仅记录一次Oracle 11g rac安装过程.本文出自:http://koumm.blog.51cto.com/
1. 采用RHEL6.5 multipath多路径软件安装采用udev方式配置ASM共享磁盘不成功，当时因为时间关系没有过多的分析与尝试。
OEL6.X IBM v3500存储多路径配置
http://koumm.blog.51cto.com/703525/1439760
2. 采用RHEL6.5 multipath多路径软件安装采用ASMLIB方式配置ASM共享磁盘成功，但是在第二节点执 行root.sh报如下错误提示，解决方式见3.
Disk Group CRS creation failed with the following message:
ORA-15018: diskgroup cannot be created
ORA-15072: command requires at least 1 regular failure groups, discovered only 0
ORA-15080: synchronous I/O operation to a disk failed
Configuration of ASM ... failed
see asmca logs at /u01/app/grid/cfgtoollogs/asmca for details
Did not succssfully configure and start ASM at /u01/app/11.2.0/grid/crs/install/crsconfig_lib.pm line 6912.
/u01/app/11.2.0/grid/perl/bin/perl -I/u01/app/11.2.0/grid/perl/lib - I/u01/app/11.2.0/grid/crs/install /u01/app/11.2.0/grid/crs/install/rootcrs.pl execution failed
3. 解决方式如下
node1,node2 下：
# vi /etc/sysconfig/oracleasm
ORACLEASM_ENABLED=true
ORACLEASM_UID=grid
ORACLEASM_GID=asmdba
ORACLEASM_SCANBOOT=true
ORACLEASM_SCANORDER="dm"
ORACLEASM_SCANEXCLUDE="sd"
ORACLEASM_USE_LOGICAL_BLOCK_SIZE=false
# /etc/init.d/oracleasm restart
第二节点先执行清除配置，再执行root.sh即可:
# /u01/app/11.2.0/grid/crs/install/roothas.pl -delete -force -verbose
# /u01/app/11.2.0/grid/root.sh
