利用rman构建physical standby指南

  之前整理过一篇利用数据库冷备份创建physical standby的文章，数据库的冷备需要停机，在生产环境中实用性不大，本将中将介绍如何利用rman热备来创建dataguard物理备库，这样主库只需要重启一次即可，大大提高了主库的高可用性！
环境介绍：
primary: rhel5.4 32位 192.168.227.20/24，db_unique_name: primary
standby: rhel5.4 32位 192.168.227.30/24，db_unique_name: standby
oracle版本： 10.2.0.1 32位企业版

一：standby服务器
1：主库上开启Forced Logging

SQL> alter database force logging;
Database altered.

2：在备库上创建密码文件，这里直接从主库复制到备库

[oracle@orcl ~]$ scp $ORACLE_HOME/dbs/orapworcl 192.168.227.30:/u01/app/oracle/product/10.2.0/db_1/dbs
[email protected]'s password:
orapworcl                                          100% 1536     1.5KB/s   00:00

3：主库上配置Standby Redo Log

SQL> select member from v$logfile;

MEMBER
---------------------------------------
/u01/app/oracle/oradata/orcl/redo03.log
/u01/app/oracle/oradata/orcl/redo02.log
/u01/app/oracle/oradata/orcl/redo01.log

SQL> !du -sh /u01/app/oracle/oradata/orcl/redo01.log
51M     /u01/app/oracle/oradata/orcl/redo01.log

SQL> alter database add standby logfile group 4
  2  '/u01/app/oracle/oradata/orcl/standby/standby04.log' size 50M;
Database altered.

SQL> SELECT GROUP#,THREAD#,SEQUENCE#,ARCHIVED,STATUS FROM V$STANDBY_LOG;

    GROUP#    THREAD#  SEQUENCE# ARC STATUS
---------- ---------- ---------- --- ----------
         4          0          0 YES UNASSIGNED
         5          0          0 YES UNASSIGNED
         6          0          0 YES UNASSIGNED

4.修改主库的初始化参数

SQL> show parameter db_name;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_name                              string      orcl
SQL> show parameter db_unique_name;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
db_unique_name                       string      primary

SQL> alter system set LOG_ARCHIVE_CONFIG='DG_CONFIG=(primary,standby)';
System altered.

SQL> alter system set log_archive_dest_1='LOCATION=/u01/arch/orcl valid_for=(all_logfiles,all_roles) db_unique_name=primary' scope=spfile;
System altered.

SQL> alter system set log_archive_dest_2='service=standby lgwr async valid_for=(online_logfiles,primary_role) db_unique_name=standby' scope=spfile;
System altered.

SQL> alter system set log_archive_dest_state_1=enable;
System altered.

SQL> alter system set log_archive_dest_state_2=enable;
System altered.

SQL> alter system set log_archive_format='%t_%s_%r.arc' scope=spfile;
System altered.

SQL> show parameter remote_login;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ---------
remote_login_passwordfile            string      EXCLUSIVE

SQL> alter system set log_archive_max_processes=30;
System altered.

SQL> alter system set fal_server=standby;
System altered.

SQL> alter system set fal_client=primary;
System altered.

SQL> alter system set standby_file_management=auto;
System altered.
SQL> !mkdir -p /u01/arch/orcl
SQL> shutdown immediate;
SQL> startup

5：配置主库的tnsnames.ora文件，备库需要同样的操作

[oracle@orcl ~]$ cat $ORACLE_HOME/network/admin/tnsnames.ora
# tnsnames.ora Network Configuration File: /u01/app/oracle/product/10.2.0/db_1/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.

primary =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.227.20)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = primary.herostart.com)
    )
  )

standby =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.227.30)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = standby.herostart.com)
    )
  )

6：在主库上准备备库需要的pfile和数据库备份文件，控制文件等

[oracle@orcl ~]$ mkdir -p /u01/backup/
SQL> create pfile='/u01/backup/initorcl.ora' from spfile;
File created.

[oracle@orcl ~]$ rman target /
RMAN> backup tag 'dg_20110909' format '/u01/backup/dg_%U' incremental level 0 database plus archivelog;

RMAN> backup format '/u01/backup/controlfile_%U' current controlfile for standby;

二：standby服务器

1：设置oracle_sid,配置tnsnames.ora

[oracle@orcl ~]$ export ORACLE_SID=orcl
[oracle@orcl ~]$ cat $ORACLE_HOME/network/admin/tnsnames.ora
primary =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.227.20)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = primary.herostart.com)
    )
  )

standby =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.227.30)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = standby.herostart.com)
    )
  )

2：在备库上复制主库备份出来的备份文件，并准备相关的目录 

[oracle@orcl ~]$ mkdir -p /u01/backup/
[oracle@orcl ~]$ scp -rp 192.168.227.20:/u01/backup/* /u01/backup/
[oracle@orcl ~]$ cp /u01/backup/initorcl.ora $ORACLE_HOME/dbs
[oracle@orcl ~]$ grep 'fal_' $ORACLE_HOME/dbs/initorcl.ora
*.fal_client='STANDBY'
*.fal_server='PRIMARY'
[oracle@orcl ~]$ grep 'log_archive_dest_'  $ORACLE_HOME/dbs/initorcl.ora  *.log_archive_dest_1='LOCATION=/u01/arch/orcl valid_for=(all_logfiles,all_roles) db_unique_name=standby'*.log_archive_dest_2='service=primary lgwr async valid_for=(online_logfiles,primary_role) db_unique_name=primary'*.log_archive_dest_state_1='ENABLE'*.log_archive_dest_state_2='ENABLE
[oracle@orcl ~]$ mkdir -p /u01/arch/orcl
[oracle@orcl ~]$ mkdir -p /u01/app/oracle/admin/orcl/{adump,bdump,cdump,dpdump,udump,pfile}
[oracle@orcl ~]$ mkdir -p /u01/app/oracle/oradata/orcl
[oracle@orcl ~]$ mkdir -p /u01/app/oracle/flash_recover_area/ORCL

3：将备库启动到mount状态

[oracle@orcl ~]$ sqlplus /nolog
SQL> conn /as sysdba
Connected to an idle instance.
SQL> startup nomount
ORACLE instance started.

4：使用rman对备库进行恢复

[oracle@orcl ~]$ rman target sys/123456@primary auxiliary /
Recovery Manager: Release 10.2.0.1.0 - Production on Thu Sep 15 16:08:34 2011
Copyright (c) 1982, 2005, Oracle.  All rights reserved.
connected to target database: ORCL (DBID=1287906064)
connected to auxiliary database: ORCL (not mounted)

RMAN> duplicate target database for standby nofilenamecheck;

5: 将备库置于应用redolog模式

[oracle@orcl ~]$ sqlplus /nolog
SQL> conn /as sysdba
Connected.
SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /u01/arch/orcl
Oldest online log sequence     47
Next log sequence to archive   49
Current log sequence           49

SQL> alter database recover managed standby database disconnect from session;
Database altered.

SQL> select SEQUENCE#,FIRST_TIME,NEXT_TIME,APPLIED from v$archived_log;

 SEQUENCE# FIRST_TIME          NEXT_TIME           APP
---------- ------------------- ------------------- ---
        47 2011-09-09:10:56:31 2011-09-09:10:57:51 YES

SQL> select member from v$logfile;
MEMBER--------------------------------------------------------------------------------/u01/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_3_773dso2v_.log/u01/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_2_773dsmpk_.log/u01/app/oracle/flash_recovery_area/STANDBY/onlinelog/o1_mf_1_773dsl9v_.log

可以在主库上进行日志切换，加快备库应用日志的速度！

[oracle@orcl ~]$ sqlplus /nolog
SQL> conn /as sysdba
Connected.
SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /u01/arch/orcl
Oldest online log sequence     47
Next log sequence to archive   49
Current log sequence           49
SQL> alter system switch logfile;
System altered.

SQL> alter system switch logfile;
System altered.

SQL> archive log list;
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            /u01/arch/orcl
Oldest online log sequence     48
Next log sequence to archive   50
Current log sequence           50

备库上再次查询：
SQL> select SEQUENCE#,FIRST_TIME,NEXT_TIME,APPLIED from v$archived_log;

 SEQUENCE# FIRST_TIME          NEXT_TIME           APP
---------- ------------------- ------------------- ---
        47 2011-09-09:10:56:31 2011-09-09:10:57:51 YES
        49 2011-09-09:10:57:54 2011-09-09:11:21:25 YES
        48 2011-09-09:10:57:51 2011-09-09:10:57:54 YES


SQL> select name,database_role from v$database;
NAME      DATABASE_ROLE
--------- ----------------
ORCL      PHYSICAL STANDBY

三：测试

1.在主库上创建表空间，建表

SQL> select name,database_role from v$database;

NAME      DATABASE_ROLE
--------- ----------------
ORCL      PRIMARY

SQL> create tablespace dg_test datafile
  2  '/u01/app/oracle/oradata/orcl/dg_test01.dbf'
  3  size 10M autoextend off;
Tablespace created.

SQL> create table dg01 as select * from dba_source;
Table created

SQL> alter system switch logfile;
System altered.

2.备库应用日志后以只读方式打开查看数据

SQL> alter database recover managed standby database cancel;
Database altered

SQL> alter database open read only;
Database altered.

SQL> select type from dg01 where rownum <= 3;

TYPE
------------
PACKAGE
PACKAGE
PACKAGE

SQL> select count(*) from dg01;

  COUNT(*)
----------
    292428

3：从新将备库置于应用日志模式

[oracle@orcl ~]$ sqlplus /nolog
SQL> conn /as sysdba
Connected.
SQL> shutdown immediate;
SQL> startup nomount；
SQL> alter database mount standby database;
Database altered.
SQL> alter database recover managed standby database disconnect from session;
Database altered.

备注：本文参考oracle10g 手册，相关的参数含义可以在手册上查找！