Oracle11gR2 RAC安装Clusterware结束，在第二个节点执行root.sh脚本的是报如下错误：
DiskGroup DATA1 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
在Oracle的官网搜了一下，相关解释如下
Applies to:
Oracle Server - Enterprise Edition - Version: 11.2.0.1 and later[Release: 11.2 and later ]
Information in this document applies to any platform.
Symptoms
While installing Oracle Grid Infrastructure with ASM, root.sh ran successfully in first node, but fails on the second node.
Error example
1. root.sh failed on second node with following errors
-------------------------------------------------------
DiskGroup DATA1 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
Configuration of ASM failed, see logs for details
2. rootcrs_nodename.log
-----------------------
-02-03 13:40:43: Configuring ASM via ASMCA
-02-03 13:40:43: Executing as oracle: /u01/app/1120/grid/bin/asmca -silent -diskGroupName DATA1 -diskList ORCL:DATA1 -redundancy EXTERNAL -configureLocalASM
-02-03 13:40:43: Running as user oracle: /u01/app/1120/grid/bin/asmca -silent -diskGroupName DATA1 -diskList ORCL:DATA1 -redundancy EXTERNAL -configureLocalASM
-02-03 13:40:43: Invoking "/u01/app/1120/grid/bin/asmca -silent -diskGroupName DATA1 -diskList ORCL:DATA1 -redundancy EXTERNAL -configureLocalASM" as user "oracle"
-02-03 13:40:51: Configuration of ASM failed, see logs for details
3. On the 2nd node
/etc/oratab files shows +ASM1, rather than +ASM2
4. The following commands on the 2nd node show the ASM disk information correctly
/etc/init.d/oracleasm listdisks
/etc/init.d/oracleasm scandisks
ls -ltr /dev/oracleasm/disks
Cause
After configuring multipath disks on Linux x86-64, proper parameters have not been configured in /etc/sysconfig/oracleasm
Solution
On all nodes,
1. Modify the /etc/sysconfig/oracleasm with:
ORACLEASM_SCANORDER="dm"
ORACLEASM_SCANEXCLUDE="sd"
2. restart the asmlib by :
# /etc/init.d/oracleasm restart
3. Run root.sh on the 2nd node
在这里要注意的事，在运行root.sh脚本的时候，会报如下错误：
Using configuration parameter file: /oracle/grid/crs/install/crsconfig_params
CRS is already configured on this node for crshome=0
Cannot configure two CRS instances on the same cluster.
Please deconfigure before proceeding with the configuration of new home.
因为之前已经运行过了。我们需要把之前注册的信息删除之后，在运行root.sh脚本。执行如下命令，删除节点注册信息：
# /oracle/grid/crs/install/roothas.pl -delete -force -verbose
待删除完成后在执行，就不会报错了。
参考：
/abenz/archive//06/08/1754328.html
