对于基于生产环境下的数据库的版本升级或者测试新的应用程序的性能及其影响，备份恢复等等，我们可以采取从生产环境以克隆的方式将其克隆到本地而不影响生产数据库的正常使用。实现这个功能我们可以借助rman duplicate方式以及其简单的方式来完成。duplicate方式不同于OS级别的备份，它会为辅助数据库(克隆出来的数据库)生成一个新的dbid，而能够同时将目标数据库(原数据库)与辅助数据库注册到同一个恢复目录。本文描述了使用rman duplicate实现异机数据库克隆。
1、RMAN支持的duplicate类型
支持基于备份的duplicate方式，其中该方式又分为连接到target DB与不连接target DB，不连接target DB又分为连接到catalog与不连接catalog
支持基于活动数据库的duplicate方式。更多关于duplicate的描述及duplicate步骤，请参考:基于RMAN的同机数据库克隆
这两种方式可以使用下面的图示简要描述。
From Active DB
--------------
| With recovery catalog connection
Duplicate | |--------------------------------
------------| Without target conenction |
| |----------------------------|
| | |
--------------| |-------------
From Backups | Without recovery catalog connection
|-----------------------------
With target connection
2、RMAN异机恢复示意图
下面的图示是没有连接到target DB，也没有连接到recover catalog方式。基于这种方式实现duplicate，应指定备份文件所在的位置。
本文下面所演示的试验也是基于该方式，在演示的过程中，磁盘路径，目录，数据文件使用了相同的位置与文件名。
对于不同位置的duplicate情形，需要对文件位置进行转换，可参考: RMAN 数据库克隆文件位置转换方法
3、实战RMAN异机克隆
--环境:
--目标数据库: 192.168.7.25/sybo3 /u01/database/sybo3 主机名:linux3
--辅助数据库: 192.168.7.26/sybo3 /u01/database/sybo3 主机名:linux4 目标数据库与辅助数据库使用相同的文件位置
--说明：
--本次演示使用了备份文件，没有连接到catalog，也没有连接到target DB。
--对于下面描述过程中，如创建参数文件，密码文件，监听等等有不甚了解的，可参考下面链接中有关文章的描述。
--http://blog.csdn.net/robinson_0612/article/category/827734 (体系结构相关)
--http://blog.csdn.net/robinson_0612/article/category/828434 (网络配置相关)
[oracle@linux3 database]$ cat /etc/issue
Enterprise Linux Enterprise Linux Server release 5.5 (Carthage)
Kernel \r on an \m
SQL> select * from v$version where rownum<2;
BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
a、备份及ftp目标数据库
--目标数据库存在的表及其内容，用于后续验证
SQL> select * from t;
NAME ACTION
---------- --------------------
Robinson Transfer DB
Jackson Transfer DB by rman
--下面备份目标数据库并ftp到辅助数据库所在的主机
$ export ORACLE_SID=sybo3
$ rman target /
RMAN> backup database include current controlfile plus archivelog delete input;
$ scp -r fra 192.168.7.26:/u01/database/sybo3/ -->如果有必要将将备份文件打包，此处fra目录是闪回区
--Author : Robinson
--Blog : http://blog.csdn.net/robinson_0612
--ftp参数文件，如果没有pfile文件，可从target db生成。 create pfile from spfile;
$ scp $ORACLE_HOME/dbs/initsybo3.ora 192.168.7.26:$ORACLE_HOME/dbs
b、创建相应的dump文件夹
[oracle@linux4 database]$ more sybo3.sh
#!/bin/sh
mkdir -p /u01/database
mkdir -p /u01/database/sybo3/adump
mkdir -p /u01/database/sybo3/controlf
mkdir -p /u01/database/sybo3/fra
mkdir -p /u01/database/sybo3/oradata
mkdir -p /u01/database/sybo3/redo
mkdir -p /u01/database/sybo3/dpdump
mkdir -p /u01/database/sybo3/pfile
[oracle@linux4 database]$ ./sybo3.sh
c、配置辅助实例参数文件
--由于auxiliary DB与target DB不存在文件位置转换，因此无需作任何修改。下面是target DB 复制到auxiliary的参数文件内容
[oracle@linux4 ~]$ more /u01/oracle/db_1/dbs/initsybo3.ora
sybo3.__db_cache_size=113246208
sybo3.__java_pool_size=4194304
sybo3.__large_pool_size=4194304
sybo3.__oracle_base='/u01/oracle'#ORACLE_BASE set from environment
sybo3.__pga_aggregate_target=150994944
sybo3.__sga_target=226492416
sybo3.__shared_io_pool_size=0
sybo3.__shared_pool_size=96468992
sybo3.__streams_pool_size=0
*.audit_file_dest='/u01/database/sybo3/adump/'
*.audit_trail='db'
*.compatible='11.2.0.0.0'
*.control_files='/u01/database/sybo3/controlf/control01.ctl','/u01/database/sybo3/controlf/control02.ctl'
*.db_block_size=8192
*.db_domain='orasrv.com'
*.db_name='sybo3'
*.db_recovery_file_dest='/u01/database/sybo3/fra'
*.db_recovery_file_dest_size=4039114752
*.dg_broker_config_file1='/u01/database/sybo3/db_broker/dr1sybo3.dat'
*.dg_broker_config_file2='/u01/database/sybo3/db_broker/dr2sybo3.dat'
*.dg_broker_start=FALSE
*.diagnostic_dest='/u01/database/sybo3'
*.log_archive_dest_1=''
*.memory_target=374341632
*.open_cursors=300
*.processes=150
*.remote_login_passwordfile='EXCLUSIVE'
*.undo_tablespace='UNDOTBS1'
d、生成辅助实例密码文件
--直接使用orapwd命令完成
$ orapwd file=/u01/oracle/db_1/dbs/orapwsybo3 password=oracle entries=10
e、实施数据库克隆
--由于此次测试无需连接到target及catalog，因此可以跳过配置监听，可在克隆完毕后再配置
[oracle@linux4 ~]$ export ORACLE_SID=sybo3
[oracle@linux4 ~]$ sqlplus / as sysdba
SQL> startup nomount; -->启动辅助实例到nomount状态
[oracle@linux4 ~]$ rman auxiliary / -->直接使用auxiliary / 方式连接到辅助数据库
connected to auxiliary database: SYBO3 (not mounted)
RMAN> duplicate target database to sybo3 spfile
2> backup location '/u01/database/sybo3/fra/SYBO3'
3> nofilenamecheck;
Starting Duplicate Db at 31-JUL-13
contents of Memory Script:
{
restore clone spfile to '/u01/oracle/db_1/dbs/spfilesybo3.ora' from --->从自动备份还原spfile文件
'/u01/database/sybo3/fra/SYBO3/autobackup/2013_07_31/o1_mf_s_822220850_8zjy9lp8_.bkp';
sql clone "alter system set spfile= ''/u01/oracle/db_1/dbs/spfilesybo3.ora''";
}
executing Memory Script
Starting restore at 31-JUL-13
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=134 device type=DISK
channel ORA_AUX_DISK_1: restoring spfile from AUTOBACKUP /u01/database/sybo3/fra/SYBO3/autobackup/2013_07_31/o1_mf_s_822220850_8zjy9lp8_.bkp
channel ORA_AUX_DISK_1: SPFILE restore from AUTOBACKUP complete
Finished restore at 31-JUL-13
sql statement: alter system set spfile= ''/u01/oracle/db_1/dbs/spfilesybo3.ora''
contents of Memory Script:
{
sql clone "alter system set db_name = --->修改spfile并重启辅助实例
''SYBO3'' comment=
''duplicate'' scope=spfile";
shutdown clone immediate;
startup clone nomount;
}
executing Memory Script
sql statement: alter system set db_name = ''SYBO3'' comment= ''duplicate'' scope=spfile
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 376635392 bytes
Fixed Size 1336652 bytes
Variable Size 285215412 bytes
Database Buffers 83886080 bytes
Redo Buffers 6197248 bytes
contents of Memory Script:
{
sql clone "alter system set db_name =
''SYBO3'' comment=
''Modified by RMAN duplicate'' scope=spfile";
sql clone "alter system set db_unique_name =
''SYBO3'' comment=
''Modified by RMAN duplicate'' scope=spfile";
shutdown clone immediate;
startup clone force nomount -->下面的命令用于还原控制文件
restore clone primary controlfile from '/u01/database/sybo3/fra/SYBO3/autobackup/2013_07_31/o1_mf_s_822220850_8zjy9lp8_.bkp';
alter clone database mount;
}
executing Memory Script
sql statement: alter system set db_name = ''SYBO3'' comment= ''Modified by RMAN duplicate'' scope=spfile
sql statement: alter system set db_unique_name = ''SYBO3'' comment= ''Modified by RMAN duplicate'' scope=spfile
Oracle instance shut down
Oracle instance started
Total System Global Area 376635392 bytes
Fixed Size 1336652 bytes
Variable Size 285215412 bytes
Database Buffers 83886080 bytes
Redo Buffers 6197248 bytes
Starting restore at 31-JUL-13
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=133 device type=DISK
channel ORA_AUX_DISK_1: restoring control file
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
output file name=/u01/database/sybo3/controlf/control01.ctl
output file name=/u01/database/sybo3/controlf/control02.ctl
Finished restore at 31-JUL-13
database mounted
released channel: ORA_AUX_DISK_1
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=133 device type=DISK
RMAN-05538: WARNING: implicitly using DB_FILE_NAME_CONVERT
contents of Memory Script:
{
set until scn 1177881; --->设置时点恢复scn，修改datafile name.
set newname for datafile 1 to
"/u01/database/sybo3/oradata/system01.dbf";
set newname for datafile 2 to
"/u01/database/sybo3/oradata/sysaux01.dbf";
set newname for datafile 3 to
"/u01/database/sybo3/oradata/undotbs01.dbf";
set newname for datafile 4 to
"/u01/database/sybo3/oradata/users01.dbf";
set newname for datafile 5 to
"/u01/database/sybo3/oradata/example01.dbf";
restore --->该命令用于还原辅助数据库
clone database
;
}
executing Memory Script
executing command: SET until clause
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
Starting restore at 31-JUL-13
using channel ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00001 to /u01/database/sybo3/oradata/system01.dbf
channel ORA_AUX_DISK_1: restoring datafile 00002 to /u01/database/sybo3/oradata/sysaux01.dbf
channel ORA_AUX_DISK_1: restoring datafile 00003 to /u01/database/sybo3/oradata/undotbs01.dbf
channel ORA_AUX_DISK_1: restoring datafile 00004 to /u01/database/sybo3/oradata/users01.dbf
channel ORA_AUX_DISK_1: restoring datafile 00005 to /u01/database/sybo3/oradata/example01.dbf
channel ORA_AUX_DISK_1: reading from backup piece /u01/database/sybo3/fra/SYBO3/backupset/2013_07_31/o1_mf_nnndf_TAG20130731T103921_8zjy6s8p_.bkp
channel ORA_AUX_DISK_1: piece handle=/u01/database/sybo3/fra/SYBO3/backupset/2013_07_31/o1_mf_nnndf_TAG20130731T103921_8zjy6s8p_.bkp
tag=TAG20130731T103921
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:01:25
Finished restore at 31-JUL-13
contents of Memory Script:
{
switch clone datafile all; --->更新数据文件信息到控制文件
}
executing Memory Script
datafile 1 switched to datafile copy
input datafile copy RECID=1 STAMP=822223969 file name=/u01/database/sybo3/oradata/system01.dbf
datafile 2 switched to datafile copy
input datafile copy RECID=2 STAMP=822223969 file name=/u01/database/sybo3/oradata/sysaux01.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=3 STAMP=822223969 file name=/u01/database/sybo3/oradata/undotbs01.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=4 STAMP=822223969 file name=/u01/database/sybo3/oradata/users01.dbf
datafile 5 switched to datafile copy
input datafile copy RECID=5 STAMP=822223969 file name=/u01/database/sybo3/oradata/example01.dbf
contents of Memory Script:
{
set until scn 1177881;
recover --->recover 辅助数据库以及删除日志
clone database
delete archivelog
;
}
executing Memory Script
executing command: SET until clause
Starting recover at 31-JUL-13
using channel ORA_AUX_DISK_1
starting media recovery
channel ORA_AUX_DISK_1: starting archived log restore to default destination
channel ORA_AUX_DISK_1: restoring archived log
archived log thread=1 sequence=41
channel ORA_AUX_DISK_1: reading from backup piece /u01/database/sybo3/fra/SYBO3/backupset/2013_07_31/o1_mf_annnn_TAG20130731T104049_8zjy9k8g_.bkp
channel ORA_AUX_DISK_1: piece handle=/u01/database/sybo3/fra/SYBO3/backupset/2013_07_31/o1_mf_annnn_TAG20130731T104049_8zjy9k8g_.bkp
tag=TAG20130731T104049
channel ORA_AUX_DISK_1: restored backup piece 1
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
archived log file name=/u01/database/sybo3/fra/SYBO3/archivelog/2013_07_31/o1_mf_1_41_8zk1c4xq_.arc thread=1 sequence=41
channel clone_default: deleting archived log(s)
archived log file name=/u01/database/sybo3/fra/SYBO3/archivelog/2013_07_31/o1_mf_1_41_8zk1c4xq_.arc RECID=1 STAMP=822223972
media recovery complete, elapsed time: 00:00:01
Finished recover at 31-JUL-13
contents of Memory Script:
{
shutdown clone immediate; --->相关参数修改
startup clone nomount;
sql clone "alter system set db_name =
''SYBO3'' comment=
''Reset to original value by RMAN'' scope=spfile";
sql clone "alter system reset db_unique_name scope=spfile";
shutdown clone immediate;
startup clone nomount;
}
executing Memory Script
database dismounted
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 376635392 bytes
Fixed Size 1336652 bytes
Variable Size 285215412 bytes
Database Buffers 83886080 bytes
Redo Buffers 6197248 bytes
sql statement: alter system set db_name = ''SYBO3'' comment= ''Reset to original value by RMAN'' scope=spfile
sql statement: alter system reset db_unique_name scope=spfile
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area 376635392 bytes
Fixed Size 1336652 bytes
Variable Size 285215412 bytes
Database Buffers 83886080 bytes
Redo Buffers 6197248 bytes
sql statement: CREATE CONTROLFILE REUSE SET DATABASE "SYBO3" RESETLOGS ARCHIVELOG --->重建控制文件,隐式重置了dbid
MAXLOGFILES 16
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 8
MAXLOGHISTORY 292
LOGFILE
GROUP 1 SIZE 50 M ,
GROUP 2 SIZE 50 M ,
GROUP 3 SIZE 50 M
DATAFILE
'/u01/database/sybo3/oradata/system01.dbf'
CHARACTER SET AL32UTF8
contents of Memory Script:
{
set newname for tempfile 1 to
"/u01/database/sybo3/oradata/temp01.dbf";
switch clone tempfile all;
catalog clone datafilecopy "/u01/database/sybo3/oradata/sysaux01.dbf",
"/u01/database/sybo3/oradata/undotbs01.dbf",
"/u01/database/sybo3/oradata/users01.dbf",
"/u01/database/sybo3/oradata/example01.dbf";
switch clone datafile all;
}
executing Memory Script
executing command: SET NEWNAME
renamed tempfile 1 to /u01/database/sybo3/oradata/temp01.dbf in control file
cataloged datafile copy
datafile copy file name=/u01/database/sybo3/oradata/sysaux01.dbf RECID=1 STAMP=822223994
cataloged datafile copy
datafile copy file name=/u01/database/sybo3/oradata/undotbs01.dbf RECID=2 STAMP=822223994
cataloged datafile copy
datafile copy file name=/u01/database/sybo3/oradata/users01.dbf RECID=3 STAMP=822223994
cataloged datafile copy
datafile copy file name=/u01/database/sybo3/oradata/example01.dbf RECID=4 STAMP=822223994
datafile 2 switched to datafile copy
input datafile copy RECID=1 STAMP=822223994 file name=/u01/database/sybo3/oradata/sysaux01.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=2 STAMP=822223994 file name=/u01/database/sybo3/oradata/undotbs01.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=3 STAMP=822223994 file name=/u01/database/sybo3/oradata/users01.dbf
datafile 5 switched to datafile copy
input datafile copy RECID=4 STAMP=822223994 file name=/u01/database/sybo3/oradata/example01.dbf
contents of Memory Script:
{
Alter clone database open resetlogs;
}
executing Memory Script
database opened
Finished Duplicate Db at 31-JUL-13
--对于那些没有连接到target db或者catalog而使用duplicate方式克隆的数据库，必须要指定BACKUP LOCATION，否则收到如下错误提示。
--这是由于所有和备份相关的信息，包括备份位置都记录在catalog或controlfile里，但是duplicate方式发布命令时，此时controlfile还没有还原。
--RMAN-05546: DUPLICATE without TARGET and CATALOG connections requires that BACKUP LOCATION is specified
f、验证结果(根据需要创建监听)
[oracle@linux4 ~]$ sqlplus / as sysdba
SQL> select instance_name,host_name from v$instance;
INSTANCE_NAME HOST_NAME
---------------- ------------------------------
sybo3 linux4.orasrv.com
SQL> select * from t;
NAME ACTION
---------- --------------------
Robinson Transfer DB
Jackson Transfer DB by rman
4、后记
a、在异机克隆时，如果auxiliary DB使用了与target DB相同的磁盘配置，目录结构以及文件名时，必须指定NOFILENAMECHECK。
NOFILENAMECHECK可以阻止检查target DB的数据文件及联机日志文件是否处于正常使用的状态。而auxiliary DB与target DB的磁盘配置，
目录结构以及文件名任一不同时，应避免使用NOFILENAMECHECK。
b、对于没有连接到target DB或catalog的情形，应使用BACKUP LOCATION '<bak_dir>'指定备份文件所在的位置。
相关参考
RMAN 数据库克隆文件位置转换方法
基于 RMAN 的同机数据库克隆
基于用户管理的同机数据库克隆
Oracle 冷备份
Oracle 热备份
Oracle 备份恢复概念
Oracle 实例恢复
Oracle 基于用户管理恢复的处理
SYSTEM 表空间管理及备份恢复
SYSAUX表空间管理及恢复
Oracle 基于备份控制文件的恢复(unsing backup controlfile)
RMAN 概述及其体系结构
RMAN 配置、监控与管理
RMAN 备份详解
RMAN 还原与恢复
RMAN catalog 的创建和使用
基于catalog 创建RMAN存储脚本
基于catalog 的RMAN 备份与恢复
RMAN 备份路径困惑
自定义 RMAN 显示的日期时间格式
只读表空间的备份与恢复
Oracle 基于用户管理的不完全恢复
理解 using backup controlfile
使用RMAN实现异机备份恢复(WIN平台)
使用RMAN迁移文件系统数据库到ASM
基于Linux下 Oracle 备份策略(RMAN)
Linux 下RMAN备份shell脚本
使用RMAN迁移数据库到异机
RMAN 提示符下执行SQL语句
Oracle 基于 RMAN 的不完全恢复(incomplete recovery by RMAN)
rman 还原归档日志(restore archivelog)