设置Oracle Dataguard的侦听器

Question

我设置了一个Oracle 12c Dataguard配置。为了构建备用数据库，我使用了RMAN命令，它需要静态侦听器配置。

关于HOSTNAMEA和HOSTNAMEB的tnsname.ora是相同的：

BR =   (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTNAMEA)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SID = BR)
    )   )

BR_STBY =   (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTNAMEB)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SID = BR)
    )   )

listener.ora HOSTNAMEA：

    SID_LIST_LISTENER =
        (SID_DESC =
          (GLOBAL_DBNAME = BR_DGMGRL)
          (ORACLE_HOME = /opt/oracle/product/12200/dbhome_1)
          (SID_NAME = BR)
        )

    LISTENER =
      (DESCRIPTION_LIST =
        (DESCRIPTION =
          (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTNAMEA)(PORT = 1521))
          (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
        )
  )

listener.ora HOSTNAMEB：

SID_LIST_LISTENER =
    (SID_DESC =
      (GLOBAL_DBNAME = BR_STDBY_DGMGRL)
      (ORACLE_HOME = /opt/oracle/product/12200/dbhome_1)
      (SID_NAME = BR)
    )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTNAMEB)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
  )

此配置使用静态侦听器配置。例如，应用程序如何知道数据库已经从HOSTNAMEA切换到HOSTNAMEB？我应该使用动态侦听器注册吗？配置应该是什么样的？

Answer 1

您应该在客户端计算机中有一个TNS条目，类似于连接到数据保护环境的以下内容。

BR =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTA)(PORT = 1521))
      (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTB)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = BR)
    )
  )

BR_STBY =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTA)(PORT = 1521))
      (ADDRESS = (PROTOCOL = TCP)(HOST = HOSTB)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = BR_STBY)
    )
  )

您还应该按照它们的角色配置数据库服务--主要的或备用的，如下所示(如果您使用的是网格基础设施)。

srvctl add service -d BR  -s BR -l PRIMARY -m BASIC -e SELECT -w 1 -z 180 
srvctl add service -d BR  -s BR_STBY -l PHYSICAL_STANDBY –m BASIC –e SELECT –w 1 –z 180
srvctl start service -s BR -s BR

如果您没有使用网格基础设施，那么(作为SYSDBA在主)-

SQL>exec dbms_service.create_service(service_name => 'BR', network_name => 'BR', failover_method => 'BASIC', failover_type => 'SELECT', failover_retries => 10, failover_delay => 1);
SQL> exec dbms_service.create_service(service_name => 'BR_STBY', network_name => 'BR_STBY', failover_method => 'BASIC', failover_type => 'SELECT', failover_retries => 10, failover_delay => 1);
SQL> create or replace trigger MANAGE_SERVICES
  after startup on database
declare
  db_role varchar2(16);
  db_mode varchar2(20);
begin
  select database_role, open_mode into db_role, db_mode from v$database;
  if db_role = 'PRIMARY' then
    dbms_service.start_service('BR');
    dbms_service.stop_service('BR_STBY');
  elsif (db_role = 'PHYSICAL STANDBY') and (db_mode = 'READ ONLY') then
    dbms_service.start_service('BR_STBY');
    dbms_service.stop_service('BR');
  else
    dbms_service.stop_service('BR');
    dbms_service.stop_service('BR_STBY');
  end if;
end;
/
SQL>

根据需要修改上述示例中使用的属性，并参考Oracle文档获取详细信息。