在前面Oracle 10g DataGuard学习（二）中解释了DG的redo传输及应用的原理，为了进一步理解DG，同时便于后续从实战层面演示DG配置、创建、切换等过程，该篇会解释DG三种数据保护模式及如何设置这三种保护模式。

DG共有三种运行模式：最大保护模式、最大可用性模式、最大性能模式。在DG实际生产中环境中，可以根据不同的需求选择不同的运行模式，以下为官档对三种数据保护模式的说明：
1.1 Maximum Protection Mode
This protection mode ensures that no data loss will occur if the primary database fails. To provide this level of protection, the redo data needed to recover each transaction must be written to both the local online redo log and to the standby redo log on at least one standby database before the transaction commits. To ensure data loss cannot occur, the primary database shuts down if a fault prevents it from writing its redo stream to at least one remote standby redo log. For multiple-instance RAC databases, Data Guard shuts down the primary database if it is unable to write the redo records to at least one properly configured database instance. The maximum protection mode requires that at least one standby instance has a standby redo log and the LGWR, SYNC, and AFFIRM attributes be used on the LOG_ARCHIVE_DEST_n parameter for this destination.
1.2 Maximum Availability Mode
This protection mode provides the highest level of data protection that is possible without compromising the availability of the primary database. Like maximum protection mode, a transaction will not commit until the redo needed to recover that transaction is written to the local online redo log and to at least one remote standby redo log. Unlike maximum protection mode, the primary database does not shut down if a fault prevents it from writing its redo stream to a remote standby redo log. Instead, the primary database operates in maximum performance mode until the fault is corrected and all gaps in redo log files are resolved. When all gaps are resolved, the primary database automatically resumes operating in maximum availability mode.
This mode ensures that no data loss will occur if the primary database fails, but only if a second fault does not prevent a complete set of redo data from being sent from the primary database to at least one standby database.
Like maximum protection mode, the maximum availability mode requires that you:
Configure standby redo log files on at least one standby database.
Set the SYNC, LGWR, and AFFIRM attributes of the LOG_ARCHIVE_DEST_n parameter for at least 1 standby database.
1.3 Maximum Performance Mode
This protection mode (the default) provides the highest level of data protection that is possible without affecting the performance of the primary database. This is accomplished by allowing a transaction to commit as soon as the redo data needed to recover that transaction is written to the local online redo log. The primary database’s redo data stream is also written to at least one standby database, but that redo stream is written asynchronously with respect to the commitment of the transactions that create the redo data.
When network links with sufficient bandwidth are used, this mode provides a level of data protection that approaches that of maximum availability mode with minimal impact on primary database performance.
The maximum performance mode enables you to either set the LGWR and ASYNC attributes, or set the ARCH attribute on the LOG_ARCHIVE_DEST_n parameter for the standby database destination. If the primary database fails, you can reduce the amount of data that is not received on the standby destination by setting the LGWR and ASYNC attributes.

在了解DG以上三种数据库保护模式后，下面说明一下如何设置这三种数据保护模式：
Step 1   Configure the LOG_ARCHIVE_DEST_n parameters on the primary database
On the primary database, configure the LOG_ARCHIVE_DEST_n parameter attributes appropriately. Each of the Data Guard data protection modes requires that at least one standby database in the configuration meet the minimum set of requirements listed in Table 5-2.
Table 5-2 Minimum Requirements for Data Protection Modes

	Maximum Protection	Maximum Availability	Maximum Performance
Redo archival process	LGWR	LGWR	LGWR or ARCH
Network transmission mode	SYNC	SYNC	SYNC or ASYNC when using LGWR process. SYNC if using ARCH process
Disk write option	AFFIRM	AFFIRM	AFFIRM or NOAFFIRM
Standby redo log required?	Yes	Yes	No, but it is recommended

Note:
Oracle recommends that a Data Guard configuration that is running in maximum protection mode contains at least two standby databases that meet the requirements listed in Table 5-2. That way, the primary database can continue processing if one of the standby databases cannot receive redo data from the primary database.
The following example shows how to configure the maximum availability mode:

SQL> ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=PROD
  2> OPTIONAL LGWR SYNC AFFIRM
  3> VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE)
  4> DB_UNIQUE_NAME=PROD';

If they are not already specified in the SPFILE, you should also specify unique names with the DB_UNIQUE_NAME initialization parameter and list all databases on the LOG_ARCHIVE_CONFIG parameter with the DG_CONFIG attribute. For example:

SQL> ALTER SYSTEM SET LOG_ARCHIVE_CONFIG='DG_CONFIG=(PROD,SBDB)';

This will enable the dynamic addition of a standby database to a Data Guard configuration that has a Real Application Clusters primary database running in either maximum protection or maximum availability mode.
Step 1 If you are upgrading the protection mode, perform this step.
Perform this step only if you are upgrading the protection mode (for example, from maximum performance to maximum availability mode). Otherwise, go to Step 3.
Assume this example is upgrading the Data Guard configuration from the maximum performance mode to the maximum availability mode. Shut down the primary database and restart it in mounted mode:

SQL> SHUTDOWN IMMEDIATE;
SQL> STARTUP MOUNT;

For a Real Application Clusters database, shut down all of the primary instances but start and mount only one primary instance.
Step 2 Set the data protection mode.
To specify a data protection mode, issue the SQL ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE {PROTECTION | AVAILABILITY | PERFORMANCE} statement on the primary database. For example, the following statement specifies the maximum availability mode:

SQL> ALTER DATABASE SET STANDBY DATABASE TO MAXIMIZE AVAILABILITY;

Step 3 Open the primary database.
If you performed Step 1 to upgrade the protection mode, open the database:

SQL> ALTER DATABASE OPEN;

If you are downgrading the protection mode, the database will already be open.
Step 4 Configure the LOG_ARCHIVE_DEST_n parameters on standby databases.
On the standby databases, configure the LOG_ARCHIVE_DEST_n parameter attributes so the configuration can continue to operate in the new protection mode after a switchover. For example:

SQL> ALTER SYSTEM SET LOG_ARCHIVE_DEST_2='SERVICE=boston
  2> OPTIONAL LGWR SYNC AFFIRM
  3> VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE)
  4> DB_UNIQUE_NAME=boston';

Step 5 Confirm the configuration is operating in the new protection mode.
Query the V$DATABASE view to confirm the Data Guard configuration is operating in the new protection mode. For example:

SQL> SELECT PROTECTION_MODE, PROTECTION_LEVEL FROM V$DATABASE;
PROTECTION_MODE                   PROTECTION_LEVEL
---------------------             ---------------------
MAXIMUM AVAILABILITY              MAXIMUM AVAILABILITY

以上结合官档简要说明了DG的数据保护模式，后期会继续更新相关内容，敬请期待！

在前三篇中我们解释了DG的基础知识及相关概念和原理，从这篇开始会从实战角度去演示物理逻辑备库的搭建、主备库切换、主备间库数据同步监控以及优化。本篇我们主要结合官方文档演示物理备库的创建过程。

在正式开始演示物理备库创建过程前，先描述一下测试环境：

Oracle VM VirtualBox + Oracle Linux 5.8
Host Name: 10g.localdomain
IP Address: 192.168.56.10
Oracle 10.2.0.5.12 DB + File System
Primary DB Name and Instance Nname: PROD
Standby DB Instance Nname: SBDB

注：以下演示过程由于是在笔记本虚拟机上进行测试，因此硬件虚拟资源有限，所以选择将主备库放在同一台虚拟主机上演示物理备库的搭建过程，但这并不影响演示过程及测试结果。

0.主备库准备工作

0.0 Create a primary DB with DB_NAME and SID PROD using DBCA
0.1 Enable PROD with archived mode using FRA
0.2 Add listeners and configure service name for the primary and standby databases
    netca --- Add Listener and Configure Service Name (PROD + SBDB)

1.主库操作过程及步骤

1.1 打开主库归档
SYS@PROD> ARCHIVE LOG LIST
Database log mode              Archive Mode
Automatic archival             Enabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     7
Next log sequence to archive   9
Current log sequence           9
 
1.2 开启主库闪回
SYS@PROD> SELECT FLASHBACK_ON FROM V$DATABASE;
 
FLASHBACK_ON
------------------
YES
 
1.3 强制主库写日志
SYS@PROD> ALTER DATABASE FORCE LOGGING;
 
Database altered.
 
1.4 配置Standby Redo Log
Step 1 确认主库redo log大小使其备库上保持一致
Step 2 决定standby redo log数目，计算方法：(maximum number of logfiles for each thread + 1) * maximum number of threads
SYS@PROD> SELECT L.GROUP#,L.THREAD#,L.MEMBERS,F.MEMBER,BYTES/1024/1024,L.STATUS FROM V$LOG L,V$LOGFILE F WHERE L.GROUP#=F.GROUP#;
 
    GROUP#    THREAD#    MEMBERS MEMBER                                             BYTES/1024/1024 STATUS
---------- ---------- ---------- -------------------------------------------------- --------------- ----------------
         1          1          1 /u01/app/oracle/oradata/PROD/redo01.log                         50 CURRENT
         2          1          1 /u01/app/oracle/oradata/PROD/redo02.log                         50 INACTIVE
         3          1          1 /u01/app/oracle/oradata/PROD/redo03.log                         50 INACTIVE
 
SYS@PROD> ALTER DATABASE ADD STANDBY LOGFILE GROUP 4 ('/u01/app/oracle/oradata/PROD/redo04.log') SIZE 50M;
 
Database altered.
 
SYS@PROD> ALTER DATABASE ADD STANDBY LOGFILE GROUP 5 ('/u01/app/oracle/oradata/PROD/redo05.log') SIZE 50M;
 
Database altered.
 
SYS@PROD> ALTER DATABASE ADD STANDBY LOGFILE GROUP 6 ('/u01/app/oracle/oradata/PROD/redo06.log') SIZE 50M;
 
Database altered.
 
SYS@PROD> ALTER DATABASE ADD STANDBY LOGFILE GROUP 7 ('/u01/app/oracle/oradata/PROD/redo07.log') SIZE 50M;
 
Database altered.
 
1.5 查看已添加成功的Standby Redo Log
SYS@PROD> 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
         7          0          0 YES UNASSIGNED
 
SYS@PROD> select * from v$logfile;
 
    GROUP# STATUS  TYPE    MEMBER                                             IS_
---------- ------- ------- -------------------------------------------------- ---
         1         ONLINE  /u01/app/oracle/oradata/PROD/redo01.log            NO
         2         ONLINE  /u01/app/oracle/oradata/PROD/redo02.log            NO
         3         ONLINE  /u01/app/oracle/oradata/PROD/redo03.log            NO
         4         STANDBY /u01/app/oracle/oradata/PROD/redo04.log            NO
         5         STANDBY /u01/app/oracle/oradata/PROD/redo05.log            NO
         6         STANDBY /u01/app/oracle/oradata/PROD/redo06.log            NO
         7         STANDBY /u01/app/oracle/oradata/PROD/redo07.log            NO
 
1.6 设置主库初始化参数
[oracle@10g dbs]$ cat initPROD.ora 
PROD.__db_cache_size=427819008
PROD.__java_pool_size=4194304
PROD.__large_pool_size=4194304
PROD.__shared_pool_size=155189248
PROD.__streams_pool_size=0
*.audit_file_dest='/u01/app/oracle/admin/PROD/adump'
*.background_dump_dest='/u01/app/oracle/admin/PROD/bdump'
*.compatible='10.2.0.5.0'
*.control_files='/u01/app/oracle/oradata/PROD/control01.ctl','/u01/app/oracle/oradata/PROD/control02.ctl','/u01/app/oracle/oradata/PROD/control03.ctl'
*.core_dump_dest='/u01/app/oracle/admin/PROD/cdump'
*.db_block_size=8192
*.db_domain=''
*.db_file_multiblock_read_count=16
*.db_name='PROD'
*.db_recovery_file_dest='/u01/app/oracle/flash_recovery_area'
*.db_recovery_file_dest_size=2147483648
*.job_queue_processes=10
*.open_cursors=300
*.pga_aggregate_target=199229440
*.processes=150
*.remote_login_passwordfile='EXCLUSIVE'
*.sga_target=597688320
*.undo_management='AUTO'
*.undo_tablespace='UNDOTBS1'
*.user_dump_dest='/u01/app/oracle/admin/PROD/udump'
###### Add Primary DB Initialization Parameters ######
DB_UNIQUE_NAME=PROD
LOG_ARCHIVE_CONFIG='DG_CONFIG=(PROD,SBDB)'
LOG_ARCHIVE_DEST_1=
 'LOCATION=USE_DB_RECOVERY_FILE_DEST
  VALID_FOR=(ALL_LOGFILES,ALL_ROLES)
  DB_UNIQUE_NAME=PROD'
LOG_ARCHIVE_DEST_2=
 'SERVICE=SBDB LGWR ASYNC
  VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) 
  DB_UNIQUE_NAME=SBDB'
LOG_ARCHIVE_DEST_STATE_1=ENABLE
LOG_ARCHIVE_DEST_STATE_2=ENABLE
REMOTE_LOGIN_PASSWORDFILE=EXCLUSIVE
LOG_ARCHIVE_FORMAT=%t_%s_%r.arc
LOG_ARCHIVE_MAX_PROCESSES=8
FAL_SERVER=SBDB
FAL_CLIENT=PROD
DB_FILE_NAME_CONVERT='SBDB','PROD'
LOG_FILE_NAME_CONVERT='SBDB','PROD'
STANDBY_FILE_MANAGEMENT=AUTO
关于主库初始化参数需要说明的几点：
①主库初始化参数中应去掉相关的shared server参数；
②参数文件中自###### Add Standby DB Initialization Parameters ######到文末内容粘贴官档修改；
③LOG_ARCHIVE_DEST_n定义了主库归档日志位置、主备库redo传输方式；
④DB_FILE_NAME_CONVERT及LOG_FILE_NAME_CONVERT定义了主备库数据文件及日志文件转换规则；
⑤STANDBY_FILE_MANAGEMENT定义了备库文件的管理方式。
 
1.7使用新初始化参数文件启动主库到mount状态使用RMAN冷备主库
SYS@PROD> alter system checkpoint;
 
System altered.
 
SYS@PROD> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
 
SYS@PROD> create spfile from pfile;
 
File created.
 
SYS@PROD> startup mount;
ORACLE instance started.
 
Total System Global Area  599785472 bytes
Fixed Size                  2098112 bytes
Variable Size             163580992 bytes
Database Buffers          427819008 bytes
Redo Buffers                6287360 bytes
Database mounted.
 
[oracle@10g ~]$ rman target /
 
Recovery Manager: Release 10.2.0.5.0 - Production on Thu Oct 24 11:17:12 2013
 
Copyright (c) 1982, 2007, Oracle.  All rights reserved.
 
connected to target database: PROD (DBID=241479471, not open)
 
RMAN> backup as compressed backupset full database plus archivelog delete input;
 
Starting backup at 24-OCT-13
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=159 devtype=DISK
specification does not match any archive log in the recovery catalog
backup cancelled because all files were skipped
Finished backup at 24-OCT-13
 
Starting backup at 24-OCT-13
using channel ORA_DISK_1
channel ORA_DISK_1: starting compressed full datafile backupset
channel ORA_DISK_1: specifying datafile(s) in backupset
input datafile fno=00001 name=/u01/app/oracle/oradata/PROD/system01.dbf
input datafile fno=00002 name=/u01/app/oracle/oradata/PROD/undotbs01.dbf
input datafile fno=00003 name=/u01/app/oracle/oradata/PROD/sysaux01.dbf
input datafile fno=00004 name=/u01/app/oracle/oradata/PROD/users01.dbf
channel ORA_DISK_1: starting piece 1 at 24-OCT-13
channel ORA_DISK_1: finished piece 1 at 24-OCT-13
piece handle=/u01/app/oracle/flash_recovery_area/PROD/backupset/2013_10_24/o1_mf_nnndf_TAG20131024T111756_96k4c4j8_.bkp tag=TAG20131024T111756 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:15
channel ORA_DISK_1: starting compressed full datafile backupset
channel ORA_DISK_1: specifying datafile(s) in backupset
including current control file in backupset
including current SPFILE in backupset
channel ORA_DISK_1: starting piece 1 at 24-OCT-13
channel ORA_DISK_1: finished piece 1 at 24-OCT-13
piece handle=/u01/app/oracle/flash_recovery_area/PROD/backupset/2013_10_24/o1_mf_ncsnf_TAG20131024T111756_96k4cnys_.bkp tag=TAG20131024T111756 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:02
Finished backup at 24-OCT-13
 
Starting backup at 24-OCT-13
using channel ORA_DISK_1
specification does not match any archive log in the recovery catalog
backup cancelled because all files were skipped
Finished backup at 24-OCT-13
注：由于主库使用FRA并开启闪回功能，因此归档及备份文件都放在FRA。
 
1.8 创建备库控制文件
SYS@PROD> ALTER DATABASE CREATE STANDBY CONTROLFILE AS '/home/oracle/SBDB.ctl';
 
Database altered.
 
---到此主库配置完成。

2.物理备库创建过程及步骤

2.1在备库上创建与主库相同的目录结构
[oracle@10g ~]$ mkdir -p /u01/app/oracle/admin/SBDB/{a,b,c,u}dump
[oracle@10g ~]$ mkdir -p /u01/app/oracle/oradata/SBDB
[oracle@10g ~]$ mkdir -p /u01/app/oracle/flash_recovery_area/SBDB/archivelog
[oracle@10g ~]$ mkdir -p /u01/app/oracle/flash_recovery_area/SBDB/backupset
[oracle@10g ~]$ mkdir -p /u01/app/oracle/flash_recovery_area/SBDB/flashback
 
2.2拷贝主库密码文件到备库
[oracle@10g dbs]$ pwd
/u01/app/oracle/product/10.2.0/db_1/dbs
[oracle@10g dbs]$ cp orapwPROD orapwSBDB
 
2.3设置备库初始化参数文件
Step 1 拷贝主库初始化参数文件到备库
Step 2 修改参数文件如下
[oracle@10g dbs]$ cat initSDBD.ora 
SBDB.__db_cache_size=427819008
SBDB.__java_pool_size=4194304
SBDB.__large_pool_size=4194304
SBDB.__shared_pool_size=155189248
SBDB.__streams_pool_size=0
*.audit_file_dest='/u01/app/oracle/admin/SBDB/adump'
*.background_dump_dest='/u01/app/oracle/admin/SBDB/bdump'
*.compatible='10.2.0.5.0'
*.control_files='/u01/app/oracle/oradata/SBDB/control01.ctl','/u01/app/oracle/oradata/SBDB/control02.ctl','/u01/app/oracle/oradata/SBDB/control03.ctl'
*.core_dump_dest='/u01/app/oracle/admin/SBDB/cdump'
*.db_block_size=8192
*.db_domain=''
*.db_file_multiblock_read_count=16
*.db_name='PROD'
*.db_recovery_file_dest='/u01/app/oracle/flash_recovery_area'
*.db_recovery_file_dest_size=2147483648
*.job_queue_processes=10
*.open_cursors=300
*.pga_aggregate_target=199229440
*.processes=150
*.remote_login_passwordfile='EXCLUSIVE'
*.sga_target=597688320
*.undo_management='AUTO'
*.undo_tablespace='UNDOTBS1'
*.user_dump_dest='/u01/app/oracle/admin/SBDB/udump'
###### Add Standby DB Initialization Parameters ######
DB_UNIQUE_NAME=SBDB
LOG_ARCHIVE_CONFIG='DG_CONFIG=(PROD,SBDB)'
DB_FILE_NAME_CONVERT='PROD','SBDB'
LOG_FILE_NAME_CONVERT='PROD','SBDB'
LOG_ARCHIVE_FORMAT=log%t_%s_%r.arc
LOG_ARCHIVE_DEST_1=
 'LOCATION=USE_DB_RECOVERY_FILE_DEST
  VALID_FOR=(ALL_LOGFILES,ALL_ROLES) 
  DB_UNIQUE_NAME=SBDB'
LOG_ARCHIVE_DEST_2=
 'SERVICE=PROD LGWR ASYNC
  VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) 
  DB_UNIQUE_NAME=PROD'
LOG_ARCHIVE_DEST_STATE_1=ENABLE
LOG_ARCHIVE_DEST_STATE_2=ENABLE
REMOTE_LOGIN_PASSWORDFILE=EXCLUSIVE
STANDBY_FILE_MANAGEMENT=AUTO
FAL_SERVER=PROD
FAL_CLIENT=SBDB
关于备库初始化参数需要说明的几点：
①将主库初始化参数文件拷贝改名后，使用vi打开将自###### Add Primary DB Initialization Parameters ######到文末删除，使用全局替换将除*.db_name='PROD'外所有PROD换成SBDB；
②参数文件中自###### Add Standby DB Initialization Parameters ######到文末内容粘贴官档修改；
③LOG_ARCHIVE_DEST_n定义了主库归档日志位置、主备库redo传输方式；
④DB_FILE_NAME_CONVERT及LOG_FILE_NAME_CONVERT定义了主备库数据文件及日志文件转换规则；
⑤STANDBY_FILE_MANAGEMENT定义了备库文件的管理方式。
 
2.4启动备库到nomount将主库RMAN全备恢复到备库上
SYS@SBDB> create spfile from pfile;
 
File created.
 
SYS@SBDB> startup nomount;
ORACLE instance started.
 
Total System Global Area  599785472 bytes
Fixed Size                  2098112 bytes
Variable Size             163580992 bytes
Database Buffers          427819008 bytes
Redo Buffers                6287360 bytes
 
[oracle@10g ~]$ export ORACLE_SID=SBDB
[oracle@10g ~]$ rman target /
 
Recovery Manager: Release 10.2.0.5.0 - Production on Thu Oct 24 11:30:24 2013
 
Copyright (c) 1982, 2007, Oracle.  All rights reserved.
 
connected to target database: PROD (not mounted)
 
RMAN> restore controlfile from '/home/oracle/SBDB.ctl';
 
Starting restore at 24-OCT-13
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=156 devtype=DISK
 
channel ORA_DISK_1: copied control file copy
output filename=/u01/app/oracle/oradata/SBDB/control01.ctl
output filename=/u01/app/oracle/oradata/SBDB/control02.ctl
output filename=/u01/app/oracle/oradata/SBDB/control03.ctl
Finished restore at 24-OCT-13
 
RMAN> run {
2> allocate channel c1 type disk;
3> set newname for datafile 1 to '/u01/app/oracle/oradata/SBDB/system01.dbf'; 
4> set newname for datafile 2 to '/u01/app/oracle/oradata/SBDB/undotbs01.dbf';
5> set newname for datafile 3 to '/u01/app/oracle/oradata/SBDB/sysaux01.dbf';
6> set newname for datafile 4 to '/u01/app/oracle/oradata/SBDB/users01.dbf';
7> set newname for tempfile 1 to '/u01/app/oracle/oradata/SBDB/temp01.dbf';
8> released channel c1;
9> }
 
allocated channel: c1
channel c1: sid=156 devtype=DISK
 
executing command: SET NEWNAME
 
executing command: SET NEWNAME
 
executing command: SET NEWNAME
 
executing command: SET NEWNAME
 
executing command: SET NEWNAME
released channel: c1
 
RMAN> restore database;
 
Starting restore at 24-OCT-13
Starting implicit crosscheck backup at 24-OCT-13
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=156 devtype=DISK
Crosschecked 11 objects
Finished implicit crosscheck backup at 24-OCT-13
 
Starting implicit crosscheck copy at 24-OCT-13
using channel ORA_DISK_1
Crosschecked 1 objects
Finished implicit crosscheck copy at 24-OCT-13
 
searching for all files in the recovery area
cataloging files...
no files cataloged
 
using channel ORA_DISK_1
 
channel ORA_DISK_1: starting datafile backupset restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
restoring datafile 00001 to /u01/app/oracle/oradata/SBDB/system01.dbf
restoring datafile 00002 to /u01/app/oracle/oradata/SBDB/undotbs01.dbf
restoring datafile 00003 to /u01/app/oracle/oradata/SBDB/sysaux01.dbf
restoring datafile 00004 to /u01/app/oracle/oradata/SBDB/users01.dbf
channel ORA_DISK_1: reading from backup piece /u01/app/oracle/flash_recovery_area/PROD/backupset/2013_10_24/o1_mf_nnndf_TAG20131024T111756_96k4c4j8_.bkp
channel ORA_DISK_1: restored backup piece 1
piece handle=/u01/app/oracle/flash_recovery_area/PROD/backupset/2013_10_24/o1_mf_nnndf_TAG20131024T111756_96k4c4j8_.bkp tag=TAG20131024T111756
channel ORA_DISK_1: restore complete, elapsed time: 00:00:35
Finished restore at 24-OCT-13
关于将主库RMAN全备恢复到备库上的几点说明：
①由于主库使用RMAN做冷全备份，因此在备库上使用RMAN恢复时只需要执行restore；
②由于主库数据文件等命名与备库不同，因此在备库上使用RMAN恢复时需要在RUN块中执行set newname for命令转换；
③如果不清楚RMAN异机恢复过程建议查阅官方文档。
 
2.5检查备库是否恢复完成
SYS@PROD> select * from v$log;
 
    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
         1          1         13   52428800          1 YES INACTIVE                183935 24-OCT-13
         3          1         12   52428800          1 YES INACTIVE                183375 24-OCT-13
         2          1         14   52428800          1 NO  CURRENT                 183951 24-OCT-13
 
SYS@SBDB> select * from v$log;
 
    GROUP#    THREAD#  SEQUENCE#      BYTES    MEMBERS ARC STATUS           FIRST_CHANGE# FIRST_TIM
---------- ---------- ---------- ---------- ---------- --- ---------------- ------------- ---------
         1          1         13   52428800          1 YES INACTIVE                183935 24-OCT-13
         3          1         12   52428800          1 YES INACTIVE                183375 24-OCT-13
         2          1         14   52428800          1 NO  CURRENT                 183951 24-OCT-13
 
2.6检查此时主备库监听状态
[oracle@10g ~]$ lsnrctl status
 
LSNRCTL for Linux: Version 10.2.0.5.0 - Production on 24-OCT-2013 12:08:45
 
Copyright (c) 1991, 2010, Oracle.  All rights reserved.
 
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=10g.localdomain)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 10.2.0.5.0 - Production
Start Date                24-OCT-2013 10:39:05
Uptime                    0 days 1 hr. 29 min. 39 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   /u01/app/oracle/product/10.2.0/db_1/network/admin/listener.ora
Listener Log File         /u01/app/oracle/product/10.2.0/db_1/network/log/listener.log
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=10g.localdomain)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC0)))
Services Summary...
Service "PLSExtProc" has 1 instance(s).
  Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "PROD" has 1 instance(s).
  Instance "PROD", status READY, has 1 handler(s) for this service...
Service "PROD_XPT" has 1 instance(s).
  Instance "PROD", status READY, has 1 handler(s) for this service...
Service "SBDB" has 1 instance(s).
  Instance "SBDB", status READY, has 1 handler(s) for this service...
Service "SBDB_XPT" has 1 instance(s).
  Instance "SBDB", status READY, has 1 handler(s) for this service...
The command completed successfully
 
2.7启动备库应用redo
SYS@SBDB> select instance_name,status from v$instance;
 
INSTANCE_NAME    STATUS
---------------- ------------
SBDB             MOUNTED
 
SYS@SBDB> select name,open_mode from v$database;
 
NAME      OPEN_MODE
--------- ----------
PROD      MOUNTED
 
SYS@SBDB> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION PARALLEL 2;
 
Database altered.
 
---到此备库创建完成。

3.打开主库查看主备库日志同步及备库日志应用情况

3.1检查备库已归档日志情况
SYS@SBDB> SELECT SEQUENCE#, FIRST_TIME, NEXT_TIME FROM V$ARCHIVED_LOG ORDER BY SEQUENCE#;
 
 SEQUENCE# FIRST_TIM NEXT_TIME
---------- --------- ---------
        14 24-OCT-13 24-OCT-13
        15 24-OCT-13 24-OCT-13
        16 24-OCT-13 24-OCT-13
        17 24-OCT-13 24-OCT-13
        18 24-OCT-13 24-OCT-13
        19 24-OCT-13 24-OCT-13
        20 24-OCT-13 24-OCT-13
        21 24-OCT-13 24-OCT-13
        22 24-OCT-13 24-OCT-13
        23 24-OCT-13 24-OCT-13
        24 24-OCT-13 24-OCT-13
        25 24-OCT-13 24-OCT-13
        26 24-OCT-13 24-OCT-13
        27 24-OCT-13 24-OCT-13
        28 24-OCT-13 24-OCT-13
        29 24-OCT-13 24-OCT-13
        30 24-OCT-13 24-OCT-13
        31 24-OCT-13 24-OCT-13
        32 24-OCT-13 24-OCT-13
        33 24-OCT-13 24-OCT-13
        34 24-OCT-13 24-OCT-13
        35 24-OCT-13 24-OCT-13
        36 24-OCT-13 24-OCT-13
        37 24-OCT-13 24-OCT-13
        38 24-OCT-13 24-OCT-13
        39 24-OCT-13 24-OCT-13
        40 24-OCT-13 24-OCT-13
        41 24-OCT-13 24-OCT-13
        42 24-OCT-13 24-OCT-13
 
29 rows selected.
 
3.2主库手动切换日志（可以多切换几组）
SYS@PROD> alter database open;
 
Database altered.
 
3.3检查备库新日志归档情况
SYS@SBDB> SELECT SEQUENCE#, FIRST_TIME, NEXT_TIME FROM V$ARCHIVED_LOG ORDER BY SEQUENCE#;
 
 SEQUENCE# FIRST_TIM NEXT_TIME
---------- --------- ---------
        14 24-OCT-13 24-OCT-13
        15 24-OCT-13 24-OCT-13
        16 24-OCT-13 24-OCT-13
        17 24-OCT-13 24-OCT-13
        18 24-OCT-13 24-OCT-13
        19 24-OCT-13 24-OCT-13
        20 24-OCT-13 24-OCT-13
        21 24-OCT-13 24-OCT-13
        22 24-OCT-13 24-OCT-13
        23 24-OCT-13 24-OCT-13
        24 24-OCT-13 24-OCT-13
        25 24-OCT-13 24-OCT-13
        26 24-OCT-13 24-OCT-13
        27 24-OCT-13 24-OCT-13
        28 24-OCT-13 24-OCT-13
        29 24-OCT-13 24-OCT-13
        30 24-OCT-13 24-OCT-13
        31 24-OCT-13 24-OCT-13
        32 24-OCT-13 24-OCT-13
        33 24-OCT-13 24-OCT-13
        34 24-OCT-13 24-OCT-13
        35 24-OCT-13 24-OCT-13
        36 24-OCT-13 24-OCT-13
        37 24-OCT-13 24-OCT-13
        38 24-OCT-13 24-OCT-13
        39 24-OCT-13 24-OCT-13
        40 24-OCT-13 24-OCT-13
        41 24-OCT-13 24-OCT-13
        42 24-OCT-13 24-OCT-13
        43 24-OCT-13 24-OCT-13
 
30 rows selected.
 
3.4检查备库新日志应用情况
SYS@SBDB> SELECT SEQUENCE#,APPLIED FROM V$ARCHIVED_LOG ORDER BY SEQUENCE#;
 
 SEQUENCE# APP
---------- ---
        14 YES
        15 YES
        16 YES
        17 YES
        18 YES
        19 YES
        20 YES
        21 YES
        22 YES
        23 YES
        24 YES
        25 YES
        26 YES
        27 YES
        28 YES
        29 YES
        30 YES
        31 YES
        32 YES
        33 YES
        34 YES
        35 YES
        36 YES
        37 YES
        38 YES
        39 YES
        40 YES
        41 YES
        42 YES
        43 YES
 
30 rows selected.
 
3.5检查主备库当前状态
SYS@PROD> select DATABASE_ROLE,SWITCHOVER_STATUS from v$database;
 
DATABASE_ROLE    SWITCHOVER_STATUS
---------------- --------------------
PRIMARY          TO STANDBY
 
SYS@SBDB> select DATABASE_ROLE,SWITCHOVER_STATUS from v$database;
 
DATABASE_ROLE    SWITCHOVER_STATUS
---------------- --------------------
PHYSICAL STANDBY TO PRIMARY
 
---到此主备数据库日志传输及备库日志应用均正常。

该篇结合官方文档演示了物理备库的创建过程，为了使该演示过程简介清晰，未将主备库日志同步及备库日志应用情况时的alert.log贴出，但在此不得不指出，主备库alert.log中相关信息的重要性，很多时候我们在配置主备库过程中难免会出现错误，此时就需要仔细查阅主备库alert.log日志中的相关信息才能定位错误发生的原因。对于该篇中的演示过程，虽然我们是在同一太主机上进行，但是这和我们在两天机器上演示该过程并没有本质的变化，唯一不同的操作是拷贝文件及恢复出备库都是在异机上操作而已。下一篇将会介绍物理主备库在两种情况下的角色转换，敬请期待！