1.standby database 正常的打开与关闭


1.1  针对 physical standby
打开：
--打开数据库
SQL>startup; 
-- 开启 mgr 进程  
SQL>ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE disconnect from session;  ( physical standby )


关闭：
-- 关闭 mgr 进程
SQL>ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL;
-- 正常关闭数据库
SQL> shutdown immediate;


1.2 针对 logical standby
-- 开启 mgr 进程
SQL>ALTER DATABASE START LOGICAL STANDBY APPLY IMMEDIATE;     
-- 关闭 mgr 进程
SQL>ALTER DATABASE STOP LOGICAL STANDBY APPLY;




2. 查看数据库角色与保护模式


SQL> select protection_mode, protection_level, database_role role, switchover_status from v$database;




3.查询每个standby 的状态：
-- 主库执行
SQL> SELECT DEST_ID, STATUS,APPLIED_SCN FROM V$ARCHIVE_DEST WHERE TARGET='STANDBY';
 
  DEST_ID STATUS    APPLIED_SCN
---------- --------- -----------
         2 VALID         1818069


4. 检查redo 传送情况


-- 备库查看当前 log sequence 
SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     41
Next log sequence to archive   0
Current log sequence           41
-- 主库日志切换
SQL> alter system switch logfile;
System altered.
-- 备库查看当前 log sequence ，如果 log sequence 有变化说明传输没有问题。
SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     41
Next log sequence to archive   0
Current log sequence           42


5. 检查 mrp 应用情况
--备库执行
SQL> SELECT THREAD#, SEQUENCE#, FIRST_CHANGE#,NEXT_CHANGE#,APPLIED FROM V$ARCHIVED_LOG;


   THREAD#  SEQUENCE# FIRST_CHANGE# NEXT_CHANGE# APPLIED
---------- ---------- ------------- ------------ ---------
         1         24       1449716      1451135 YES
         1         26       1476706      1481494 YES
         1         25       1451135      1476706 YES
         1         27       1481494      1491422 YES
         1         29       1524315      1547524 YES


6.  查询archived log 的历史信息：（主备都执行，对比是否相同）
SQL> SELECT THREAD#, SEQUENCE#, FIRST_CHANGE#, NEXT_CHANGE# FROM V$LOG_HISTORY;


7.  查询DG的日志信息，这些日志信息可以写入alert log 或者进程的trace 文件
SQL> set pagesize 200
SQL> SELECT MESSAGE FROM V$DATAGUARD_STATUS;
MESSAGE
------------------------------------------
ARC0: Archival started
ARC1: Archival started
ARC2: Archival started
ARC2: Becoming the 'no FAL' ARCH
ARC1: Becoming the heartbeat ARCH
ARC1: Becoming the active heartbeat ARCH
ARC3: Archival started