诊断：MRP0: Background Media Recovery terminated with error 1111

表现：

灾备环境，无法继续应用日志。

日志：

MRP0: Background Media Recovery terminated with error 1111

Fri Jan 18 15:55:25 2019
Errors in file /oracle/diag/rdbms/orcldg/ORCL/trace/ORCL_dbw0_67731.trc:
ORA-01186: file 28 failed verification tests
ORA-01157: cannot identify/lock data file 28 - see DBWR trace file
ORA-01111: name for data file 28 is unknown - rename to correct file
ORA-01110: data file 28: '/oracle/product/11g/db/dbs/UNNAMED00028'
File 28 not verified due to error ORA-01157
MRP0: Background Media Recovery terminated with error 1111
Errors in file /oracle/diag/rdbms/orcldg/ORCL/trace/ORCL_pr00_144635.trc:
ORA-01111: name for data file 28 is unknown - rename to correct file
ORA-01110: data file 28: '/oracle/product/11g/db/dbs/UNNAMED00028'
ORA-01157: cannot identify/lock data file 28 - see DBWR trace file
ORA-01111: name for data file 28 is unknown - rename to correct file
ORA-01110: data file 28: '/oracle/product/11g/db/dbs/UNNAMED00028'

解决：

-- 将备库的standby_file_management参数修改为手动管理模式
SQL> alter system set standby_file_management='MANUAL' scope=both;

System altered.

-- 把UNNAMED数据文件放到正确路径
SQL> alter database create datafile '/oracle/product/11g/db/dbs/UNNAMED00028' as '/oradata/orcl/datafile/tbs_orcl.256.908366191';

Database altered.

-- 将备库的standby_file_management参数修改回自动模式
SQL> ALTER SYSTEM SET STANDBY_FILE_MANAGEMENT=AUTO scope=both;