备库alert日志如下：
Errors in file /data/app/oracle/diag/rdbms/standby/orcl/trace/orcl_m000_31006.trc:
ORA-00313: open failed for members of log group 3 of thread 1
ORA-00312: online log 3 thread 1: '/data/oradata/orcl/redo03.log'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 7
并且 /data/oradata/orcl/ 目录下并无 online redo log存在。
解决办法：
备库修改参数
alter system set log_file_name_convert='/data/oradata/orcl','/data/oradata/orcl' scope=spfile ;
然后重启备库。