oracle 11gr2 dataguard （一）fast_start_failover
此功能实现在主down掉时，将备提升为住，实现业务不间断
前提条件:
主从数据库都要使用spfile:
数据同步的级别:
lgwr sync affirm
主从数据库都要运行在最高可用模式:
alter database set standby database to maximize availability;
select protection_mode,database_role,protection_level from v$database;
主从数据库都要有standby联机日志:
select * from v$standby_log;
从库要有standby日志的归档路径:
SQL> alter system set log_archive_dest_3='location=/home/oracle/aux1_stdlog VALID_FOR=(STANDBY_LOGFILES,STANDBY_ROLE) DB_UNIQUE_NAME=orcl'
主从数据库都要启动数据库的闪回功能:
select flashback_on from v$database;
如果显示为NO
关库然后执行
shutdown abort;
startup mount;
alter system set flash_back on;
环境检查完毕下面开始操作
1、主从数据库都要配置:
local_listener='连接自身的服务命名'
--on primary(130)
SQL> alter system set local_listener='to_130';
--on standby(140)
SQL> alter system set local_listener='to_140';
2、
查看归档终点是否有异常:
#col dest_name for a30
#col error for a20
#select dest_name,status,target,archiver,error,process from v$archive_dest;
3、-- on primary,standby
SQL> alter system set dg_broker_start=true;
4、-- on primary,standby
$ dgmgrl
DGMGRL> connect sys/oracle@to_130 （程序在哪启动都可，但要链接到主库）
创建中介配置:
DGMGRL> create configuration 'testBroker' as primary database is 'orcl'connect identifier is to_130
DGMGRL> SHOW DATABASE VERBOSE orcl
在中介配置中添加备用数据库:
DGMGRL> add database 'orcl2' as connect identifier is orcl2 maintained as physical;
查看broker配置状态:
DGMGRL> show configuration verbose;
启动broker配置:
DGMGRL> enable configuration
DGMGRL> ENABLE FAST_START FAILOVER
修改快速故障转移的延迟时间(默认为30秒 ):
DGMGRL> edit configuration set property FastStartFailoverThreshold=120;
DGMGRL> show configuration
启动Observer监视器(on standby)
DGMGRL> start observer;
启动之后，该前台进程不会退出，会一直挂在这。 直到从其他窗口关闭!
在新的窗口再启动一个dgmgrl,查看快速转移配置:
DGMGRL> show configuration verbose;
DGMGRL> show database verbose orcl;
DGMGRL> show database verbose orcl2;
在数据库中查看快速转移状态:
-- on primary
SQL> col FS_FAILOVER_OBSERVER_HOST for a20
SQL> select fs_failover_observer_present,fs_failover_observer_host,fs_failover_threshold from v$database;
FS_FAIL FS_FAILOVER_OBSERVER FS_FAILOVER_THRESHOLD
------- -------------------- ---------------------
YES alvin 0
-- on standby
SQL> col FS_FAILOVER_OBSERVER_HOST for a20
SQL> select fs_failover_observer_present,fs_failover_observer_host,fs_failover_threshold from v$database;
FS_FAIL FS_FAILOVER_OBSERVER FS_FAILOVER_THRESHOLD
------- -------------------- ---------------------
YES alvin 30
--testing
--on primary
sql>shutdown abort;
-- wait one minute
--on old_standby change priary
DGMGRL> start observer;
Observer started
15:19:11.95 Monday, March 12, 2012
Initiating Fast-Start Failover to database "orcl"...
Performing failover NOW, please wait...
Failover succeeded, new primary is "orcl2"
15:19:18.67 Monday, March 12, 201
客户端配置网络,使其支持透明故障转移:
配置客户端TAF:
TAF=
(DESCRIPTION=
(LOAD_BALANCE=on)
(FAILOVER=on)
(ADDRESS=(PROTOCOL=tcp) (HOST=10.10.10.130) (PORT=1521))
(ADDRESS=(PROTOCOL=tcp) (HOST=10.10.10.140) (PORT=1521))
(CONNECT_DATA=
(SERVICE_NAME=orcl)
(FAILOVER_MODE=
(TYPE=select)
(METHOD=basic))))