第七章:RMAN
1、rman的定义和功能:
1) Recovery Manager
2)通过oracle 提供的包,建立备份和恢复的server process,在oracle server 上做备份和恢复
3)rman 备份 database、tablespace、datafile、controlfile、spfile、archivelog
4)支持归档和非归档
5)在归档模式下支持一致性备份(冷备份)和非一致性备份(热备份)
6)非归档只支持一致性备份
2、rman的优点:
1)只备份数据文件中已经使用过的block(备份segment高水位线以下的block),节省空间
2)备份时自动检查数据文件是否有坏块,并可以标记坏块,跳过坏块
3)可以实现增量备份
4)备份和恢复都是用rman的命令来完成
3、rman的架构:
1)target database:需要做备份的生产库
2)存储设备:disk 、tape (sbt 磁带机)存放备份文件的设备
3)channel :目标库和存储设备之间备份通道(服务进程)默认最少启动一个channel,可同时启动多个channel ,并发操作,加快备份和恢复的速度
4)server process:用于备份和恢复
5)rman备份的元数据:记录备份的信息(一般放在目标库的controlfile 里)
6)catalog database :集中管理、存放备份的元数据,还可以存储备份脚本
7} MML:media manage layer 介质管理层:用于管理磁带机的库文件或驱动
4、rman 链接目标库
1) $ORACLE_SID 和目标库一致
[oracle@work ~]$ env |grep SID
ORACLE_SID=prod
[oracle@work ~]$ rman target /
Recovery Manager: Release 10.2.0.1.0 - Production on Thu Aug 18 05:06:08 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved.
connected to target database: PROD (DBID=170319990)
RMAN>
[oracle@work ~]$ rman
Recovery Manager: Release 10.2.0.1.0 - Production on Thu Aug 18 05:10:11 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved.
RMAN> connect target /
connected to target database: PROD (DBID=170319990)
RMAN>
2)远程连接
1)在target database 启动listeners ,在client配置tnsnames
C:\Documents and Settings\liqx>rman target sys/oracle@prod
恢复管理器: Release 10.2.0.1.0 - Production on 星期四 8月 18 09:51:24 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved.
连接到目标数据库: PROD (DBID=170319990)
RMAN>
5、查看rman的默认配置,修改rman的配置信息
1)查看rman的默认配置
RMAN> show all;
using target database control file instead of recovery catalog
RMAN configuration parameters are:
CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default
CONFIGURE BACKUP OPTIMIZATION OFF; # default
CONFIGURE DEFAULT DEVICE TYPE TO DISK; # default
CONFIGURE CONTROLFILE AUTOBACKUP OFF; # default
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '%F'; # default
CONFIGURE DEVICE TYPE DISK PARALLELISM 1 BACKUP TYPE TO BACKUPSET; # default
CONFIGURE DATAFILE BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE ARCHIVELOG BACKUP COPIES FOR DEVICE TYPE DISK TO 1; # default
CONFIGURE MAXSETSIZE TO UNLIMITED; # default
CONFIGURE ENCRYPTION FOR DATABASE OFF; # default
CONFIGURE ENCRYPTION ALGORITHM 'AES128'; # default
CONFIGURE ARCHIVELOG DELETION POLICY TO NONE; # default
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '/u01/app/oracle/product/10.2.0/db_1/dbs/snapcf_prod.f'; # default
RMAN> CONFIGURE CONTROLFILE AUTOBACKUP on;
new RMAN configuration parameters:
CONFIGURE CONTROLFILE AUTOBACKUP ON;
new RMAN configuration parameters are successfully stored
------off:默认情况下,在备份system 表空间时,会备份控制文件和spfile
on: 在做任何文件的备份时,会自动备份控制文件和spfile,并且数据库的物理结构发生变化时,也自动备份controlfile。
2)format 指明备份文件的路径和文件名
RMAN备份文件格式
备份文件可以自定义各种各样的格式,如下:
%c 备份片的拷贝数
%D 位于该月中的第几天 (DD)
%M 位于该年中的第几月 (MM)
%F 一个基于DBID 唯一的名称,这个格式的形式为c-IIIIIIIIII-YYYYMMDD-QQ,
%d 数据库名称其中IIIIIIIIII 为该数据库的DBID,YYYYMMDD 为日期,QQ 是一个1-256 的序列
%n 数据库名称,向右填补到最大八个字符
%u 一个八个字符的名称代表备份集与创建时间
%p 该备份集中的备份片号,从1 开始到创建的文件数
%U 一个唯一的文件名,代表%u_%p_%c
%s 备份集的号
%t 备份集时间戳
%T 年月日格式(YYYYMMDD)
6、rman备份的分类:
1)backupset:只备份datafile里已经使用过的块(HWM以下)、可以实现增量备份(可以备份到disk和tape)。如果只启用一个channel,默认会把所有备份的datafile放入到一个backupset里
,并且生成一个备份片(backup piece,在OS下看到的备份文件)
2)backup piece :由backupset 生成的备份文件,保存在os下
3) copy(snapshot 镜像):实际上和手工cp 是类似的,备份datafile 所有的数据块,不能实现增量备份(但可以作为增量备份的0级备份),只能备份到disk ,不能备份到tape,
恢复时速度快
6、rman的命令格式:
1)交互式
RMAN> shutdown immediate;
database closed
database dismounted
Oracle instance shut down
RMAN> startup force mount;
Oracle instance started
database mounted
Total System Global Area 314572800 bytes
Fixed Size 1219184 bytes
Variable Size 67110288 bytes
Database Buffers 243269632 bytes
Redo Buffers 2973696 bytes
RMAN> alter database open;
database opened
RMAN> sql 'alter system switch logfile';
sql statement: alter system switch logfile
RMAN> sql 'select * from scott.emp';
sql statement: select * from scott.emp
---------对select 不显示结果
RMAN> backup datafile 2 format '/disk1/rman/prod/%d_%s_%t.bak';
Starting backup at 18-AUG-11
allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=139 devtype=DISK
channel ORA_DISK_1: starting full datafile backupset
channel ORA_DISK_1: specifying datafile(s) in backupset
input datafile fno=00002 name=/u01/app/oracle/oradata/prod/users01.dbf
channel ORA_DISK_1: starting piece 1 at 18-AUG-11
channel ORA_DISK_1: finished piece 1 at 18-AUG-11
piece handle=/disk1/rman/prod/PROD_2_759476271.bak tag=TAG20110818T053751 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:03
Finished backup at 18-AUG-11
RMAN> list backup;
List of Backup Sets
===================
BS Key Type LV Size Device Type Elapsed Time Completion Time
------- ---- -- ---------- ----------- ------------ ---------------
1 Full 464.00K DISK 00:00:03 18-AUG-11
BP Key: 1 Status: AVAILABLE Compressed: NO Tag: TAG20110818T053751
Piece Name: /disk1/rman/prod/PROD_2_759476271.bak
List of Datafiles in backup set 1
File LV Type Ckp SCN Ckp Time Name
---- -- ---- ---------- --------- ----
2 Full 1316126 18-AUG-11 /u01/app/oracle/oradata/prod/users01.dbf
-----备份片的大小为464k ,只包含已经使用的block
RMAN>
2)批处理
RMAN> run {
2> shutdown immediate;
3> startup mount;
4> allocate channel c1 type disk;
5> allocate channel c2 type disk;
6> backup database format '/disk1/rman/prod/%d_%s.bak';
7> alter database open;
8> }