RMAN备份对于Oracle数据库的备份与恢复简单易用，成本低廉。对于使用非catalog方式而言，将RMAN脚本嵌入到shell脚本，然后再通过crontab来实现中小型数据库数据库备份无疑是首选。本文提供了一个简单易用的基于linux shell下的RMAN备份脚本供参考。大家可根据自己的需要进行适当调整。
RMAN备份相关方面的知识较多，可以参考：
RMAN 概述及其体系结构
RMAN 配置、监控与管理
RMAN 备份详解
RMAN 还原与恢复
RMAN catalog 的创建和使用
基于catalog 创建RMAN存储脚本
基于catalog 的RMAN 备份与恢复
RMAN 备份路径困惑
其次是对于shell脚本中调用sql,rman语句可以参考
Linux/Unix shell 脚本中调用SQL,RMAN脚本
Linux/Unix shell sql 之间传递变量
下面是脚本的具体内容
##===========================================================
## db_bak_rman.sh
## created by Robinson
## 2011/11/07
## usage: db_bak_rman.sh <$ORACLE_SID> <$BACKUP_LEVEL>
## BACKUP_LEVEL:
## F: full backup
## 0: level 0
## 1: level 1
##============================================================
#!/bin/bash
# User specific environment and startup programs
if [ -f ~/.bash_profile ];
then
. ~/.bash_profile
fi
ORACLE_SID=${1}; export ORACLE_SID
RMAN_LEVEL=${2}; export RMAN_LEVEL
TIMESTAMP=`date +%Y%m%d%H%M`; export TIMESTAMP
DATE=`date +%Y%m%d`; export DATE
RMAN_DIR=/u02/database/${ORACLE_SID}/backup/rman; export RMAN_DIR
RMAN_DATA=${RMAN_DIR}/${DATE}; export RMAN_DATA
#RMAN_LOG=$RMAN_DATA/log; export RMAN_LOG
RMAN_LOG=/u02/database/${ORACLE_SID}/backup/rman/log export RMAN_LOG
# Check rman level
#======================================================================
if [ "$RMAN_LEVEL" == "F" ];
then unset INCR_LVL
BACKUP_TYPE=full
else
INCR_LVL="INCREMENTAL LEVEL ${RMAN_LEVEL}"
BACKUP_TYPE=lev${RMAN_LEVEL}
fi
RMAN_FILE=${RMAN_DATA}/${ORACLE_SID}_${BACKUP_TYPE}_${TIMESTAMP}; export RMAN_FILE
SSH_LOG=${RMAN_LOG}/${ORACLE_SID}_${BACKUP_TYPE}_${TIMESTAMP}.log; export SSH_LOG
MAXPIECESIZE=4G; export MAXPIECESIZE
#Check RMAN Backup Path
#=========================================================================
if ! test -d ${RMAN_DATA}
then
mkdir -p ${RMAN_DATA}
fi
echo "---------------------------------" >>${SSH_LOG}
echo " " >>${SSH_LOG}
echo "Rman Begin to Working ........." >>${SSH_LOG}
echo "Begin time at:" `date` --`date +%Y%m%d%H%M` >>${SSH_LOG}
#Startup rman to backup
#=============================================================================
$ORACLE_HOME/bin/rman log=${RMAN_FILE}.log <<EOF
connect target /
run {
CONFIGURE RETENTION POLICY TO RECOVERY WINDOW OF 3 DAYS;
CONFIGURE BACKUP OPTIMIZATION ON;
CONFIGURE CONTROLFILE AUTOBACKUP ON;
CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO '${RMAN_FILE}_%F';
ALLOCATE CHANNEL 'ch1' TYPE DISK maxpiecesize=${MAXPIECESIZE};
ALLOCATE CHANNEL 'ch2' TYPE DISK maxpiecesize=${MAXPIECESIZE};
set limit channel ch1 readrate=10240;
set limit channel ch1 kbytes=4096000;
set limit channel ch2 readrate=10240;
set limit channel ch2 kbytes=4096000;
CROSSCHECK ARCHIVELOG ALL;
DELETE NOPROMPT EXPIRED ARCHIVELOG ALL;
BACKUP
#AS COMPRESSED BACKUPSET
${INCR_LVL}
DATABASE FORMAT '${RMAN_FILE}_%U' TAG '${ORACLE_SID}_${BACKUP_TYPE}_${TIMESTAMP}';
SQL 'ALTER SYSTEM ARCHIVE LOG CURRENT';
BACKUP ARCHIVELOG ALL FORMAT '${RMAN_FILE}_arc_%U' TAG '${ORACLE_SID}_arc_${TIMESTAMP}'
DELETE INPUT;
DELETE NOPROMPT OBSOLETE;
RELEASE CHANNEL ch1;
RELEASE CHANNEL ch2;
}
sql "alter database backup controlfile to ''${RMAN_DATA}/cntl_${BACKUP_TYPE}.bak''";
exit;
EOF
RC=$?
cat ${RMAN_FILE}.log >>${SSH_LOG}
echo "Rman Stop working @ time:"`date` `date +%Y%m%d%H%M` >>${SSH_LOG}
echo >>${SSH_LOG}
echo "------------------------" >>${SSH_LOG}
echo "------ Disk Space ------" >>${SSH_LOG}
df -h >>${SSH_LOG}
echo >>${SSH_LOG}
if [ $RC -ne "0" ]; then
echo "------ error ------" >>${SSH_LOG}
else
echo "------ no error found during RMAN backup peroid------" >>${SSH_LOG}
rm -rf ${RMAN_FILE}.log
fi
#Remove old backup than 3 days
#============================================================================
RMDIR=${RMAN_DIR}/`/bin/date +%Y%m%d -d "3 days ago"`; export RMDIR
echo >>${SSH_LOG}
echo -e "------Remove old backup than 3 days ------\n" >>${SSH_LOG}
if test -d ${RMDIR}
then
rm -rf ${RMDIR}
RC=$?
fi
echo >>${SSH_LOG}
if [ $RC -ne "0" ]; then
echo -e "------ Remove old backup exception------ \n" >>${SSH_LOG}
else
echo -e "------ no error found during remove old backup set peroid------ \n" >>${SSH_LOG}
fi
exit
oracle@SZDB:~/robinson/scripts/dba_scripts/custom/sql> ./db_bak_rman.sh GOBO1 0
RMAN> RMAN> 2> 3> 4> 5> 6> 7> 8> 9> 10> 11> 12> 13> 14> 15>
16> 17> 18> 19> 20> 21> 22> 23> 24> RMAN> RMAN>
oracle@SZDB:~/robinson/scripts/dba_scripts/custom/sql>
oracle@SZDB:/u02/database/GOBO1/backup/rman> ls
20120928 log
oracle@SZDB:/u02/database/GOBO1/backup/rman/20120928> ls
cntl_lev0.bak GOBO1_lev0_201209281421_arc_4onmb9ro_1_1
GOBO1_lev0_201209281421_4knmb9jn_1_1 GOBO1_lev0_201209281421_c-733951103-20120928-00
GOBO1_lev0_201209281421_4lnmb9jn_1_1 GOBO1_lev0_201209281421_c-733951103-20120928-01
GOBO1_lev0_201209281421_arc_4nnmb9rn_1_1
更多参考：
有关基于用户管理的备份和备份恢复的概念请参考
Oracle 基于用户管理恢复的处理(详细描述了介质恢复及其处理)
Oracle 基于备份控制文件的恢复(unsing backup controlfile)
有关RMAN的备份恢复与管理请参考
有关ORACLE体系结构请参考
