Linux下创建RAID 10
创建RAID10，最少需要4个磁盘
[root@kashu ~]# fdisk -l /dev/sdb
Device Boot Start End Blocks Id System
/dev/sdb1 1 65 522081 83 Linux
/dev/sdb2 66 130 522112+ 83 Linux
/dev/sdb3 131 195 522112+ 83 Linux
/dev/sdb4 196 2610 19398487+ 5 Extended
/dev/sdb5 196 260 522081 83 Linux
1、先创建两个RAID 1：
[root@kashu ~]# mdadm -C /dev/md0 -l1 -n2 /dev/sdb[1-2]
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
[root@kashu ~]# mdadm -C /dev/md1 -l1 -n2 /dev/sdb{3,5}
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md1 started.
检查一下，OK
[root@kashu ~]# cat /proc/mdstat
Personalities : [raid0] [raid1] [raid6] [raid5] [raid4]
md1 : active raid1 sdb5[1] sdb3[0]
522069 blocks super 1.2 [2/2] [UU]
md0 : active raid1 sdb2[1] sdb1[0]
522069 blocks super 1.2 [2/2] [UU]
unused devices: <none>
2、再创建一个RAID 0：
[root@kashu ~]# mdadm -C /dev/md10 -l0 -n2 /dev/md[0-1]
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md10 started.
检查一下，OK
[root@kashu ~]# mdadm -D /dev/md*
mdadm: /dev/md does not appear to be an md device
/dev/md0:
Version : 1.2
Creation Time : Thu May 2 03:06:16 2013
Raid Level : raid1
Array Size : 522069 (509.92 MiB 534.60 MB)
Used Dev Size : 522069 (509.92 MiB 534.60 MB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Update Time : Thu May 2 03:09:43 2013
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Name : kashu.localdomain:0 (local to host kashu.localdomain)
UUID : eea41616:85b7da19:652e8088:696cd948
Events : 17
Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 18 1 active sync /dev/sdb2
/dev/md1:
Version : 1.2
Creation Time : Thu May 2 03:06:41 2013
Raid Level : raid1
Array Size : 522069 (509.92 MiB 534.60 MB)
Used Dev Size : 522069 (509.92 MiB 534.60 MB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Update Time : Thu May 2 03:09:43 2013
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Name : kashu.localdomain:1 (local to host kashu.localdomain)
UUID : 9ee855c7:9fc9c27e:67f1fb01:a2430406
Events : 17
Number Major Minor RaidDevice State
0 8 19 0 active sync /dev/sdb3
1 8 21 1 active sync /dev/sdb5
/dev/md10:
Version : 1.2
Creation Time : Thu May 2 03:09:43 2013
Raid Level : raid0
Array Size : 1041408 (1017.17 MiB 1066.40 MB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Update Time : Thu May 2 03:09:43 2013
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Chunk Size : 512K
Name : kashu.localdomain:10 (local to host kashu.localdomain)
UUID : de8aaea0:b405c41b:c2390d75:91051b0b
Events : 0
Number Major Minor RaidDevice State
0 9 0 0 active sync /dev/md0
1 9 1 1 active sync /dev/md1
3、新建文件系统
[root@kashu ~]# mkfs.ext4 /dev/md10
mke2fs 1.41.12 (17-May-2010)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=128 blocks, Stripe width=256 blocks
65152 inodes, 260352 blocks
13017 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=268435456
8 block groups
32768 blocks per group, 32768 fragments per group
8144 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376
Writing inode tables: done
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 31 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
4、创建挂载点，并挂载使用
[root@kashu ~]# mkdir /mnt/raid10
[root@kashu ~]# mount /dev/md10 /mnt/raid10
[root@kashu ~]# ll /mnt/raid10
total 16
drwx------ 2 root root 16384 May 2 03:11 lost+found
[root@kashu ~]#
df -hT /dev/md10
Filesystem Type Size Used Avail Use% Mounted on
/dev/md10 ext4 1001M 39M 912M 5% /mnt/raid10
5、添加挂载信息到/etc/fstab文件中
[root@kashu ~]# blkid /dev/md10
/dev/md10: UUID="f82eefa3-28f3-4dda-8873-63e29f4d9abf" TYPE="ext4"
[root@kashu ~]# vim /etc/fstab
UUID="f82eefa3-28f3-4dda-8873-63e29f4d9abf"/mnt/raid10ext4defaults00
6、把RAID阵列相关信息添加到/etc/mdadm.conf文件中，注意，这里写入了3条RAID阵列信息
[root@kashu ~]# mdadm -Ds >> /etc/mdadm.conf
ARRAY /dev/md0 metadata=1.2 name=kashu.localdomain:0 UUID=eea41616:85b7da19:652e8088:696cd948
ARRAY /dev/md1 metadata=1.2 name=kashu.localdomain:1 UUID=9ee855c7:9fc9c27e:67f1fb01:a2430406
ARRAY /dev/md10 metadata=1.2 name=kashu.localdomain:10 UUID=de8aaea0:b405c41b:c2390d75:91051b0b
如何删除RAID 10呢？注意，删除的时候要注意删除的顺序，是自上而下删除。换一种说法，删除时是反着创建时的顺序来的。
1）先把挂载点卸载
[root@kashu ~]#
umount /mnt/raid10
2）再把RAID 0删除
[root@kashu ~]#
mdadm -S /dev/md10
mdadm: stopped /dev/md10
3）删除RAID阵列中md0和md1这两个成员组的超级块信息（这个容易忘记删除，注意！）
[root@kashu ~]#
mdadm --zero-superblock /dev/md[0-1]
4）再把RAID 1删除
[root@kashu ~]#
mdadm -S /dev/md[0-1]
mdadm: stopped /dev/md0
mdadm: stopped /dev/md1
5）删除RAID阵列中各个成员磁盘的超级块信息
[root@kashu ~]#
mdadm --zero-superblock /dev/sdb[1-3,5]
6）删除/etc/fstab中的对应的挂载信息
7）删除/etc/mdadm.conf中对应的RAID阵列信息