1。主库从库归档记录不一致。例如以下所看到的：
做完failover后，坏的旧主库变成了新的从库，可是新从库的归档日志记录不一致，就是archive log list;出来的和v$archived_log出来对不上号，例如以下所看到的：
1.1 主库：
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 8
Next log sequence to archive 10
Current log sequence 10
SQL> SQL> select sequence#,applied from v$archived_log order by sequence# asc;
......
---------- ---------
7527 YES
7527 YES
7528 YES
7528 YES
7529 YES
7530 YES
7531 YES
7532 YES
7533 YES
14529 rows selected.大家能够看到主库中archive log list和v$archived_log记录归档不一致。
1.2 从库：
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 10
Next log sequence to archive 0
Current log sequence 10
SQL> SQL> select sequence#,applied from v$archived_log order by sequence# asc;
SEQUENCE# APPLIED
---------- ---------
9 IN-MEMORY
SQL>从库的归档也一直没有被应用，并且两者也查了一个数字差，一个为10。一个为9。
PS：大家看到主库和从库归档号没有统一起来，不一致。
2，清除新主库的归档记录
问题原因是在新主库上保留的还是旧主库的归档日志记录，须要手工清理一下，在新主库上运行清除记录：
SQL> execute sys.dbms_backup_restore.resetCfileSection(11);
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL> select sequence#,applied from v$archived_log order by sequence# asc;
no rows selected
SQL> 去归档日志文件夹。人为删除旧的归档日志
[oracle@oracle_standby1 archivelog]$ rm -rf 2015_12_13/ 2015_12_19 2015_12_20 2015_12_21 2015_12_22 2015_12_23 2015_12_24 2015_12_25
[oracle@oracle_standby1 archivelog]$ 然后进入rman运行
RMAN> catalog db_recovery_file_dest;
RMAN> catalog db_recovery_file_dest;
using target database control file instead of recovery catalog
searching for all files in the recovery area
List of Files Unknown to the Database
=====================================
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_9_c7c1v5qw_.log
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_7_c7c1ttf1_.log
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_8_c7dst287_.log
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_7_c7dssvfd_.log
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_9_c7dst8wr_.log
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_8_c7c1v0ff_.log
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/archivelog/2015_12_26/o1_mf_1_9_c7wqvrp9_.arc
Do you really want to catalog the above files (enter YES or NO)? YES
cataloging files...
cataloging done
List of Cataloged Files
=======================
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/archivelog/2015_12_26/o1_mf_1_9_c7wqvrp9_.arc
List of Files Which Where Not Cataloged
=======================================
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_9_c7c1v5qw_.log
RMAN-07529: Reason: catalog is not supported for this file type
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_7_c7c1ttf1_.log
RMAN-07529: Reason: catalog is not supported for this file type
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_8_c7dst287_.log
RMAN-07529: Reason: catalog is not supported for this file type
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_7_c7dssvfd_.log
RMAN-07529: Reason: catalog is not supported for this file type
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_9_c7dst8wr_.log
RMAN-07529: Reason: catalog is not supported for this file type
File Name: /oracle/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_8_c7c1v0ff_.log
RMAN-07529: Reason: catalog is not supported for this file type
RMAN> exit
然后进入sql命令查看：
SQL> select sequence#,applied from v$archived_log order by sequence# asc;
SEQUENCE# APPLIED
---------- ---------
9 NO
SQL> 3，之后switch切换日志測试
主库：
SQL> alter system switch logfile;
System altered.
SQL> select sequence#,applied from v$archived_log order by sequence# asc;
SEQUENCE# APPLIED
---------- ---------
9 NO
10 NO
10 NO
SQL> 从库：
SQL> select sequence#,applied from v$archived_log order by sequence# asc;
SEQUENCE# APPLIED
---------- ---------
9 YES
10 YES
SQL> 看到两边归档日志以及被应用情况都一致了。