部署raid10磁盘阵列至少需要4快硬盘。
linux系统中，使用mdadm命令创建和管理软件RAID磁盘阵列。
测试：使用mdadm命令创建raid10，名称为/dev/md0
1、测试
[root@linuxprobe dev]# pwd ## 查看当前路径
/dev
[root@linuxprobe dev]# find md* ## 查看md开头的文件
find: ‘md*’: No such file or directory
[root@linuxprobe dev]# find sd* ## 查看硬盘
sda
sda1
sda2
sdb
sdc
sdd
sde
[root@linuxprobe dev]# mdadm -Cv /dev/md0 -a yes -n 4 -l 10 /dev/sdb /dev/sdc /dev/sdd /dev/sde ## 创建 raid10 磁盘阵列 /dev/md0
## -C 代表创建，-v表示显示过程，-a yes 代表自动创建设备文件，-n 4 表示使用4块硬盘来部署磁盘阵列，-l 10 表示RAID10方案
mdadm: layout defaults to n2
mdadm: layout defaults to n2
mdadm: chunk size defaults to 512K
mdadm: size set to 20954624K
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
2、检测磁盘阵列
[root@linuxprobe dev]# pwd
/dev
[root@linuxprobe dev]# find md*
md0
3、将制作好的 RAID10磁盘阵列进行格式化，指定为ext4文件系统
[root@linuxprobe dev]# mkfs.ext4 /dev/md0
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=128 blocks, Stripe width=256 blocks
2621440 inodes, 10477312 blocks
523865 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2157969408
320 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
4、对格式化为ext4的磁盘阵列进行挂载
[root@linuxprobe dev]# df -h ## 查看当前硬盘挂载情况
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/rhel-root 18G 2.9G 15G 17% /
devtmpfs 985M 0 985M 0% /dev
tmpfs 994M 80K 994M 1% /dev/shm
tmpfs 994M 8.9M 986M 1% /run
tmpfs 994M 0 994M 0% /sys/fs/cgroup
/dev/sda1 497M 119M 379M 24% /boot
/dev/sr0 3.5G 3.5G 0 100% /run/media/root/RHEL-7.0 Server.x86_64
[root@linuxprobe dev]# mkdir /RAID ## 创建挂载点
[root@linuxprobe dev]# mount /dev/md0 /RAID/ ## 挂载
[root@linuxprobe dev]# df -h ## 查看硬盘挂载情况
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/rhel-root 18G 2.9G 15G 17% /
devtmpfs 985M 0 985M 0% /dev
tmpfs 994M 80K 994M 1% /dev/shm
tmpfs 994M 8.9M 986M 1% /run
tmpfs 994M 0 994M 0% /sys/fs/cgroup
/dev/sda1 497M 119M 379M 24% /boot
/dev/sr0 3.5G 3.5G 0 100% /run/media/root/RHEL-7.0 Server.x86_64
/dev/md0 40G 49M 38G 1% /RAID
5、查看/dev/md0磁盘阵列的详细信息
[root@linuxprobe /]# mdadm -D /dev/md0
/dev/md0:
Version : 1.2
Creation Time : Wed Oct 28 21:58:25 2020
Raid Level : raid10
Array Size : 41909248 (39.97 GiB 42.92 GB)
Used Dev Size : 20954624 (19.98 GiB 21.46 GB)
Raid Devices : 4
Total Devices : 4
Persistence : Superblock is persistent
Update Time : Wed Oct 28 22:28:17 2020
State : clean
Active Devices : 4
Working Devices : 4
Failed Devices : 0
Spare Devices : 0
Layout : near=2
Chunk Size : 512K
Name : linuxprobe.com:0 (local to host linuxprobe.com)
UUID : 468018e0:1f90d057:a9944b8e:ab4e3e85
Events : 17
Number Major Minor RaidDevice State
0 8 16 0 active sync /dev/sdb
1 8 32 1 active sync /dev/sdc
2 8 48 2 active sync /dev/sdd
3 8 64 3 active sync /dev/sde
6、设为开机自动挂载
[root@linuxprobe dev]# cat /etc/fstab ## 查看当前配置文件
#
# /etc/fstab
# Created by anaconda on Wed Oct 28 20:19:08 2020
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/rhel-root / xfs defaults 1 1
UUID=2f2c5a2f-df13-4b36-99c3-9edd1b976d40 /boot xfs defaults 1 2
/dev/mapper/rhel-swap swap swap defaults 0 0
[root@linuxprobe dev]# echo -e "/dev/md0\t/RAID\text4\tdefaults\t0\t0" >> /etc/fstab ## 修改配置文件，也可以使用vim编辑器
[root@linuxprobe dev]# cat /etc/fstab ## 查看修改后配置文件
#
# /etc/fstab
# Created by anaconda on Wed Oct 28 20:19:08 2020
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/rhel-root / xfs defaults 1 1
UUID=2f2c5a2f-df13-4b36-99c3-9edd1b976d40 /boot xfs defaults 1 2
/dev/mapper/rhel-swap swap swap defaults 0 0
/dev/md0 /RAID ext4 defaults 0 0