使用dataguard将单实例数据库转换为rac数据库
我们常常将oracle rac数据库通过dataguard容灾到一个单实例数据库中。当生产库出现问题后能够将生产库切换到dgserver上。而当生产库rac修复完毕后。我们相同能够通过dg将数据回切到生产库中。
此次測试将单实例数据库通过dg转换为rac数据库，这个单实例是刚创建的，并非由rac通过dg生成的。
在做dg之前须要安装完毕grid，不须要创建数据库实例。在日志应用的时候必须仅仅能是一个实例应用。
详细环境例如以下：
单实例库：
数据库版本号:11.2.0.4.0
sid：suq
db_unique_name=suq
ip：192.168.56.35
hostname:11g1
rac数据库：
数据库版本号:11.2.0.4.0
sid：suq1、suq2
db_unique_name=suq1
ip地址规划：
#PUBLIC
192.168.56.110 suq1
192.168.56.112 suq2
#VIP
192.168.56.111 suq1-vip
192.168.56.113 suq2-vip
#PRIV
172.168.1.21 suq1-priv
172.168.1.23 suq2-priv
#SCAN
192.168.56.25 suq-cluster-scan
详细过程例如以下：
1.配置一些rac和dg的基本參数，包含：
改动主库force logging、创建standby logfile、创建password文件而且复制到rac下、加入主库和备库的服务命名：
alter database force logging;
alter database add standby logfile group 4 ('/opt/oracle/oradata/suq/stand_redo04.log') size 50m;
alter database add standby logfile group 5 ('/opt/oracle/oradata/suq/stand_redo05.log') size 50m;
alter database add standby logfile group 6 ('/opt/oracle/oradata/suq/stand_redo06.log') size 50m;
alter database add standby logfile group 7 ('/opt/oracle/oradata/suq/stand_redo07.log') size 50m;
##
primary=
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.56.35)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = suq)
)
)
standby=
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.56.111)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = suq1)
(UR = A)
)
)
注意：standby端即rac端的ip地址写的是suq1的vip地址，并且须要加上(UR=A)选项，否则通过sqlplus连接不到rac实例。
2.生成standby端的oracle 參数文件。这一步參数里面的内容及其重要。必须写正确。特别是rac和dg的參数。眼下我的rac有三个磁盘组
[grid@suq2 ~]$ asmcmd lsdg
State Type Rebal Sector Block AU Total_MB Free_MB Req_mir_free_MB Usable_file_MB Offline_disks Voting_files Name
MOUNTED EXTERN N 512 4096 1048576 3435 3329 0 3329 0 N BACKUP/
MOUNTED EXTERN N 512 4096 1048576 4305 1988 0 1988 0 N DATADG/
MOUNTED EXTERN N 512 4096 1048576 1458 1058 0 1058 0 Y SYSTEMDG/
以下是我写好的一个參数文件：
suq.__db_cache_size=335544320
suq.__java_pool_size=4194304
suq.__large_pool_size=4194304
suq.__oracle_base='/u01/app'
suq.__pga_aggregate_target=335544320
suq.__sga_target=503316480
suq.__shared_io_pool_size=0
suq.__shared_pool_size=146800640
suq.__streams_pool_size=0
*.audit_file_dest='/u01/app/oracle/admin/suq'
*.audit_trail='none'
*.compatible='11.2.0.4.0'
*.control_files='+DATADG/suq/control.ctl'
*.db_block_size=8192
*.db_domain=''
*.db_name='suq'
*.db_recovery_file_dest='+BACKUP'
*.db_recovery_file_dest_size=5218762752
*.diagnostic_dest='/u01/app/oracle'
*.memory_target=838860800
*.open_cursors=300
*.processes=150
*.remote_login_passwordfile='EXCLUSIVE'
*.undo_tablespace='UNDOTBS1'
#### rac parameter
suq1.local_listener='(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.111)(PORT=1521))'
suq2.local_listener='(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.113)(PORT=1521))'
suq1.undo_tablespace='UNDOTBS1'
suq2.undo_tablespace='UNDOTBS2'
suq1.remote_listener='suq-cluster-scan:1521'
suq2.remote_listener='suq-cluster-scan:1521'
suq1.instance_name=suq1
suq2.instance_name=suq2
suq1.instance_number=1
suq2.instance_number=2
*.cluster_database=true
*.cluster_database_instances=2
*.db_create_file_dest='+DATADG'
*.db_create_online_log_dest_1='+DATADG'
suq1.thread=1
suq2.thread=2
### dg parameter
*.db_unique_name=suq1
*.log_archive_config='dg_config=(suq,suq1)'
*.standby_file_management='AUTO'
*.db_file_name_convert='/opt/oracle/oradata/suq','+DATADG/suq/datafile'
*.log_file_name_convert='/opt/oracle/oradata/suq','+DATADG/suq/datafile'
*.log_archive_dest_1='location=+datadg/suq/archivelog valid_for=(all_logfiles,all_roles) db_unique_name=suq1'
*.log_archive_dest_2='service=primary lgwr async valid_for=(online_logfiles,primary_role) db_unique_name=suq'
*.fal_server=primary
*.fal_client=standby
注意：suq1、suq2的local_listener和remote_listener必须配置正确。否则打开库之后scan ip可能失效
3.配置主库的dg參数：
alter system set log_archive_config='dg_config=(suq,suq1)' scope=both; alter system set log_archive_dest_1='location=/opt/arch valid_for=(all_logfiles,all_roles) db_unique_name=suq' scope=both; alter system set log_archive_dest_2='service=standby lgwr async valid_for=(online_logfiles,primary_role) db_unique_name=suq1' scope=both; alter system set fal_server=suq1 scope=both; alter system set fal_client=suq scope=both;
4.在保证全部须要的文件夹都已经创建完毕的情况下，将备库启动到nomount。而且測试tnsnames的连通性：
SQL>startup nomount pfile='/home/oracle/initsuq1.ora'
ORACLE instance started. Total System Global Area 835104768 bytes
Fixed Size 2257840 bytes
Variable Size 553651280 bytes
Database Buffers 272629760 bytes
Redo Buffers 6565888 bytes
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options
[oracle@suq1 ~]$ lsnrctl status LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 26-JUL-2015 21:27:45 Copyright (c) 1991, 2013, Oracle. All rights reserved. Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 11.2.0.4.0 - Production
Start Date 26-JUL-2015 18:58:27
Uptime 0 days 2 hr. 29 min. 17 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /u01/11.2.0/grid/network/admin/listener.ora
Listener Log File /u01/app/oracle/diag/tnslsnr/suq1/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=LISTENER)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.56.110)(PORT=1521)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.56.111)(PORT=1521)))
Services Summary...
Service "+ASM" has 1 instance(s).
Instance "+ASM1", status READY, has 1 handler(s) for this service...
Service "suq1" has 1 instance(s).
Instance "suq1", status BLOCKED, has 1 handler(s) for this service...
The command completed successfully [oracle@11g1 ~]$ sqlplus sys/manager@standby as sysdba SQL*Plus: Release 11.2.0.4.0 Production on Sun Jul 26 21:48:08 2015 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Data Mining and Real Application Testing options SQL> exit [oracle@suq1 ~]$ sqlplus sys/manager@primary as sysdba SQL*Plus: Release 11.2.0.4.0 Production on Sun Jul 26 21:50:25 2015 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options SQL> exit
5.使用duplicate 创建standby database：
[oracle@11g1 arch]$ rman target / Recovery Manager: Release 11.2.0.4.0 - Production on Sun Jul 26 22:28:11 2015 Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved. connected to target database: SUQ (DBID=1469685490) RMAN> connect auxiliary sys/manager@standby connected to auxiliary database: SUQ (not mounted) RMAN> duplicate target database for standby from active database; Starting Duplicate Db at 26-JUL-15
using target database control file instead of recovery catalog
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=141 instance=suq1 device type=DISK contents of Memory Script:
{
backup as copy reuse
targetfile '/opt/oracle/product/OraHome11204/dbs/orapwsuq' auxiliary format
'/u01/app/oracle/product/11.2.0/db_1/dbs/orapwsuq1' ;
}
executing Memory Script Starting backup at 26-JUL-15
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=147 device type=DISK
Finished backup at 26-JUL-15 contents of Memory Script:
{
backup as copy current controlfile for standby auxiliary format '+DATADG/suq/control.ctl';
}
executing Memory Script Starting backup at 26-JUL-15
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
copying standby control file
output file name=/opt/oracle/product/OraHome11204/dbs/snapcf_suq.f tag=TAG20150726T222820 RECID=3 STAMP=886112900
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 26-JUL-15 contents of Memory Script:
{
sql clone 'alter database mount standby database';
}
executing Memory Script sql statement: alter database mount standby database contents of Memory Script:
{
set newname for tempfile 1 to
"+DATADG/suq/datafile/temp01.dbf";
switch clone tempfile all;
set newname for datafile 1 to
"+DATADG/suq/datafile/system01.dbf";
set newname for datafile 2 to
"+DATADG/suq/datafile/sysaux01.dbf";
set newname for datafile 3 to
"+DATADG/suq/datafile/undotbs01.dbf";
set newname for datafile 4 to
"+DATADG/suq/datafile/users01.dbf";
backup as copy reuse
datafile 1 auxiliary format
"+DATADG/suq/datafile/system01.dbf" datafile
2 auxiliary format
"+DATADG/suq/datafile/sysaux01.dbf" datafile
3 auxiliary format
"+DATADG/suq/datafile/undotbs01.dbf" datafile
4 auxiliary format
"+DATADG/suq/datafile/users01.dbf" ;
sql 'alter system archive log current';
}
executing Memory Script executing command: SET NEWNAME renamed tempfile 1 to +DATADG/suq/datafile/temp01.dbf in control file executing command: SET NEWNAME executing command: SET NEWNAME executing command: SET NEWNAME executing command: SET NEWNAME Starting backup at 26-JUL-15
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00001 name=/opt/oracle/oradata/suq/system01.dbf
output file name=+DATADG/suq/datafile/system01.dbf tag=TAG20150726T222829
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:45
channel ORA_DISK_1: starting datafile copy
input datafile file number=00002 name=/opt/oracle/oradata/suq/sysaux01.dbf
output file name=+DATADG/suq/datafile/sysaux01.dbf tag=TAG20150726T222829
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:45
channel ORA_DISK_1: starting datafile copy
input datafile file number=00003 name=/opt/oracle/oradata/suq/undotbs01.dbf
output file name=+DATADG/suq/datafile/undotbs01.dbf tag=TAG20150726T222829
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=/opt/oracle/oradata/suq/users01.dbf
output file name=+DATADG/suq/datafile/users01.dbf tag=TAG20150726T222829
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01
Finished backup at 26-JUL-15 sql statement: alter system archive log current contents of Memory Script:
{
switch clone datafile all;
}
executing Memory Script datafile 1 switched to datafile copy
input datafile copy RECID=3 STAMP=886113015 file name=+DATADG/suq/datafile/system01.dbf
datafile 2 switched to datafile copy
input datafile copy RECID=4 STAMP=886113015 file name=+DATADG/suq/datafile/sysaux01.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=5 STAMP=886113015 file name=+DATADG/suq/datafile/undotbs01.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=6 STAMP=886113015 file name=+DATADG/suq/datafile/users01.dbf
Finished Duplicate Db at 26-JUL-15 RMAN> exit Recovery Manager complete.
6.standby开启实时应用：
SQL> alter database recover managed standby database disconnect from session; SQL> alter database recover managed standby database cancel; SQL> alter database open read only; Database altered. SQL> alter database recover managed standby database using current logfile disconnect from session; Database altered.
注意：我在做到这一步的时候一開始发现主库怎么也不向备库发送归档文件，也没有不论什么报错信息。搞了非常长时间。后来将log_archive_dest_state_2又一次设置为enable后就正常了。
7.switch over。将备库转换为主库，分别在主库我备库进行角色转换：
主库： SQL> SELECT SWITCHOVER_STATUS FROM V$DATABASE; SWITCHOVER_STATUS
--------------------
SESSIONS ACTIVE 注：当SWITCHOVER_STATUS的值为TO STANDBY or SESSIONS ACTIVE的时候表示主库能够支持SWITCHOVER. SQL> ALTER DATABASE COMMIT TO SWITCHOVER TO PHYSICAL STANDBY WITH SESSION SHUTDOWN; Database altered. 备库： SQL> SELECT SWITCHOVER_STATUS FROM V$DATABASE; SWITCHOVER_STATUS
--------------------
SESSIONS ACTIVE 注：仅仅有SWITCHOVER_STATUS的值为TO PRIMARY or SESSIONS ACTIVE的状态时。表示备库当前支持switch over操作。 SQL> ALTER DATABASE COMMIT TO SWITCHOVER TO PRIMARY with session shutdown; Database altered. SQL> select status from v$instance; STATUS
------------
MOUNTED SQL> alter database open; Database altered.
8.到这一步，rac的一个节点已经能够正常打开数据库了，可是节点2须要的redo，undo表空间都还没有。须要手工创建：
SQL> alter database add logfile thread 2 group 8 ('+DATADG/suq/datafile/redo08.log') size 50m;
Database altered.
SQL> alter database add logfile thread 2 group 9 ('+DATADG/suq/datafile/redo09.log') size 50m;
Database altered.
SQL> alter database add logfile thread 2 group 10 ('+DATADG/suq/datafile/redo10.log') size 50m;
Database altered.
SQL> create undo tablespace undotbs2 datafile '+DATADG/suq/datafile/undotbs02.dbf' size 20m;
Tablespace created.
SQL> alter database enable public thread 2;
Database altered.
SQL> @?
/rdbms/admin/catclust.sql
Package created.
Package body created.
PL/SQL procedure successfully completed.
View created.
Synonym created.
Grant succeeded.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
View created.
Grant succeeded.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
Synonym created.
View created.
Grant succeeded.
Synonym created.
View created.
Grant succeeded.
Synonym created.
PL/SQL procedure successfully completed.
节点2打开数据库。測试数据库是否正常：
[oracle@suq2 ~]$ sqlplus / as sysdba SQL*Plus: Release 11.2.0.4.0 Production on Mon Jul 27 09:54:00 2015 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to an idle instance. SQL> startup
ORACLE instance started. Total System Global Area 835104768 bytes
Fixed Size 2257840 bytes
Variable Size 553651280 bytes
Database Buffers 272629760 bytes
Redo Buffers 6565888 bytes
Database mounted.
Database opened.
SQL> SQL> select * from v$active_instances。 INST_NUMBER INST_NAME
----------- --------------------------------------------------
1 suq1:suq1 2 suq2:suq2 SQL> select * from v$Log; GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIM NEXT_CHANGE# NEXT_TIME
---------- ---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- --------- ------------ ---------
1 1 35 52428800 512 1 NO CURRENT 288331 27-JUL-15 2.8147E+14
2 1 33 52428800 512 1 YES INACTIVE 281944 27-JUL-15 282047 27-JUL-15
3 1 34 52428800 512 1 YES ACTIVE 282047 27-JUL-15 288331 27-JUL-15
8 2 4 52428800 512 1 NO CURRENT 288227 27-JUL-15 2.8147E+14
9 2 2 52428800 512 1 YES INACTIVE 286810 27-JUL-15 286815 27-JUL-15
10 2 3 52428800 512 1 YES ACTIVE 286815 27-JUL-15 288227 27-JUL-15
8.此时的数据库是能够正常打开使用了，一般还需将參数文件写到asm中，并且此时的数据库都是本地管理，并没有注冊到grid中，还须要手工注冊：
[grid@suq1 admin]$ srvctl config database
[grid@suq1 admin]$
[grid@suq1 admin]$ crsctl stat res -t
--------------------------------------------------------------------------------
NAME TARGET STATE SERVER STATE_DETAILS
--------------------------------------------------------------------------------
Local Resources
--------------------------------------------------------------------------------
ora.BACKUP.dg
ONLINE ONLINE suq1
ONLINE ONLINE suq2
ora.DATADG.dg
ONLINE ONLINE suq1
ONLINE ONLINE suq2
ora.LISTENER.lsnr
ONLINE ONLINE suq1
ONLINE ONLINE suq2
ora.SYSTEMDG.dg
ONLINE ONLINE suq1
ONLINE ONLINE suq2
ora.asm
ONLINE ONLINE suq1 Started
ONLINE ONLINE suq2 Started
ora.gsd
OFFLINE OFFLINE suq1
OFFLINE OFFLINE suq2
ora.net1.network
ONLINE ONLINE suq1
ONLINE ONLINE suq2
ora.ons
ONLINE ONLINE suq1
ONLINE ONLINE suq2
ora.registry.acfs
ONLINE ONLINE suq1
ONLINE ONLINE suq2
--------------------------------------------------------------------------------
Cluster Resources
--------------------------------------------------------------------------------
ora.LISTENER_SCAN1.lsnr
1 ONLINE ONLINE suq2
ora.cvu
1 ONLINE ONLINE suq2
ora.oc4j
1 ONLINE ONLINE suq2
ora.scan1.vip
1 ONLINE ONLINE suq2
ora.suq1.vip
1 ONLINE ONLINE suq1
ora.suq2.vip
1 ONLINE ONLINE suq2 [oracle@suq1 ~]$ srvctl add database -d suq -o /u01/app/oracle/product/11.2.0/db_1
[oracle@suq1 ~]$ srvctl config database
suq
[oracle@suq1 ~]$ srvctl add instance -d suq -n suq1 -i suq1
[oracle@suq1 ~]$ srvctl add instance -d suq -n suq2 -i suq2 SQL> create spfile='+datadg' from pfile; File created.
[root@suq1 cssd]# srvctl modify database -d suq -p '+datadg/suq1/parameterfile/spfile.325.886161615'
[oracle@suq1 dbs]$ srvctl config database -d suq -a
Database unique name: suq
Database name:
Oracle home: /u01/app/oracle/product/11.2.0/db_1
Oracle user: oracle
Spfile: +datadg/suq1/parameterfile/spfile.325.886161615
Domain:
Start options: open
Stop options: immediate
Database role: PRIMARY
Management policy: AUTOMATIC
Server pools: suq
Database instances: suq1,suq2
Disk Groups:
Mount point paths:
Services:
Type: RAC
Database is enabled
Database is administrator managed
查看一下监听，有可能还须要改动services_name參数：
SQL> alter system set service_names=suq scope=both;
到此，单实例已经转换完毕了rac数据库。能够重新启动一下机器，看看数据库是否能自己主动启动，资源是否正常。
good luck。
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