dataguard中的ora-00312

ora-00322:log 1of thread 1 is not current copy
ora-00312:online log 1thread 1:'opt/oracle/oradata/oradb/REDO02.LOG'

解决办法如下：
1. shutdown  immediate;
2. startup mount;
3. alter database clear logfile 'opt/oracle/oradata/oradb/REDO02.LOG';
4. alter database open;
5. select status from v$instance;
看到Oracle可以正常启动了；