1. yum install mdadm -y

2.添加一个硬盘2G大小：划分分区并修改类型

如图所示：

Disk /dev/vdb: 2147 MB, 2147483648 bytes

16 heads, 63 sectors/track, 4161 cylinders

Units = cylinders of 1008 * 512 = 516096 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x1af5eb72

Device Boot      Start         End      Blocks   Id  System

/dev/vdb1               1        4161     2097112+   5  Extended

/dev/vdb5               1         407      205065   fd  Linux raid autodetect

/dev/vdb6             408         814      205096+  fd  Linux raid autodetect

/dev/vdb7             815        1221      205096+  fd  Linux raid autodetect

/dev/vdb8            1222        1628      205096+  fd  Linux raid autodetect

/dev/vdb9            1629        2035      205096+  fd  Linux raid autodetect

/dev/vdb10           2036        2442      205096+  fd  Linux raid autodetect

3.使用mdadm工具建立两个raid阵列：

raid5:

mdadm -C /dev/md0 -a yes -l5 -n3 /dev/vdb{5,6,7} -x1 /dev/vdb8

其中/dev/vdb8/作为hotspare

raid1:

mdadm -C /dev/md1 -a yes -l1 -n2 /dev/vdb{9,10}

4.保存到配置文件并修改：

mdadm -D -s >>  /etc/mdadm.conf

cat /etc/mdadm.conf

# mdadm.conf written out by anaconda

MAILADDR root

AUTO +imsm +1.x -all

ARRAY /dev/md0 metadata=1.2 spares=1 name=localhost.localdomain:0 UUID=e48e7f06:d574f908:a79bfff8:fecde120 auto=yes spare-group=share

ARRAY /dev/md1 metadata=1.2 name=localhost.localdomain:1 UUID=2ffc5690:5463747a:d4927e90:717dd851 auto=yes spare-group=share

其中UUID后面时手动添加的

开启监控服务：

/etc/init.d/mdmonitor force-reload

5.验证：

raid1正常情况下，信息如下：

/dev/md1:

Version : 1.2

Creation Time : Fri Feb 17 08:31:44 2012

Raid Level : raid1

Array Size : 205084 (200.31 MiB 210.01 MB)

Used Dev Size : 205084 (200.31 MiB 210.01 MB)

Raid Devices : 2

Total Devices : 2

Persistence : Superblock is persistent

Update Time : Fri Feb 17 08:32:29 2012

State : clean

Active Devices : 2

Working Devices : 2

Failed Devices : 0

Spare Devices : 0

Name : localhost.localdomain:1  (local to host localhost.localdomain)

UUID : 2ffc5690:5463747a:d4927e90:717dd851

Events : 17

Number   Major   Minor   RaidDevice State

0     252       25        0      active sync   /dev/vdb9

1     252       26        1      active sync   /dev/vdb10

我从raid1中去除/dev/sda10

mdadm  /dev/md1 -f /dev/sdb10

再看raid1的信息：

/dev/md1:

Version : 1.2

Creation Time : Fri Feb 17 08:31:44 2012

Raid Level : raid1

Array Size : 205084 (200.31 MiB 210.01 MB)

Used Dev Size : 205084 (200.31 MiB 210.01 MB)

Raid Devices : 2

Total Devices : 3

Persistence : Superblock is persistent

Update Time : Fri Feb 17 08:42:24 2012

State : clean

Active Devices : 2

Working Devices : 2

Failed Devices : 1

Spare Devices : 0

Name : localhost.localdomain:1  (local to host localhost.localdomain)

UUID : 2ffc5690:5463747a:d4927e90:717dd851

Events : 116

Number   Major   Minor   RaidDevice State

2     252       24        0      active sync   /dev/vdb8

1     252       26        1      active sync   /dev/vdb10

0     252       25        -      faulty spare   /dev/vdb9

raid1,raid5中共享的热冗余盘/dev/vdb8自动迁移了过来，/dev/vdb9修复好后

有加为hotspare,注意的是要加在raid5中!这种迁移是单向的！