Multipath errors on RHEL6.4 with IBM3850 and IBM DS5100

最近帮客户装一套11.2.0.4的RAC，操作系统RHEL6.4，将安装过程中遇到的一些问题记录如下：

IBMx3850安装RHEL6.4系统，存储使用IBM DS5100，装好操作系统映射了lun后重启系统发现有报错：

[root linux1]# dmesg | tail
end_request: I/O error, dev sde, sector 0
Buffer I/O error on device sde, logical block 0
sd 2:0:1:0: Device not ready: <6>: Current: sense key: Not Ready
  Additional sense: Logical unit not ready, manual intervention required
end_request: I/O error, dev sde, sector 209715192
Buffer I/O error on device sde, logical block 26214399
sd 2:0:1:0: Device not ready: <6>: Current: sense key: Not Ready
  Additional sense: Logical unit not ready, manual intervention required
end_request: I/O error, dev sde, sector 0

Buffer I/O error on device sde, logical block 0

pvscan也有报错

#pvscan
/dev/sdc: read failed after 0 of 4096 at 0: Input/output error
/dev/sdc: read failed after 0 of 4096 at 1462779183104: Input/output error
/dev/sdc: read failed after 0 of 4096 at 1462779240448: Input/output error
/dev/sdc: read failed after 0 of 4096 at 4096: Input/output error

multipath均已做配置，何来报错？ google了一下，原来multipath并不支持这个存储，只能使用IBM的多路径软件RDAC。安装后重启无报错。

安装过程见：

http://xu3jin.blog.51cto.com/2261216/1311174