stream更加丰富,主要是应用层面的数据共享。前一段主要进行了rac的环境搭建,这两天在虚拟机上进行了dataguard环境搭建和测试,
rac,dataguard,stream被认为是Oracle的高可用的三架马车。
三架马车各有侧重:
rac主要解决了单节点故障,实现负载均衡,也实现了高性能。常用于24x7的商业应用。
dataguard用冗余的方式实现高可用的,解决容灾。
stream更加丰富,主要是应用层面的数据共享。
前一段主要进行了rac的环境搭建,这两天在虚拟机上进行了dataguard环境搭建和测试,开始想对之前的rac作为primary ,但是一直没有成功。还是一步步从简单的开始,从单实例来做,创建一个单实例的数据库,在同一台机器上搭建一个standby数据库。将自己的搭建步骤整理写出来,加深印象,供以后搭建参考,搭建的难点在于参数文件的配置。
环境:
操作系统:RedHat 4 32位 2.6.9-89.ELsmp
数据库版本:oracle 10g 10.2.0.1
已经有一个单实例的数据库了。
我是参考三思笔记搭建的,数据库名字直接用上面的名字了。下面所指的主数据库,primary数据库都是指jssweb, standby数据库指jsspdg。
我的数据库路径是
oracle_home=/usr/oracle/product/10.2.0/db_1
ORACLE_BASE=/usr/oracle
文件路径是:/usr/oracle/oradata/数据库名字/数据文件,控制文件,日志文件和归档日志文件。
搭建步骤:
1、确定primary数据库是归档模式
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination /usr/oracle/oradata/jssweb
Oldest online log sequence 34
Next log sequence to archive 36
Current log sequence 36
如果非归档模式
先设置归档位置
参看参数
SQL> show parameter archive log;
NAME TYPE VALUE
------------------------------------ ---------------------- ------------------------------
archive_lag_target integer 0
log_archive_config string DG_CONFIG=(jssweb,jsspdg)
log_archive_dest string
log_archive_dest_1 string LOCATION=/usr/oracle/oradata/j
ssweb VALID_FOR=(ALL_LOGFILES,
ALL_ROLES) DB_UNIQUE_NAME=jssw
eb
如果没有设置归档位置,先暂时设置一个归档位置,,再重新启动数据为归档模式
SQL> alter system set log_archive_dest_1='LOCATION=/usr/oracle/oradata/jssweb'
然后
SQL> shutdown immediate
……
SQL> startup mount
SQL> alter database archivelog;
SQL> alter database open;
2、先确定primary数据库是FORCED LOGGING模式,目的是所有ddl语句都写redo log,及时是有nologging限制的ddl语句。
SQL> alter database force logging;
alter database force logging
*
ERROR at line 1:
ORA-12920: database is already in force logging mode
说明已经是FORCED LOGGING
3、创建standby数据库的文件夹。主要是standby和primary的启动参数文件需要用。
用oracle用户
在/usr/oracle/admin下创建jsspdg文件夹
在/usr/oracle/admin/jsspdg/下创建adump bdump cdump dpdump pfile udump这些文件夹。
4、创建standby的控制文件,控制文件名直接用control01.ctl
在主primary数据库中创建
登录主数据库
SQL> alter database create standby controlfile as '/usr/oracle/oradata/jsspdg/control01.ctl';

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