问题：
我的rac环境不小心通过chown命令改变了/u01目录及其子目录的权限，导致rac节点2数据库宕掉，sqlplus下打开数据库报错如下：
[oracle@node2 ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.4.0 Production on Fri Mar 25 19:53:58 2016
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup
ORA-01078: failure in processing system parameters
ORA-01565: error in identifying file '+DATA/orcl/spfileorcl.ora'
ORA-17503: ksfdopn:2 Failed to open file +DATA/orcl/spfileorcl.ora
ORA-12547: TNS:lost contact
解决方法：
1、查看grid用户下/u01/app/11.2.0/grid/bin/oracle文件权限变为-rwxr-x--x，其正常权限应为-rwsr-s--x（6751）。
[oracle@node2 dbs]$ su - grid
Password:
[grid@node2 ~]$ cd /u01/app/11.2.0/grid/bin/
[grid@node2 bin]$ ll oracle
-rwxr-x--x 1 grid oinstall 209914869 Mar 21 18:02 oracle
2、修改/u01/app/11.2.0/grid/bin/oracle文件夹权限
[grid@node2 bin]$ chmod 6751 oracle
[grid@node2 bin]$ ll oracle
-rwsr-s--x 1 grid oinstall 209914869 Mar 21 18:02 oracle
3、查看/u01/app/oracle/product/11.2.0/db_1/bin/oracle目录权限，没有问题
[oracle@node2 ~]$ ll /u01/app/oracle/product/11.2.0/db_1/bin/oracle
-rwsr-s--x 1 oracle asmadmin 239627031 Mar 22 09:27 /u01/app/oracle/product/11.2.0/db_1/bin/oracle
4、重启数据库
SQL> startup
ORACLE instance started.
Total System Global Area 2505338880 bytes
Fixed Size 2255832 bytes
Variable Size 805307432 bytes
Database Buffers 1677721600 bytes
Redo Buffers 20054016 bytes
Database mounted.
Database opened.
5、查看node1节点/u01/app/11.2.0/grid/bin/oracle文件权限
[grid@node1 bin]$ pwd
/u01/app/11.2.0/grid/bin
[grid@node1 bin]$ ll oracle
-rwxr-x--x 1 grid oinstall 209914869 Mar 21 18:01 oracle
[grid@node1 bin]$ chmod 6751 oracle
[grid@node1 bin]$ ll oracle
-rwsr-s--x 1 grid oinstall 209914869 Mar 21 18:01 oracle
6、查看/u01/app/oracle/product/11.2.0/db_1/bin/oracle
[oracle@node1 bin]$ pwd
/u01/app/oracle/product/11.2.0/db_1/bin
[oracle@node1 bin]$ ll oracle
-rwsr-s--x 1 oracle asmadmin 239627031 Mar 22 09:24 oracle
7、查看crs资源
[grid@node2 ~]$ crsctl status resource -t
--------------------------------------------------------------------------------
NAME TARGET STATE SERVER STATE_DETAILS
--------------------------------------------------------------------------------
Local Resources
--------------------------------------------------------------------------------
ora.DATA.dg
ONLINE ONLINE node1
ONLINE ONLINE node2
ora.FLASH.dg
ONLINE ONLINE node1
ONLINE ONLINE node2
ora.GRIDDG.dg
ONLINE ONLINE node1
ONLINE ONLINE node2
ora.LISTENER.lsnr
ONLINE ONLINE node1
ONLINE ONLINE node2
ora.asm
ONLINE ONLINE node1 Started
ONLINE ONLINE node2 Started
ora.gsd
OFFLINE OFFLINE node1
OFFLINE OFFLINE node2
ora.net1.network
ONLINE ONLINE node1
ONLINE ONLINE node2
ora.ons
ONLINE ONLINE node1
ONLINE ONLINE node2
ora.registry.acfs
ONLINE ONLINE node1
ONLINE ONLINE node2
--------------------------------------------------------------------------------
Cluster Resources
--------------------------------------------------------------------------------
ora.LISTENER_SCAN1.lsnr
1 ONLINE ONLINE node1
ora.cvu
1 ONLINE ONLINE node1
ora.node1.vip
1 ONLINE ONLINE node1
ora.node2.vip
1 ONLINE ONLINE node2
ora.oc4j
1 ONLINE ONLINE node1
ora.orcl.db
1 ONLINE ONLINE node1 Open
2 ONLINE ONLINE node2 Open
ora.scan1.vip
1 ONLINE ONLINE node1
参考：
http://www.lunar2013.com/2014/10/11-2-rac-%E4%BF%AE%E6%94%B9%E4%BA%86%E7%9B%AE%E5%BD%95%E6%9D%83%E9%99%90u01%E5%90%8Ecrs%E4%B8%8D%E8%83%BD%E5%90%AF%E5%8A%A8%E7%9A%84%E8%A7%A3%E5%86%B3%E6%96%B9%E6%B3%95-1-%E6%89%8B%E5%B7%A5%E4%BF%AE-2.html