Oracle DataGuard主备切换之自动切换

今天主要介绍使用DG_broker工具管理切换DG主备。

1、设置primary和standby启动时参数文件为spfile

SQL>  show parameter spfile;

2、设置DG_BROKER_START为TRUE

将主备库的dg_broker_start的VALUE设置为true。

SQL>alter system set dg_broker_start=true scope=both;
SQL>! ps -ef|grep dmon
SQL>show parameter dg_broker_start；
SQL>SELECT d.DBID,
d.DB_UNIQUE_NAME,
d.FORCE_LOGGING,
d.FLASHBACK_ON,
d.FS_FAILOVER_STATUS,
d.FS_FAILOVER_CURRENT_TARGET,
d.FS_FAILOVER_THRESHOLD,
d.FS_FAILOVER_OBSERVER_PRESENT,
d.FS_FAILOVER_OBSERVER_HOST
 FROM v$database d;

3、配置监听

需要在listener.ora静态添加一个service_name为db_unique_name_DGMGRL.db_domain的注册。这个service_name会在DGMGRL重启数据库的时候用到。通过DGMGRL重启数据库时DMON进程会先将数据库关闭，然后DGMGRL用此service_name通过listener连接到数据库，发出启动命令。tnsnames.ora主备库保持一致。
主库：

[oracle@standbynode ~]$ vi /u01/app/oracle/product/11.2.0/db_1/network/admin/listener.ora

# listener.ora Network Configuration File: u01/oracle/product/11.2.0/db_1/network/admin/listener.ora
# Generated by Oracle configuration tools.

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS_LIST =
        (ADDRESS = (PROTOCOL = TCP)(HOST = standbynode)(PORT = 1521))
      )
    )
  )

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (GLOBAL_DBNAME=orcl11gdg)
      (ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1)
      (SID_NAME = orcl11g)
    )
    (SID_DESC =
      (GLOBAL_DBNAME = orcl11gdg_DGMGRL.lhr.com)
      (ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1)
      (SID_NAME = orcl11g)
    )
  )

ADR_BASE_LISTENER = /u01/app/oracle
LOGGING_LISTENER = OFF
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER = ON

[oracle@standbynode ~]$ vi /u01/app/oracle/product/11.2.0/db_1/network/admin/tnsnames.ora

tnsorcl11g =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.249)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl11g)
    )
  )

tnsorcl11gstandby =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.250)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl11g)
    )
  )
tns_orcl11g_DGMGRL =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.249)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = orcl11g_DGMGRL.lhr.com)

    )

  )
tns_orcl11gstandby_DGMGRL =

  (DESCRIPTION =

    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.250)(PORT = 1521))

    (CONNECT_DATA =

      (SERVER = DEDICATED)

      (SERVICE_NAME = orcl11gdg_DGMGRL.lhr.com)

    )

备库：

[oracle@primarynode ~]$ vi /u01/app/oracle/product/11.2.0/db_1/network/admin/listener.ora

# listener.ora Network Configuration File: u01/app/oracle/product/11.2.0/db_1/network/admin/listener.ora
# Generated by Oracle configuration tools.

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
      (ADDRESS = (PROTOCOL = TCP)(HOST = primarynode)(PORT = 1521))
    )
  )
SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (GLOBAL_DBNAME=orcl11g_DGMGRL.lhr.com)
      (ORACLE_HOME = /u01/app/oracle/product/11.2.0/db_1)
      (SID_NAME = orcl11g)
    )
  )
ADR_BASE_LISTENER = /u01/app/oracle

[oracle@primarynode ~]$ vi /u01/app/oracle/product/11.2.0/db_1/network/admin/tnsnames.ora

  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.249)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = orcl11g)
    )
  )
tnsorcl11gstandby =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.250)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = orcl11g)
    )
  )
tns_orcl11g_DGMGRL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.249)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl11g_DGMGRL.lhr.com)
    )
  )
tns_orcl11gstandby_DGMGRL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.59.250)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl11gdg_DGMGRL.lhr.com)
    )

  )

4、dgmgrl中配置broker并启用

[oracle@primarynode ~]$ dgmgrl
DGMGRL> connect sys/password@tns_orcl11gdg_DGMGRL
DGMGRL> show configuration

#如果之前有配置，请先移除
DGMGRL> REMOVE CONFIGURATION;
--查看参数文件的状态
DGMGRL> SHOW CONFIGURATION;
#创建新的参数文件CONFIGURATION：
DGMGRL> create configuration 'fsf_orcl11g_lhr' as primary database is 'orcl11gdg' connect identifier is tns_orcl11gstandby_DGMGRL; 
--添加备库：
DGMGRL> add database 'orcl11g' as connect identifier is tns_orcl11g_DGMGRL maintained as physical;
--启用参数文件：
DGMGRL> ENABLE CONFIGURATION;
--查看参数文件的状态
DGMGRL> SHOW CONFIGURATION;
--启用备库
DGMGRL> ENABLE DATABASE 'orcl11g'

5、切换主备库

DGMGRL> switchover to orcl11g

6、验证主备是否切换成功

主备库都执行

SQL> set lines 999
SQL> select database_role,open_mode from v$database;

在上图中我们可以看到主备已经完成切换。当然也可以切换保护模式，大家自行测试，这里我再不演示。
重新调至最大可用模式：

DGMGRL> EDIT DATABASE 'orcl11g' SET PROPERTY 'LogXptMode'='ASYNC';
DGMGRL> EDIT CONFIGURATION SET PROTECTION MODE AS MAXPERFORMANCE;

遇到oracle DGMGRL ORA-16603报错的解决方法(DG Broker)

备库执行：

[oracle@primarynode dbs]$cd $ORACLE_HOME/dbs
[oracle@primarynode dbs]$rm -rf dr*

SQL> alter system set dg_broker_start=false;
SQL> alter system set dg_broker_start=true;
SQL> show parameter dg_broker

参考链接：

https://blog.csdn.net/tuning_optmization/article/details/79235281

手动切换可以看我上一篇文章：

https://mp.weixin.qq.com/s/f9LB6rte7UrlcfCyO9pvgA

文中的概念来源于互联网，如有侵权，请联系我删除。

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