如何安全卸载Oracle RAC

一个简单的脚本介绍一下如何用六步快速安全卸载Oracle RAC。

脚本分为这么几个部分：
1. stop and delete RAC instance, drop the database
2. stop and delete ASM instance
3. stop and delete listener
4. stop crs stack and clean related resource
5. clean ocr context
6. change permission and remove related ORACLE directory and Clusterware directory

其中4，5都可以直接利用Clusterware 目录install下面的脚本进行，所以这里主要介绍1，2，3，6.

1. stop and drop database

#!/bin/ksh

db=`srvctl config database`
echo “db=$db”
nl=`srvctl config database -d $db | awk ‘{print $2}’`
echo “nl=$nl”

srvctl stop database -d $db
srvctl remove database -d $db -f

for n in $nl
do
echo “stop and remove instance on instance $n”
srvctl stop instance -d $db -i $n
srvctl remove instance -d $db -i $n -f

done
echo “stop and remove database instance done”

2. stop and drop asm instance

#!/bin/ksh

nl=`olsnodes`

for n in $nl
do
srvctl stop asm -n $n
srvctl remove asm -n $n

done
echo “stop and remove asm done”

3. stop and drop listener

lsnr=`crs_stat |grep lsnr | cut -d= -f2`
for l in $lsnr
do
crs_stop $l
crs_unregister $l

done
echo “stop and remove listener done”

4. stop crs stack and clean related resource

这里需要注意的是，这里的操作必须一个节点一个节点的执行，不能并行操作，就如同安装的时候执行root.sh一样！切记切记.

on local node:
$ORA_CRS_HOME/install/rootdelete.sh local nosharedvar nosharedhome

on remote nodes:
$ORA_CRS_HOME/install/rootdelete.sh remote nosharedvar nosharedhome

5. clean ocr

only execute this on local node:
$ORA_CRS_HOME/install/rootdeinstall.sh

6. change permission and remove directory
这里之所以要更改权限是因为安装后期运行root.sh的时候会把ORA_CRS_HOME的父目录改为root权限，下次安装的时候必须修改为oracle用户

chown -Rf ractest:oinstall $ORA_CRS_HOME/../../../
rm -Rf $ORA_CRS_HOME;rm -Rf $ORACLE_BASE/../oraInventory; rm -Rf $ORACLE_BASE;rm -Rf /var/opt/oracle;rm -Rf /var/tmp/.oracle/*;rm -Rf /tmp/*;

到这里为止，下载任务就可以完成，既可以重新进行Clusterware和RAC的安装了。