1. 主数据库或者其他备库的归档日志还存在的恢复方式：归档直接恢复方式

   
   

   1.1 copy 主库上的归档日志至备库，如果ASM磁盘先通过rman方式copy至文件系统

   RMAN>copy archivelog '+data/orcl/ARCHIVELOG/2020_03_24/thread_1_seq_328729.4592.939510649' to'/home/oracle/archivelog/thread_1_seq_328729.4592.939510649';
   

    1.2 备机注册archivelog到数据库control file中

   RMAN> catalog start with '/home/oracle/archivelog';

    1.3 启动备机执行recover，执行实时应用日志

   ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE DISCONNECT FROM SESSION;

    1.4 确认日志归档应用已启动，至此DG已恢复同步

    select process,status,client_process,sequence#,block# from v$managed_standby;

   
   

2. 主数据库或者其他备库的归档日志已丢失的恢复方式：增量备份恢复方式

   1.备份备库spfile文件
   SQL> create pfile='/home/ora/pfile_standby.ora' from spfile;
   

   2、查看当前备库scn
   SQL> select to_char(current_scn) from v$database;
   
   TO_CHAR(CURRENT_SCN)
   ----------------------------------------
   145215070

   3、查看缺失的archivelog
   SQL> select * from v$archive_gap;
   
   4、在主库执增量备份

RMAN> run
 {
 allocate channel d1 type disk;
 allocate channel d2 type disk;
backup as compressed backupset incremental from SCN 145215070 database format '/home/oracle/full_db_%d_%T_%s.bak' include current controlfile for standby filesperset=5 tag 'FOR STANDBY';
release channel d1;
release channel d2;
}

        5、将备份传至备库
        scp full_db_orcl_xxxx_*.bak 192.168.1.100:~/xxxx_recover/ 
        6、注册备份文件，恢复备库

RMAN> catalog start with '/home/ora/20150523_recover';

RMAN> 

run
{
allocate channel d1 type disk;
allocate channel d2 type disk;
restore standby controlfile to '/home/oracle/control01.ctl';
recover database noredo;
release channel d1;
release channel d2;

}

        7、关闭备库，将恢复出来的control01.ctl覆盖备库控制文件
        $ cp control01.ctl /oradata/orcl/standby.ctl
        8、启动备库至mount状态
        SQL> startup mount

        9、查看gap
        SQL> select * from v$archive_gap;
        
        10、开启备库recover模式
        SQL> alter database recover managed standby database disconnect from session;
        Media recovery complete.