Oracle 11gR2 使用RMAN Duplicate复制数据库
Oracle 11gR2 使用RMAN Duplicate复制数据库
作者:吴伟龙 PrudentWoo QQ:286507175
前言:
上周刚做完一个项目,用户要求RAC的数据库可以自己主动备份到另外一个单节点上,单节点可以正常拿起来就能用。当时跟他们讨论的是用ADG来做,但通过描写叙述后。用户认为假设要人工干预的话太麻烦。它不想做不论什么的人工干预,实现数据自己主动到这台单机上来。那仅仅是一台备用的数据库。没事的时候可以登录上去看看历史的数据情况。
这个时候我提出了11g的RMAN Duplicate方案,它可以在线实现异机的在线备份。且无需人工干预,通过网络将传输数据过来后可以自己主动open备机.
如图:
RMAN Duplicate 是从Oracle 10g就已经開始有的一个功能;可是在11g的时候进行了非常多增强,免去了10g版本号下须要人工拷贝到备机上过来进行恢复的尴尬境界。通过11g的Duplicate可以创建一个全然同样但DBID不同的备机数据库。在11g的RMAN Duplicate中可以通过Active database duplicate和Backup-based duplicate两种方法实现。我们在用户现场採用的是Active Database Duplicate;由于它不用先把目标数据库进行RMAN备份。仅仅须要目标数据库处于归档模式下就可以通过网络对数据库进行恢复。且恢复完毕后可以自己主动Open Duplicate Database。这样就正好满足了用户不用人工干预的需求。尤其是对于大数据库特别是TB级别的数据库其长处时非常明显,恢复前不须要进行单独的备份。降低了备份及拷贝备份文件的时间,同一时候还节省了备份空间。以下我们来进行完整的RAC to Single Instance的Active Database Duplicate操作。
一、环境介绍
HostName |
DBName |
public ip |
|
11gR2 RAC |
db01 |
woo1 |
192.168.7.51 |
db02 |
woo2 |
192.168.7.52 |
|
Duplicate |
standby |
woo |
192.168.7.55 |
二、開始配置Duplicate Database。过程例如以下:
2.1 构建辅助数据库文件夹结构,配置辅助数据库相关系统參数。
2.2 安装软件并创建数据库。
2.3 开启归档
2.3 创建pfile,并改动
2.4 创建辅助数据库实例口令文件
2.5 配置静态监听
2.6 用pfile文件,将辅助数据库启动到nomount状态
2.7 运行RMAN duplicate命令复制数据库
2.8 创建spfile文件
三、构建辅助数据库文件夹结构,配置辅助数据库相关參数。
(简)
/usr/sbin/groupadd -g 502 dba
/usr/sbin/groupadd -g 501 oinstall
/usr/sbin/useradd -u 502 -g oinstall -G dba oracle
mkdir -p /DBSoft/oraInventory
mkdir -p /DBSoft/oracle/product/11.2.4/dbhome_1
chown -R oracle:oinstall /DBSoft
chmod -R 775 /DBSoft
echo "oracle"|passwd --stdin oracle
yum install -y setarch binutils compat-libstdc++-33 compat-libcap1 compat-db compat-libstdc++ compat-gcc elfutils-libelf elfutils-libelf-devel gcc gcc-c++ glibc glibc-common glibc
-devel libaio libaio-devel libgcc libstdc++ libstdc++-devel make ksh numactl sysstat libXp unixODBC unixODBC-devel udev
cat >> /etc/sysctl.conf <<EOF
kernel.shmall = 4294967296
kernel.sem = 510 65280 510 128
kernel.shmmni = 4096
kernel.shmmax = 137438953472
net.ipv4.ip_local_port_range = 9000 65500
net.core.rmem_default = 1048576
net.core.rmem_max = 4194304
net.core.wmem_default = 262144
net.core.wmem_max = 1048576
fs.file-max = 6815744
fs.aio-max-nr = 1048576
vm.swappiness = 0
vm.dirty_background_ratio = 3
vm.dirty_ratio = 80
vm.dirty_expire_centisecs = 500
vm.dirty_writeback_centisecs = 100
net.ipv4.tcp_sack = 0
net.ipv4.tcp_timestamps = 0
net.ipv4.conf.default.rp_filter = 0
net.ipv4.tcp_wmem = 262144
net.ipv4.tcp_rmem = 4194304
EOF /sbin/sysctl –p
cat >> /etc/security/limits.conf <<EOF
oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 65536
oracle hard nofile 65536
oracle soft memlock 3145728
oracle hard memlock 3145728 #signaturelevin
EOF
cat >> /etc/profile <<EOF if [ \$USER = "oracle" ]; then
if [ \$SHELL = "/bin/ksh" ]; then
ulimit -p 16384
ulimit -n 65536
else
ulimit -u 16384 -n 65536
fi
fi
EOF cat >> /home/oracle/.bash_profile <<EOF
export TMP=/tmp
export TMPDIR=\$TMP
export EDIT=vi
alias vi=vim
export ORACLE_HOSTNAME=$hostname
export ORACLE_UNQNAME=$db_name
export ORACLE_BASE=/DBSoft/oracle
export ORACLE_HOME=\$ORACLE_BASE/product/11.2.4/dbhome_1
export ORACLE_SID=$instance_name
export ORACLE_TERM=xterm
export PATH=/usr/sbin:\$PATH
export PATH=\$ORACLE_HOME/bin:\$PATH
export LD_LIBRARY_PATH=\$ORACLE_HOME/lib:/lib:/usr/lib
export CLASSPATH=\$ORACLE_HOME/JRE:\$ORACLE_HOME/jlib:\$ORACLE_HOME/rdbms/jlib
export NLS_LANG=AMERICAN_AMERICA AL32UTF16
umask 022
EOF
四、安装软件并创建数据库
./runInstaller -silent -debug -force -responseFile /home/oracle/database/response/db_install.rsp dbca -silent -responsefile /home/oracle/database/response/dbca.rsp
五、开启归档
SQL> alter system set log_archive_dest_1=\'location=+FRA001/archive\' scope=spfile sid=\'woo1\'; System altered.
SQL> alter database archivelog; Database altered.
SQL> alter database open; Database altered. SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination +FRA001/archive
Oldest online log sequence 978
Next log sequence to archive 979
Current log sequence 979
SQL> alter system switch logfile;
alter system switch logfile; System altered. SQL> System altered.
SQL> archive log list;
Database log mode Archive Mode
Automatic archival Enabled
Archive destination +FRA001/archive
Oldest online log sequence 980
Next log sequence to archive 981
Current log sequence 981
六、配置静态监听
RAC节点监听信息例如以下:
$ cd $ORACLE_HOME/network/admin
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = scan.woo.com)(PORT = 1521))
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
)
) SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = woo.com)
(ORACLE_HOME = /DBSoft/oracle/product/11.2.0/db_1)
(SID_NAME = woo)
)
)
ADR_BASE_LISTENER = /DBSoft/oracle
单节点监听信息例如以下:
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.7.55)(PORT = 1521))
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
)
) SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = woo.com)
(ORACLE_HOME = /DBSoft/oracle/product/11.2.0/db_1)
(SID_NAME = woo)
)
)
ADR_BASE_LISTENER = /DBSoft/oracle
配置全部节点tnsname信息例如以下:
WOO =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = scan.woo.com)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = woo)
)
) DUPLICATE =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.7.55)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = woo)
)
)
六、启动数据库到nomount状态
SQL> startup nomount
ORA-32004: obsolete or deprecated parameter(s) specified for RDBMS instance
ORACLE instance started. Total System Global Area 954155008 bytes
Fixed Size 1368632 bytes
Variable Size 306187720 bytes
Database Buffers 641728512 bytes
Redo Buffers 4870144 bytes
SQL>exit ---------必须退出
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options
七、 在RAC端随意节点通过RMAN连接到目标实例和辅助实例。运行duplicate命令复制数据库:
[oracle@db01 ~]$ rman target sys/oracle@woo auxiliary sys/oracle@standby Recovery Manager: Release 11.2.0.4.0 - Production on Wed Jun 3 19:39:00 2015 Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved. connected to target database: WOO (DBID=4218366793)
connected to auxiliary database: WOO (not mounted) RMAN>
RMAN> duplicate target database to woo from active database nofilenamecheck; Starting Duplicate Db at 03-JUN-15
using target database control file instead of recovery catalog
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=19 device type=DISK contents of Memory Script:
{
sql clone "alter system set db_name =
''WOO'' comment=
''Modified by RMAN duplicate'' scope=spfile";
sql clone "alter system set db_unique_name =
''WOO'' comment=
''Modified by RMAN duplicate'' scope=spfile";
shutdown clone immediate;
startup clone force nomount
backup as copy current controlfile auxiliary format '/DBSoft/oracle/oradata/woo/control01.ctl';
restore clone controlfile to '/DBSoft/oracle/fast_recovery_area/woo/control02.ctl' from
'/DBSoft/oracle/oradata/woo/control01.ctl';
alter clone database mount;
}
executing Memory Script
sql statement: alter system set db_name = ''WOO'' comment= ''Modified by RMAN duplicate'' scope=spfile sql statement: alter system set db_unique_name = ''WOO'' comment= ''Modified by RMAN duplicate'' scope=spfile Oracle instance shut down Oracle instance started Total System Global Area 954155008 bytes Fixed Size 1368632 bytes
Variable Size 306187720 bytes
Database Buffers 641728512 bytes
Redo Buffers 4870144 bytes Starting backup at 03-JUN-15
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=43 device type=DISK
channel ORA_DISK_1: starting datafile copy
copying current control file
output file name=/DBSoft/oracle/product/11.2.4/dbhome_1/dbs/snapcf_woo.f tag=TAG20150603T194000 RECID=3 STAMP=881437202
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:08
Finished backup at 03-JUN-15 Starting restore at 03-JUN-15
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=19 device type=DISK channel ORA_AUX_DISK_1: copied control file copy
Finished restore at 03-JUN-15 database mounted contents of Memory Script:
{
sql clone 'alter database flashback off';
set newname for datafile 1 to
"/DBSoft/oracle/oradata/woo/system01.dbf";
set newname for datafile 2 to
"/DBSoft/oracle/oradata/woo/sysaux01.dbf";
set newname for datafile 3 to
"/DBSoft/oracle/oradata/woo/undotbs01.dbf";
set newname for datafile 4 to
"/DBSoft/oracle/oradata/woo/users01.dbf";
backup as copy reuse
datafile 1 auxiliary format
"/DBSoft/oracle/oradata/woo/system01.dbf" datafile
2 auxiliary format
"/DBSoft/oracle/oradata/woo/sysaux01.dbf" datafile
3 auxiliary format
"/DBSoft/oracle/oradata/woo/undotbs01.dbf" datafile
4 auxiliary format
"/DBSoft/oracle/oradata/woo/users01.dbf" ;
sql 'alter system archive log current';
}
executing Memory Script sql statement: alter database flashback off executing command: SET NEWNAME executing command: SET NEWNAME executing command: SET NEWNAME executing command: SET NEWNAME
Starting backup at 03-JUN-15
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00001 name=/DBSoft/oracle/oradata/woo/system01.dbf
output file name=/DBSoft/oracle/oradata/woo/system01.dbf tag=TAG20150603T194019
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:04:47
channel ORA_DISK_1: starting datafile copy
input datafile file number=00002 name=/DBSoft/oracle/oradata/woo/sysaux01.dbf
output file name=/DBSoft/oracle/oradata/woo/sysaux01.dbf tag=TAG20150603T194019
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:03:07
channel ORA_DISK_1: starting datafile copy
input datafile file number=00003 name=/DBSoft/oracle/oradata/woo/undotbs01.dbf
output file name=/DBSoft/oracle/oradata/woo/undotbs01.dbf tag=TAG20150603T194019
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:15
channel ORA_DISK_1: starting datafile copy
input datafile file number=00004 name=/DBSoft/oracle/oradata/woo/users01.dbf
output file name=/DBSoft/oracle/oradata/woo/users01.dbf tag=TAG20150603T194019
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 03-JUN-15 sql statement: alter system archive log current contents of Memory Script:
{
backup as copy reuse
archivelog like "/DBArchive/archive/1_63_878860684.dbf" auxiliary format
"/DBArchive2/archive/1_63_878860684.dbf" ;
catalog clone archivelog "/DBArchive2/archive/1_63_878860684.dbf";
switch clone datafile all;
}
executing Memory Script Starting backup at 03-JUN-15
using channel ORA_DISK_1
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=63 RECID=38 STAMP=881437711
output file name=/DBArchive2/archive/1_63_878860684.dbf RECID=0 STAMP=0
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
Finished backup at 03-JUN-15 cataloged archived log
archived log file name=/DBArchive2/archive/1_63_878860684.dbf RECID=38 STAMP=881437696 datafile 1 switched to datafile copy
input datafile copy RECID=3 STAMP=881437696 file name=/DBSoft/oracle/oradata/woo/system01.dbf
datafile 2 switched to datafile copy
input datafile copy RECID=4 STAMP=881437696 file name=/DBSoft/oracle/oradata/woo/sysaux01.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=5 STAMP=881437696 file name=/DBSoft/oracle/oradata/woo/undotbs01.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=6 STAMP=881437696 file name=/DBSoft/oracle/oradata/woo/users01.dbf contents of Memory Script:
{
set until scn 1338740;
recover
clone database
delete archivelog
;
}
executing Memory Script executing command: SET until clause Starting recover at 03-JUN-15
using channel ORA_AUX_DISK_1 starting media recovery archived log for thread 1 with sequence 63 is already on disk as file /DBArchive2/archive/1_63_878860684.dbf
archived log file name=/DBArchive2/archive/1_63_878860684.dbf thread=1 sequence=63
media recovery complete, elapsed time: 00:00:00
Finished recover at 03-JUN-15
Oracle instance started Total System Global Area 954155008 bytes Fixed Size 1368632 bytes
Variable Size 306187720 bytes
Database Buffers 641728512 bytes
Redo Buffers 4870144 bytes contents of Memory Script:
{
sql clone "alter system set db_name =
''WOO'' 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 sql statement: alter system set db_name = ''WOO'' 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 954155008 bytes Fixed Size 1368632 bytes
Variable Size 306187720 bytes
Database Buffers 641728512 bytes
Redo Buffers 4870144 bytes
sql statement: CREATE CONTROLFILE REUSE SET DATABASE "WOO" RESETLOGS ARCHIVELOG
MAXLOGFILES 16
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 8
MAXLOGHISTORY 292
LOGFILE
GROUP 1 ( '/DBSoft/oracle/oradata/woo/redo01.log' ) SIZE 50 M REUSE,
GROUP 2 ( '/DBSoft/oracle/oradata/woo/redo02.log' ) SIZE 50 M REUSE,
GROUP 3 ( '/DBSoft/oracle/oradata/woo/redo03.log' ) SIZE 50 M REUSE
DATAFILE
'/DBSoft/oracle/oradata/woo/system01.dbf'
CHARACTER SET WE8MSWIN1252 contents of Memory Script:
{
set newname for tempfile 1 to
"/DBSoft/oracle/oradata/woo/temp01.dbf";
switch clone tempfile all;
catalog clone datafilecopy "/DBSoft/oracle/oradata/woo/sysaux01.dbf",
"/DBSoft/oracle/oradata/woo/undotbs01.dbf",
"/DBSoft/oracle/oradata/woo/users01.dbf";
switch clone datafile all;
}
executing Memory Script executing command: SET NEWNAME renamed tempfile 1 to /DBSoft/oracle/oradata/woo/temp01.dbf in control file cataloged datafile copy
datafile copy file name=/DBSoft/oracle/oradata/woo/sysaux01.dbf RECID=1 STAMP=881437718
cataloged datafile copy
datafile copy file name=/DBSoft/oracle/oradata/woo/undotbs01.dbf RECID=2 STAMP=881437718
cataloged datafile copy
datafile copy file name=/DBSoft/oracle/oradata/woo/users01.dbf RECID=3 STAMP=881437718 datafile 2 switched to datafile copy
input datafile copy RECID=1 STAMP=881437718 file name=/DBSoft/oracle/oradata/woo/sysaux01.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=2 STAMP=881437718 file name=/DBSoft/oracle/oradata/woo/undotbs01.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=3 STAMP=881437718 file name=/DBSoft/oracle/oradata/woo/users01.dbf contents of Memory Script:
{
Alter clone database open resetlogs;
}
executing Memory Script database opened
Reenabling controlfile options for auxiliary database
Executing: alter database flashback on
Finished Duplicate Db at 03-JUN-15 RMAN>
至此,duplicate已经完毕,standby数据库已经起来了。
[oracle@db02 ~]$ sqlplus / as sysdba SQL*Plus: Release 11.2.0.4.0 Production on Wed Jun 3 19:53:02 2015 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining,
Oracle Database Vault and Real Application Testing options SQL> col host_name format a15
SQL> col file_name format a40
SQL> set line 150
SQL> select host_name,instance_name,status from gv$instance; HOST_NAME INSTANCE_NAME STATUS
--------------- ---------------- ------------
db02 woo OPEN SQL> select tablespace_name,file_name from dba_data_files; TABLESPACE_NAME FILE_NAME
------------------------------ ----------------------------------------
SYSTEM /DBSoft/oracle/oradata/woo/system01.dbf
SYSAUX /DBSoft/oracle/oradata/woo/sysaux01.dbf
UNDOTBS1 /DBSoft/oracle/oradata/woo/undotbs01.dbf
USERS /DBSoft/oracle/oradata/woo/users01.dbf
注意:这里的nofilenamecheck參数须要解释下:
假设在复制时,位置不同一时候,我们会用參数db_file_name_convert 对文件位置进行转换。 可是在这个复制演示样例中我们用的是同样的位置。 所以这里必须加上nofilenamecheck參数。 该參数通知复制操作不必在运行还原操作前确认文件名称是不同的。假设没有指定nofilenamecheck參数,rman会给出例如以下错误:
RMAN-05001: auxiliary filename /DBSoft/oracle/oradata/woo/users01.dbf conflicts with a file used by the target database
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