STAMP=1037305924crosschecked backup piece: found to be 'AVAILABLE'backup piece handle=/home/oracle/rmanbak/spfileorcl.old RECID=91 STAMP=1037340783Crosschecked 3 objectscrosschecked backup piece: found to be 'EXPIRED'backup piece handle=/home/oracle/rmanbak/control01.old RECID=92 STAMP=1037340817Crosschecked 1 objectsRMAN> delete obsolete;RMAN retention policy will be applied to the commandRMAN retention policy is set to redundancy 1using channel ORA_DISK_1using channel ORA_DISK_2Deleting the following obsolete backups and copies:Type Key Completion Time Filename/Handle-------------------- ------ ------------------ --------------------Backup Set 60-04-10 06:13:38Backup Piece 92-04-10 06:13:38 /home/oracle/rmanbak/control01.oldDo you really want to delete the above objects (enter YES or NO)? yesdeleted backup piecebackup piece handle=/home/oracle/rmanbak/control01.old RECID=92 STAMP=1037340817Deleted 1 objects
2、删除无效备份
首先执行CROSSCHECK命令核对备份集，如果发现备份无效（比如备份对应的数据文件损坏或丢失），RMAN会将该备份集标记为 EXPIRED状态。
说明：noprompt参数表示删除时不提示yes或no。
RMAN> delete noprompt expired backup;using channel ORA_DISK_1using channel ORA_DISK_2specification does not match any backup in the repository
3、删除EXPIRED镜像副本
delete expired copy;
4、删除特定备份集
RMAN> delete noprompt backupset 57;using channel ORA_DISK_1using channel ORA_DISK_2List of Backup PiecesBP Key BS Key Pc# Cp# StatusDevice Type Piece Name------- ------- --- --- ----------- ----------- ----------89571 1 AVAILABLE DISK /home/oracle/rmanbak/data01.dbfdeleted backup piecebackup piece handle=/home/oracle/rmanbak/data01.dbf RECID=89 STAMP=1037305714Deleted 1 objects
5、删除特定备份片
RMAN> delete noprompt backuppiece '/home/oracle/rmanbak/archivelog_ORCL_1559168802_81_1_';using channel ORA_DISK_1using channel ORA_DISK_2List of Backup PiecesBP Key BS Key Pc# Cp# StatusDevice Type Piece Name------- ------- --- --- ----------- ----------- ----------90581 1 AVAILABLE DISK /home/oracle/rmanbak/archivelog_ORCL_1559168802_81_1_deleted backup piecebackup piece handle=/home/oracle/rmanbak/archivelog_ORCL_1559168802_81_1_ RECID=90 STAMP=1037305924Deleted 1 objects
6、删除所有备份集
delete noprompt backup;
7、删除所有镜像副本
delete noprompt copy;
8、删除特定镜像副本
delete datafile copy '/home/oracle/rmanbak/data01.dbf';
