以IBM DS3512为例,讲述如何配置windows 2008的多路径 

先来看红皮书里面的一段描述:

  Resetting a controller makes the controller temporarily unavailable for I/O until the reset is complete. If a host is using logical drives owned by the controller being reset, the I/O directed to the controller is rejected. Before resetting the controller, either make sure  that the logical drives owned by the controller are not in use, or make sure that a multi-path driver is installed on all of the hosts using these logical drives. If a multipath driver is  installed, the I/Os will be processed through the alternate controller.

大体意思就是:

resetting a controller会使controller暂时无法访问IO,因此在resetting a controller之前,要确保controller拥有的那个lun不在使用火主机安装了多路径软件。如果安装了多路径软件,IO可以被另一个controller处理。否则,切换不成功。因此一定要在主机端安装MPIO软件,才能实现多路径的切换。否则虽然存储是双控,lun可以自由切换,但是如果主机不安装MPIO,也无法完成正常切换。

 

下面开始实验步骤:

拓扑图很简单:

                                    Controller A –iscsi port 10.1.1.13

windows 2008 host (10.45.45.2)----

                                    Controller B—iscsi port 10.1.1.14

 

1、首先在windows 2008 上安装MPIO

Features Summary. 选择“Add Features” ,“MPIO”

 

2、打开iscsi initiator,分别添加target端的两个IP地址

IBM DS3500 with Windows 2008 Multipathing_windows 2008

3、打开“targets”面板,选中target端的iscsi 号

IBM DS3500 with Windows 2008 Multipathing_multipath_02

4、点击“log on”

IBM DS3500 with Windows 2008 Multipathing_DS3500_03

5、点击“advanced”,本实验中源端(host)只有一个,这里先添加第一个target portal,

IBM DS3500 with Windows 2008 Multipathing_windows 2008_04

点击“ok”,退出iscsi initiator

6、现在开始配置MPIO

“开始”—“Administrative tools”—“MPIO”

IBM DS3500 with Windows 2008 Multipathing_DS3500_05

7、选中“Add support for iscsi devices”,再点击Add,接下来会要求重启系统,点击yes,重启系统

IBM DS3500 with Windows 2008 Multipathing_multipath_06

 

8、系统重启完成后,会多出一个叫做“MSFT2005IBusType 0x9”的device hardware id

IBM DS3500 with Windows 2008 Multipathing_windows 2008_07

 

9、再次打开iscsi initiator,接着在iscsi initiator中加入第二条路径,这里源端都是一样的,只有目的端的IP不一样。

IBM DS3500 with Windows 2008 Multipathing_windows 2008_08

10、查看initiator 软件的target properties,可以看到两个sessions,这就说明配置正确了

IBM DS3500 with Windows 2008 Multipathing_windows 2008_09

11、可以看到2个devices,点击“Advanced”

IBM DS3500 with Windows 2008 Multipathing_windows 2008_10

12、可以选择load balance policy,fail over或round bin等等

IBM DS3500 with Windows 2008 Multipathing_windows 2008_11

到这一步,multipath就配置完成了。下面开始测试multipath。

 

1、如下图,lun_1 目前的owner是controller B,通过iscsi将lun_1挂载到主机

 

 

IBM DS3500 with Windows 2008 Multipathing_windows 2008_12

2、现在将controller B offline,如果multipath起作用的话,那主机应该不受影响,能正常读写数据。

IBM DS3500 with Windows 2008 Multipathing_DS3500_13

 

3、此时数据仍能正常访问,说明多路径起作用了,实验成功!

IBM DS3500 with Windows 2008 Multipathing_multipath_14