描述：
Oracle 11g 删除备库所有standby redo log ，查看日志报错，处理方法如下。
报错信息如下：
Additional information: 3
Errors in file /fantlam/oracle/app/oracle/diag/rdbms/mmptdg/mmptdg/trace/mmptdg_rfs_4012.trc:
ORA-00313: open Failed for members of log group 4 of thread 1
ORA-00312: online log 4 thread 1: '/fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo01.log'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
RFS[2]: Selected log 5 for thread 1 sequence 180 dbid 850194755 branch 974451523
Recovery of Online Redo Log: Thread 1 Group 5 Seq 180 Reading mem 0
Mem# 0: /fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo02.log
解决方法：
sql> select group#,status from v$standby_log;
GROUP# STATUS
---------- ----------
4 ACTIVE
5 ACTIVE
6 UNASSIGNED
7 UNASSIGNED
sql>
sql> col member for a60
GROUP# STATUS MEMBER
---------- ------- ------------------------------------------------------------
1 /fantlam/oracle/app/oracle/oradata/mmptdg/redo01.log
2 /fantlam/oracle/app/oracle/oradata/mmptdg/redo02.log
3 /fantlam/oracle/app/oracle/oradata/mmptdg/redo03.log
4 /fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo01.log
5 /fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo02.log
6 /fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo03.log
7 /fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo04.log
7 rows selected.
sql> alter database clear logfile group 4;
alter database clear logfile group 4
*
ERROR at line 1:
ORA-01156: recovery or flashback in progress may need access to files
sql> alter database recover managed standby database cancel;
Database altered.
sql> alter database clear logfile group 5;
sql> alter database clear logfile group 6;
sql> alter database clear logfile group 7;
sql>
查看告警日志
主库切换日志，备库日志无告警。
Media Recovery Log /archivelog/1_209_974451523.dbf
Media Recovery Waiting for thread 1 sequence 210 (in transit)
Recovery of Online Redo Log: Thread 1 Group 5 Seq 210 Reading mem 0
Mem# 0: /fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo02.log
Media Recovery Waiting for thread 1 sequence 211 (in transit)
RFS[9]: Selected log 4 for thread 1 sequence 211 dbid 850194755 branch 974451523
Thu May 10 09:41:37 2018
Archived Log entry 164 added for thread 1 sequence 210 ID 0x32ae65b9 dest 1:
Archived Log entry 165 added for thread 1 sequence 211 ID 0x32ae65b9 dest 1:
RFS[9]: Selected log 4 for thread 1 sequence 213 dbid 850194755 branch 974451523
RFS[7]: Selected log 5 for thread 1 sequence 212 dbid 850194755 branch 974451523
RFS[9]: Selected log 6 for thread 1 sequence 214 dbid 850194755 branch 974451523
Archived Log entry 166 added for thread 1 sequence 212 ID 0x32ae65b9 dest 1:
Archived Log entry 167 added for thread 1 sequence 213 ID 0x32ae65b9 dest 1:
Media Recovery Log /archivelog/1_211_974451523.dbf
Media Recovery Log /archivelog/1_212_974451523.dbf
Media Recovery Log /archivelog/1_213_974451523.dbf
Media Recovery Waiting for thread 1 sequence 214 (in transit)
Recovery of Online Redo Log: Thread 1 Group 6 Seq 214 Reading mem 0
Mem# 0: /fantlam/oracle/app/oracle/oradata/mmptdg/stdby_redo03.log
