MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY MANAGED REAL TIME APPLY 11 rows selected.
如果是没有启用日志的实时应用，recovery_mode显示的是MANAGED SQL> alter database recover managed standby database disconnect; Database altered.
SQL> select RECOVERY_MODE from v$archive_dest_status; RECOVERY_MODE
----------------------- MANAGED MANAGED MANAGED MANAGED MANAGED MANAGED MANAGED MANAGED MANAGED MANAGED MANAGED 11 rows selected.
在备机检查当前日志文件应用的情况，使用如下语句 SQL> col name for a50 SQL> set linesize 140
SQL> select name,sequence#,archived,applied from v$archived_log order by sequence#; NAME SEQUENCE# ARC APP -------------------------------------------------- ---------- --- ---
/u01/app/oracle/archdest/1_2_749662393.dbf 2 YES YES /u01/app/oracle/archdest/1_3_749662393.dbf 3 YES YES /u01/app/oracle/archdest/1_4_749662393.dbf 4 YES YES /u01/app/oracle/archdest/1_5_749662393.dbf 5 YES YES /u01/app/oracle/archdest/1_6_749662393.dbf 6 YES YES /u01/app/oracle/archdest/1_7_749662393.dbf 7 YES YES /u01/app/oracle/archdest/1_8_749662393.dbf 8 YES YES /u01/app/oracle/archdest/1_9_749662393.dbf 9 YES YES /u01/app/oracle/archdest/1_10_749662393.dbf 10 YES YES 9 rows selected.
查看dataguard 备机是否启用了日志应用，如果看不到mrp进程，说明没有应用日志。 SQL> select process,status from v$managed_standby; PROCESS STATUS --------- ------------ ARCH CONNECTED ARCH CONNECTED RFS IDLE RFS IDLE RFS IDLE
2.oracle dataguard 数据库保护模式的变更
检查当前数据库是处在那种角色，以及现在使用的保护模式，使用如下的查询语句 在主机 primary 192.168.1.90，执行语句
SQL>select DATABASE_ROLE,PROTECTION_MODE,PROTECTION_LEVEL from v$database;
DATABASE_ROLE PROTECTION_MODE PROTECTION_LEVEL ---------------- -------------------- --------------------
PRIMARY MAXIMUM PERFORMANCE MAXIMUM PERFORMANCE 在备机 standby 192.168.1.91，执行语句
SQL> select DATABASE_ROLE,PROTECTION_MODE,PROTECTION_LEVEL from v$database;
DATABASE_ROLE PROTECTION_MODE PROTECTION_LEVEL ---------------- -------------------- --------------------
PHYSICAL STANDBY MAXIMUM PERFORMANCE MAXIMUM PERFORMANCE
升级oracle数据库的保护模式 （MAXIMUM PERFORMANCE-->max availability-->max protection），
如果要升级oracle数据库的保护模式，必须在mount状态下来执行命令 在主机 primary 192.168.1.90，执行如下操作（以下操作只需要在主机操作） SQL> shutdown immediate Database closed. Database dismounted. ORACLE instance shut down. SQL> startup mount ORACLE instance started.
Total System Global Area 218103808 bytes Fixed Size 1218604 bytes Variable Size 71305172 bytes Database Buffers 142606336 bytes Redo Buffers 2973696 bytes Database mounted.
SQL> alter database set standby database to maximize availability; Database altered.
SQL> alter database open; Database altered.
SQL> select DATABASE_ROLE,PROTECTION_MODE,PROTECTION_LEVEL from v$database;
DATABASE_ROLE PROTECTION_MODE PROTECTION_LEVEL ---------------- -------------------- --------------------
PRIMARY MAXIMUM AVAILABILITY MAXIMUM AVAILABILITY
在备机 standby 192.168.1.91，执行语句，确认修改是否生效 SQL> show parameter db_un
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------ db_unique_name string standby
SQL> select DATABASE_ROLE,PROTECTION_MODE,PROTECTION_LEVEL from v$database;
DATABASE_ROLE PROTECTION_MODE PROTECTION_LEVEL ---------------- -------------------- --------------------
PHYSICAL STANDBY MAXIMUM AVAILABILITY MAXIMUM AVAILABILITY 注：如果降级数据库的保护模式，直接操作就可以，不需要到mount状态。
3.oracle dataguard 数据库切换（switchover）操作测试
切换过程中，主机会首先切换成备机，也就是在同一时间点，在dataguard 配置中有两台备机的存在
在主机 primary 192.168.1.90，执行如下操作
SQL> select database_role,switchover_status from v$database; DATABASE_ROLE SWITCHOVER_STATUS ---------------- -------------------- PRIMARY SESSIONS ACTIVE
SQL> alter database commit to switchover to physical standby; Database altered. SQL> shutdown immediate
ORA-01507: database not mounted ORACLE instance shut down.
SQL> startup mount ORACLE instance started.
Total System Global Area 218103808 bytes Fixed Size 1218604 bytes Variable Size 71305172 bytes Database Buffers 142606336 bytes Redo Buffers 2973696 bytes Database mounted.
SQL> recover managed standby database disconnect; Media recovery complete.
SQL> select database_role,switchover_status from v$database;
DATABASE_ROLE SWITCHOVER_STATUS ---------------- -------------------- PHYSICAL STANDBY NOT ALLOWED
在备机 standby 192.168.1.91，执行如下语句，完成角色转换 SQL> select database_role,switchover_status from v$database; DATABASE_ROLE SWITCHOVER_STATUS ---------------- -------------------- PHYSICAL STANDBY TO PRIMARY
SQL> alter database commit to switchover to primary; Database altered.
SQL> select database_role,switchover_status from v$database; DATABASE_ROLE SWITCHOVER_STATUS