Oracle11gDataguard物理备库配置系列文档Oracle11gDataguard物理备库配置(一)之duplicate创建Oracle11gDataguard物理备库配置(二)之ActiveDataguar..
Oracle 11g Dataguard 物理备库配置系列文档
Oracle 11g Dataguard 物理备库配置(五)之broker switchover测试
Oracle 11g Dataguard 物理备库配置(六)之broker fastfailover测试
Oracle 11g Dataguard 配置学习小结
本文采用Oracle 11g Dataguard broker fastfailover测试
Oracle 11g Dataguard fast failover配置,香港服务器租用,需要主备数据库开启闪回功能,闪回功能开启本文略过。
闪回开启需要启动到mount状态时,主备库的监听不要随意关闭。
1. dgmgrl查看主备库状态
$ dgmgrl sys/oracle
DGMGRL for Linux: Version 11.2.0.3.0 - 64bit Production
Copyright (c) 2000, 2009, Oracle. All rights reserved.
欢迎使用 DGMGRL, 要获取有关信息请键入 "help"。
已连接。
DGMGRL> show configuration;
配置 - dgorcldb
保护模式: MaxPerformance
数据库:
orcl - 主数据库
slave - 物理备用数据库
快速启动故障转移: DISABLED
配置状态:
SUCCESS
#快速启动故障转移是不可用状态。
#查看故障转移情况,虚拟主机, DISABLED没有启用。
DGMGRL> show fast_start failover
快速启动故障转移: DISABLED
阈值: 30 秒
目标: (无)
观察程序: (无)
滞后限制: 30 秒
关闭主数据库: TRUE
自动恢复: TRUE
可配置的故障转移条件
健康状况:
Corrupted Controlfile YES
Corrupted Dictionary YES
Inaccessible Logfile NO
Stuck Archiver NO
Datafile Offline YES
Oracle 错误条件:
(无)
2. 启动快速启动故障转移
DGMGRL> enable fast_start failover;
3. 启动快速启动故障转移observer观察程序
DGMGRL> start observer;
说明:start observer后,观察程序不会在后台运行,就在前台显示。
在实际使用过程中,需要单独在服务器上启动,在后台自动运行,不能关闭,否则主备库就无法自动监控运行状态。
就无法使用快速启动故障转移功能。
4. 在另一个窗口执行查看
$ dgmgrl sys/oracle
DGMGRL> show fast_start failover;
快速启动故障转移: ENABLED
阈值: 30 秒
目标: slave
观察程序: master
滞后限制: 45 秒
关闭主数据库: TRUE
自动恢复: TRUE
可配置的故障转移条件
健康状况:
Corrupted Controlfile YES
Corrupted Dictionary YES
Inaccessible Logfile NO
Stuck Archiver NO
Datafile Offline YES
Oracle 错误条件:
(无)
DGMGRL> show configuration
配置 - dgorcldb
保护模式: MaxPerformance
数据库:
slave - 主数据库
orcl - (*) 物理备用数据库
快速启动故障转移: ENABLED
配置状态:
SUCCESS
至此dgmgrl 配置的fast_start failover已经配置好,下面模拟故障切换过程。
可以通过shutdown abort模拟数据库意外垮掉的情况,香港空间,
注1:主库shutdown immediate是不会启动fast start failover功能的。
注2:oracle 11g dataguard fast start failover切换不需要主备库运行在最大可用模式。
5. 模拟测试主库意外垮掉
1)主库上:
$ sqlplus / as sysdba;
SQL> shutdown abort;
观察器显示日志:显示执行主备切换过程

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