1、安装（CentOS6.7默认已经安装）
find ./ -name “-mapper-”

rpm -ivh device-mapper-libs-1.02.95-2.el6.x86_64.rpm device-mapper-event-1.02.95-2.el6.x86_64.rpm device-mapper-multipath-libs-0.4.9-87.el6.x86_64.rpm device-mapper-event-libs-1.02.95-2.el6.x86_64.rpm device-mapper-1.02.95-2.el6.x86_64.rpm device-mapper-multipath-0.4.9-87.el6.x86_64.rpm device-mapper-persistent-data-0.3.2-1.el6.x86_64.rpm

rpm -qa | grep device-mapper

2、内核加载
lsmod | grep -i multi
显示如下
dm_multipath 17916 2 dm_round_robin
dm_mod 99200 8 dm_multipath,dm_mirror,dm_log

如果不显示可以尝试手动加载
modprobe dm-multipath
modprobe dm-round-robin

3、启动
service multipathd restart
chkconfig –level 2345 multipathd on

4、生成multipath.conf
默认在路径为/etc/multipath.conf

mpathconf --enable --find_multipaths y --with_module y --with_chkconfig y 

mpathconf默认路径在/sbin下

5、查看
一般情况下（我在CentOS6.7平台测试）至此已经可以使用，使用一下命令观察
1） more /etc/multipath/wwids

# Multipath wwids, Version : 1.0
# NOTE: This file is automatically maintained by multipath and multipathd.
# You should not need to edit this file in normal circumstances.
#
# Valid WWIDs:
/360002ac0000000000000004f000044b8/

2）multipath -ll
多路径信息mpathb为多路径的实际操作逻辑路径
mpathb (360002ac0000000000000004f000044b8) dm-0 3PARdata,VV
size=1.0T features=’0’ hwhandler=’0’ wp=rw
-+- policy=’round-robin 0’ prio=1 status=active
|- 6:0:0:0 sdb 8:16 active ready running
|- 5:0:0:0 sdd 8:48 active ready running
|- 6:0:1:0 sdc 8:32 active ready running
- 5:0:1:0 sde 8:64 active ready running

3）补充—查看scsi相关的wwid
示例：scsi_id -g /dev/sdb

6、附加内容：multipath.conf配置，在测试过程中发现
CentOS6.7桌面版安装后配置文件信息示例如下，同时可
自动将多条路径归并，只显示一条归并后的逻辑路径
/dev/mapper/mpathb。

# multipath.conf written by anaconda

defaults {
        user_friendly_names yes
}
blacklist {
        devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
        devnode "^hd[a-z]"
        devnode "^dcssblk[0-9]*"
        device {
                vendor "DGC"
                product "LUNZ"
        }
        device {
                vendor "IBM"
                product "S/390.*"
        }
        # don't count normal SATA devices as multipaths
        device {
                vendor  "ATA"
        }
        # don't count 3ware devices as multipaths
        device {
                vendor  "3ware"
        }
        device {
                vendor  "AMCC"
        }
        # nor highpoint devices
        device {
                vendor  "HPT"
        }
        wwid "3600508b1001caa4676df795bb828e968"
        device {
                vendor KVM
                product vmDisk-CD
        }
        device {
                vendor HP
                product Virtual_DVD-ROM
        }
        wwid "*"
}
blacklist_exceptions {
        wwid "360002ac0000000000000004f000044b8"
}
multipaths {
        multipath {
                uid 0
                gid 0
                wwid "360002ac0000000000000004f000044b8"
                mode 0600
        }
}