Skip to content

Oracle 11g OCM之Rman 新特性

《Oracle® Database Backup and Recovery User’s Guide》11g Release 1 (11.1)

1.11gRMAN新特性概要（R1）

*Interfile backup parallelism
*Faster backup compression
*Better security
*Active database duplication
Improved handling of long-term backups
*Backup failover for archived redo logs
*Archived redo log deletion policy enhancements
*Recovery catalog enhancements
Undo backup optimization
Block media performance improvements
Block change support for standby databases
Improved RMAN scripting
Backup of read-only transportable tablespaces

本文对重点部分（带*）进行讲解

2.Interfile backup parallelism 并行多段备份

2.1 多段备份（Multisection backup）

BACKUP SECTION SIZE …. TABLESPACE tbs_name/DATAFILE N;

从11gr1开始oracle的在rman的backup中增加了section参数，可以通过section参数指定备份对象（表空间，数据
文件）生成的备份片按照section size指定的单位生成多个备份段。相对10g以前的版本，该特性解决了ORACLE对大
数据量的单数据文件的备份提供支持，并且支持单个数据文件的并行备份，提高备份速度。

在backup命令中，section size不可以和maxsize一起使用，每个数据文件最多可以有256个section，如果指定的
section值超过了datafile的实际大小，Rman不会使用Section指定的size进行备份，会直接进行整个datafile的
直接备份.

例1.进行单个表空间的分段备份

SQL> col file_name for a40
SQL> col tablespace_name for a30
SQL> select file_name,tablespace_name，bytes/1024/1024 from dba_data_files where tablespace_name=’CAT_TBS’;
FILE_NAME                                TABLESPACE_NAME                BYTES/1024/1024
—————————————- —————————— —————
/data01/cat_tbs01.dbf                    CAT_TBS                                     20

对CAT_TBS表空间进行分段备份：

[oracle@luda 22:51:54|~]rman target / catalog rman1/oracle@luda

Recovery Manager: Release 11.2.0.1.0 – Production on Thu Nov 22 22:52:06 2012

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

connected to target database: LUDA (DBID=518309061)
connected to recovery catalog database

RMAN> backup section size 10M tablespace cat_tbs;

Starting backup at 22-NOV-12
starting full resync of recovery catalog
full resync complete
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=201 device type=DISK
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 1 through 1280
channel ORA_DISK_1: starting piece 1 at 22-NOV-12
channel ORA_DISK_1: finished piece 1 at 22-NOV-12
piece handle=/oracle/product/11.2/dbs/06nqvsil_1_1 tag=TAG20121122T225309 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:03
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 1281 through 2560
channel ORA_DISK_1: starting piece 2 at 22-NOV-12
channel ORA_DISK_1: finished piece 2 at 22-NOV-12
piece handle=/oracle/product/11.2/dbs/06nqvsil_2_1 tag=TAG20121122T225309 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 22-NOV-12

对/data01/cat_tbs01.dbf 进行分段备份：

RMAN> backup section size 5M datafile ‘/data01/cat_tbs01.dbf’;

Starting backup at 22-NOV-12
using channel ORA_DISK_1
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 1 through 640
channel ORA_DISK_1: starting piece 1 at 22-NOV-12
channel ORA_DISK_1: finished piece 1 at 22-NOV-12
piece handle=/oracle/product/11.2/dbs/08nqvspu_1_1 tag=TAG20121122T225702 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 641 through 1280
channel ORA_DISK_1: starting piece 2 at 22-NOV-12
channel ORA_DISK_1: finished piece 2 at 22-NOV-12
piece handle=/oracle/product/11.2/dbs/08nqvspu_2_1 tag=TAG20121122T225702 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 1281 through 1920
channel ORA_DISK_1: starting piece 3 at 22-NOV-12
channel ORA_DISK_1: finished piece 3 at 22-NOV-12
piece handle=/oracle/product/11.2/dbs/08nqvspu_3_1 tag=TAG20121122T225702 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 1921 through 2560
channel ORA_DISK_1: starting piece 4 at 22-NOV-12
channel ORA_DISK_1: finished piece 4 at 22-NOV-12
piece handle=/oracle/product/11.2/dbs/08nqvspu_4_1 tag=TAG20121122T225702 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 22-NOV-12

指定section size 大于/data01/cat_tbs01.dbf的大小的值进行备份：

RMAN> backup section size 30M datafile ‘/data01/cat_tbs01.dbf’;

Starting backup at 22-NOV-12
using channel ORA_DISK_1
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
channel ORA_DISK_1: starting piece 1 at 22-NOV-12
channel ORA_DISK_1: finished piece 1 at 22-NOV-12
piece handle=/oracle/product/11.2/dbs/0cnqvss5_1_1 tag=TAG20121122T225813 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 22-NOV-12

可以发现如果section size大于备份的datafile的大小，那么数据库将忽略section的设置。

2.2 并行（parallel）的进行多段（section）备份

RMAN>   run {
2>         allocate channel c1 device type disk format ‘/data01/rman/OMR_%U’;
3>         allocate channel c2 device type disk format ‘/data01/rman/OMR_%U’;
4>         backup section size 10M tablespace CAT_TBS;
5>       }

released channel: ORA_DISK_1
allocated channel: c1
channel c1: SID=201 device type=DISK

allocated channel: c2
channel c2: SID=393 device type=DISK

Starting backup at 22-NOV-12
channel c1: starting full datafile backup set
channel c1: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 1 through 1280
channel c1: starting piece 1 at 22-NOV-12
channel c2: starting full datafile backup set
channel c2: specifying datafile(s) in backup set
input datafile file number=00006 name=/data01/cat_tbs01.dbf
backing up blocks 1281 through 2560
channel c2: starting piece 2 at 22-NOV-12
channel c1: finished piece 1 at 22-NOV-12
piece handle=/data01/rman/OMR_0dnqvt43_1_1 tag=TAG20121122T230227 comment=NONE
channel c1: backup set complete, elapsed time: 00:00:02
channel c2: finished piece 2 at 22-NOV-12
piece handle=/data01/rman/OMR_0dnqvt43_2_1 tag=TAG20121122T230227 comment=NONE
channel c2: backup set complete, elapsed time: 00:00:01
Finished backup at 22-NOV-12
released channel: c1
released channel: c2

RMAN> list backup of tablespace cat_tbs;
略。。。
Backup Set Copy #1 of backup set 211
Device Type Elapsed Time Completion Time Compressed Tag
———– ———— ————— ———- —
DISK        00:00:01     22-NOV-12       NO         TAG20121122T230227

List of Backup Pieces for backup set 211 Copy #1
BP Key  Pc# Status      Piece Name
——- — ———– ———-
213     1   AVAILABLE   /data01/rman/OMR_0dnqvt43_1_1
214     2   AVAILABLE   /data01/rman/OMR_0dnqvt43_2_1

3 Rman备份压缩算法

在oracle 10g的版本中为Rman提供BZIP2的压缩算法，从11gR1版本开始oracle提供全新的算法ZLIB，两者的主要差异
在于：
1.BZIP2的压缩比要优于ZLIB
2.ZLIB的压缩速度要快于BZIP2
所以对于BZIP2和ZLIB的选择相对来讲就是对备份的速度和备份占用空间的抉择。

备注：

从11g R2开始，Oracle Advanced Compression Option统一了部分压缩算法级别(compression algorithm le
vels)，可同时适用于table data, Data Pump exports 和 RMAN 备份。新的压缩级别分为BASIC、LOW、MEDIUM 和H
IGH.

column ALGORITHM_NAME format a7
column INITIAL_RELEASE format a10
column TERMINAL_RELEASE format a10
column ALGORITHM_DESCRIPTION format a45
select ALGORITHM_NAME, INITIAL_RELEASE, TERMINAL_RELEASE, ALGORITHM_DESCRIPTION, IS_VALID, REQUIRES_ACO from V$RMAN_COMPRESSION_ALGORITHM;

ALGORIT INITIAL_RE TERMINAL_R ALGORITHM_DESCRIPTION                         IS_ REQ
——- ———- ———- ——————————————— — —
BASIC   10.0.0.0.0            good compression ratio                        YES NO
LOW     11.2.0.0.0            maximum possible compression speed            YES YES
MEDIUM  11.2.0.0.0            balance between speed and compression ratio   YES YES
HIGH    11.2.0.0.0            maximum possible compression ratio            YES YES

例：

3.1 更改压缩算法设置(11gR1版本）

RMAN> CONFIGURE COMPRESSION ALGORITHM ‘ZLIB’;

old RMAN configuration parameters:
CONFIGURE COMPRESSION ALGORITHM ‘BZIP2’;
new RMAN configuration parameters:
CONFIGURE COMPRESSION ALGORITHM ‘ZLIB’;
new RMAN configuration parameters are successfully stored

RMAN> backup as compressed backupset database plus archivelog;
…略

3.2更改压缩算法设置（11gR2版本）

RMAN> CONFIGURE COMPRESSION ALGORITHM ‘MEDIUM’;

new RMAN configuration parameters:
CONFIGURE COMPRESSION ALGORITHM ‘MEDIUM’ AS OF RELEASE ‘DEFAULT’ OPTIMIZE FOR LOAD TRUE;
new RMAN configuration parameters are successfully stored

4.定义归档日志（Archived log）删除策略

在11g之前，只有备份集的保存策略，归档日志需要使用delete命令来删除，在11g中可以使用configure命令
来设置oralce的归档保留删除策略。日志删除策略适用于所有日志归档的目的地，包括参数指定的路径，和
闪回区域。另外，除非手工强制删除归档日志，否则归档日志的保留策略遵守定义的归档日志删除策略。

4.1rman的删除策略有4中情况值

4.11：TO APPLIED ON  [ALL] STANDBY
指定归档日志被（所有）备库应用之后才能删除

4.12：TO SHIPPED TO  [ALL] STANDBY
指定归档日志被传送到（所有）备库之后才删除

4.13：NONE
指定归档日志删除策略为空

4.14：BACKED UP integer  TIMES TO DEVICE   TYPE deviceSpecifier
指定归档日志备份到指定设备类型的对应次数之后才删除

测试如下：

4.2默认的策略是none

RMAN> show all;

···略
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default

4.3设置删除策略

RMAN> configure archivelog deletion policy to APPLIED ON STANDBY;

new RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON STANDBY;
new RMAN configuration parameters are successfully stored

RMAN> configure archivelog deletion policy to SHIPPED TO STANDBY;

old RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON STANDBY;
new RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO SHIPPED TO STANDBY;
new RMAN configuration parameters are successfully stored

RMAN> configure archivelog deletion policy to backed up 2 times to device type disk;

old RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO SHIPPED TO STANDBY;
new RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 2 TIMES TO DISK;
new RMAN configuration parameters are successfully stored

RMAN> configure archivelog deletion policy to none;

old RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO BACKED UP 2 TIMES TO DISK;
new RMAN configuration parameters:
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE;
new RMAN configuration parameters are successfully stored

5.Archived Redo Log Failover

归档重做日志故障转移特性允许RMAN完成备份即使一些归档日志在目的目录是丢失或日志出现损坏情况。如果至少
有一个日志对应于系统固定的日志序列和线程号，那么就可以从闪回区或其他归档的目的地备份完好的日志。这种
特性仅支持使用多路径归档的情况下。

6.Active database duplication
11g Rman快速克隆数据库新特性 参考完整的实验介绍~（另外链接）

OCM考试相关 Oracle | Guang Cai Li | |   11grman rman new features

2 thoughts on “Oracle 11g OCM之Rman 新特性”

  1. Pingback: Ludatou's life » Oracle 11g OCM复习项目列表（更新中）

    • luda says:

      哈哈

Comments are closed.