作者：尹正杰
版权声明：原创作品，谢绝转载！否则将追究法律责任。
一.准备工作
1>.准备2块磁盘
假设你刚刚从别的服务器下架了2块磁盘设备(sdb和sdc)并安装到了你新买的服务器，如下图所示。
这个时候可能需要咱们手动删除磁盘上的数据，当然，你也可以只删除分区表，先在脑海里回忆一下如何操作，然后再继续往下看。
2>.删除sdb磁盘分区表
如果删除分区表后使用"lsblk"命令查看并未同步的情况，可以参考我之前的笔记，我记录了相关解决方案的笔记。
博主推荐阅读:
https://www.cnblogs.com/yinzhengjie/p/12359248.html
[root@yinzhengjie.com ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 2T 0 disk
├─sda1 8:1 0 2M 0 part
├─sda2 8:2 0 1G 0 part /boot
├─sda3 8:3 0 2T 0 part
│ ├─centos-root 253:0 0 500G 0 lvm /
│ └─centos-yinzhengjie 253:1 0 1.5T 0 lvm /yinzhengjie
└─sda4 8:4 0 1M 0 part
sdb 8:16 0 600G 0 disk
├─sdb1 8:17 0 100G 0 part
├─sdb2 8:18 0 200G 0 part
├─sdb3 8:19 0 1K 0 part
├─sdb5 8:21 0 100G 0 part
└─sdb6 8:22 0 80G 0 part
sdc 8:32 0 400G 0 disk
├─sdc1 8:33 0 100G 0 part
└─sdc2 8:34 0 200G 0 part
sdd 8:48 0 800G 0 disk
sde 8:64 0 1000G 0 disk
sr0 11:0 1 918M 0 rom
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/zero of=/dev/sdb bs=1 count=512 #只删除磁盘的分区表信息
512+0 records in
512+0 records out
512 bytes (512 B) copied, 0.00103658 s, 494 kB/s
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 2T 0 disk
├─sda1 8:1 0 2M 0 part
├─sda2 8:2 0 1G 0 part /boot
├─sda3 8:3 0 2T 0 part
│ ├─centos-root 253:0 0 500G 0 lvm /
│ └─centos-yinzhengjie 253:1 0 1.5T 0 lvm /yinzhengjie
└─sda4 8:4 0 1M 0 part
sdb 8:16 0 600G 0 disk
sdc 8:32 0 400G 0 disk
├─sdc1 8:33 0 100G 0 part
└─sdc2 8:34 0 200G 0 part
sdd 8:48 0 800G 0 disk
sde 8:64 0 1000G 0 disk
sr0 11:0 1 918M 0 rom
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/zero of=/dev/sdb bs=1 count=512 #只删除磁盘的分区表信息
3>.以同样的方式删除sdc磁盘分区表
[root@yinzhengjie.com ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 2T 0 disk
├─sda1 8:1 0 2M 0 part
├─sda2 8:2 0 1G 0 part /boot
├─sda3 8:3 0 2T 0 part
│ ├─centos-root 253:0 0 500G 0 lvm /
│ └─centos-yinzhengjie 253:1 0 1.5T 0 lvm /yinzhengjie
└─sda4 8:4 0 1M 0 part
sdb 8:16 0 600G 0 disk
sdc 8:32 0 400G 0 disk
├─sdc1 8:33 0 100G 0 part
└─sdc2 8:34 0 200G 0 part
sdd 8:48 0 800G 0 disk
sde 8:64 0 1000G 0 disk
sr0 11:0 1 918M 0 rom
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/zero of=/dev/sdc bs=1 count=512
512+0 records in
512+0 records out
512 bytes (512 B) copied, 0.00135575 s, 378 kB/s
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 2T 0 disk
├─sda1 8:1 0 2M 0 part
├─sda2 8:2 0 1G 0 part /boot
├─sda3 8:3 0 2T 0 part
│ ├─centos-root 253:0 0 500G 0 lvm /
│ └─centos-yinzhengjie 253:1 0 1.5T 0 lvm /yinzhengjie
└─sda4 8:4 0 1M 0 part
sdb 8:16 0 600G 0 disk
sdc 8:32 0 400G 0 disk
sdd 8:48 0 800G 0 disk
sde 8:64 0 1000G 0 disk
sr0 11:0 1 918M 0 rom
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 2T 0 disk
├─sda1 8:1 0 2M 0 part
├─sda2 8:2 0 1G 0 part /boot
├─sda3 8:3 0 2T 0 part
│ ├─centos-root 253:0 0 500G 0 lvm /
│ └─centos-yinzhengjie 253:1 0 1.5T 0 lvm /yinzhengjie
└─sda4 8:4 0 1M 0 part
sdb 8:16 0 600G 0 disk
sdc 8:32 0 400G 0 disk
sdd 8:48 0 800G 0 disk
sde 8:64 0 1000G 0 disk
sr0 11:0 1 918M 0 rom
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/zero of=/dev/sdc bs=1 count=512
4>.对sdb磁盘进行分区
[root@yinzhengjie.com ~]# fdisk /dev/sdb #使用"fdisk"工具对"/dev/sdb"磁盘进行分区
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0x8c3b1f6e.
Command (m for help): P
Disk /dev/sdb: 644.2 GB, 644245094400 bytes, 1258291200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x8c3b1f6e
Device Boot Start End Blocks Id System
Command (m for help): N
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): P
Partition number (1-4, default 1): 1
First sector (2048-1258291199, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-1258291199, default 1258291199): +100G
Partition 1 of type Linux and of size 100 GiB is set
Command (m for help): p #分区创建完毕后，查看一下当前的信息，注意观察Id字段，我们需要配置RAID，因此需要修改它的值。
Disk /dev/sdb: 644.2 GB, 644245094400 bytes, 1258291200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x8c3b1f6e
Device Boot Start End Blocks Id System
/dev/sdb1 2048 209717247 104857600 83 Linux
Command (m for help): t #使用"t"可以修改分区的Id，如果只有一个分区的话我们是无需选择分区的，它会自动帮咱们选择那个唯一的分区编号。
Selected partition 1
Hex code (type L to list all codes): L #使用"L"可以查看支持的Id编号
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 39 Plan 9 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 3c PartitionMagic 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 40 Venix 80286 85 Linux extended c7 Syrinx
5 Extended 41 PPC PReP Boot 86 NTFS volume set da Non-FS data
6 FAT16 42 SFS 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS/exFAT 4d QNX4.x 88 Linux plaintext de Dell Utility
8 AIX 4e QNX4.x 2nd part 8e Linux LVM df BootIt
9 AIX bootable 4f QNX4.x 3rd part 93 Amoeba e1 DOS access
a OS/2 Boot Manag 50 OnTrack DM 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 51 OnTrack DM6 Aux 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 52 CP/M a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD ee GPT
f W95 Ext'd (LBA) 54 OnTrackDM6 a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 55 EZ-Drive a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 56 Golden Bow a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 5c Priam Edisk a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 61 SpeedStor ab Darwin boot f2 DOS secondary
16 Hidden FAT16 63 GNU HURD or Sys af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 65 Novell Netware b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 75 PC/IX be Solaris boot ff BBT
1e Hidden W95 FAT1 80 Old Minix
Hex code (type L to list all codes): fd #此处我们将分区类型从83改为fd。
Changed type of partition 'Linux' to 'Linux raid autodetect'
Command (m for help): p #再次查看分区信息，注意观察"Id"列。
Disk /dev/sdb: 644.2 GB, 644245094400 bytes, 1258291200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x8c3b1f6e
Device Boot Start End Blocks Id System
/dev/sdb1 2048 209717247 104857600 fd Linux raid autodetect
Command (m for help): w #需要注意的是，上面的所有操作都是在内存中完成的，要将内存的数据真正写入磁盘，需要我们使用"w"选项哟~
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# fdisk /dev/sdb #使用"fdisk"工具对"/dev/sdb"磁盘进行分区(分配一个100G的分区空间)
[root@yinzhengjie.com ~]# fdisk -l /dev/sdb
Disk /dev/sdb: 644.2 GB, 644245094400 bytes, 1258291200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x8c3b1f6e
Device Boot Start End Blocks Id System
/dev/sdb1 2048 209717247 104857600 fd Linux raid autodetect
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# fdisk -l /dev/sdb #可以在命令行中直接查看磁盘分区表信息，无需进入到字符交互式界面
5>.对sdc磁盘进行分区
[root@yinzhengjie.com ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 2T 0 disk
├─sda1 8:1 0 2M 0 part
├─sda2 8:2 0 1G 0 part /boot
├─sda3 8:3 0 2T 0 part
│ ├─centos-root 253:0 0 500G 0 lvm /
│ └─centos-yinzhengjie 253:1 0 1.5T 0 lvm /yinzhengjie
└─sda4 8:4 0 1M 0 part
sdb 8:16 0 600G 0 disk
└─sdb1 8:17 0 100G 0 part
sdc 8:32 0 400G 0 disk
sdd 8:48 0 800G 0 disk
sde 8:64 0 1000G 0 disk
sr0 11:0 1 918M 0 rom
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/sdb of=/dev/sdc bs=1 count=512 #此处我偷懒，直接将sdb磁盘的分区表同步到sdc磁盘上啦~(这样可以免得手动去重复上面的操作来一步步手动分区。)
512+0 records in
512+0 records out
512 bytes (512 B) copied, 0.00171811 s, 298 kB/s
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 2T 0 disk
├─sda1 8:1 0 2M 0 part
├─sda2 8:2 0 1G 0 part /boot
├─sda3 8:3 0 2T 0 part
│ ├─centos-root 253:0 0 500G 0 lvm /
│ └─centos-yinzhengjie 253:1 0 1.5T 0 lvm /yinzhengjie
└─sda4 8:4 0 1M 0 part
sdb 8:16 0 600G 0 disk
└─sdb1 8:17 0 100G 0 part
sdc 8:32 0 400G 0 disk
└─sdc1 8:33 0 100G 0 part
sdd 8:48 0 800G 0 disk
sde 8:64 0 1000G 0 disk
sr0 11:0 1 918M 0 rom
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/sdb of=/dev/sdc bs=1 count=512 #此处我偷懒，直接将sdb磁盘的分区表同步到sdc磁盘上啦~(这样可以免得手动去重复上面的操作来一步步手动分区。)
[root@yinzhengjie.com ~]# fdisk -l /dev/sdc
Disk /dev/sdc: 429.5 GB, 429496729600 bytes, 838860800 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x8c3b1f6e
Device Boot Start End Blocks Id System
/dev/sdc1 2048 209717247 104857600 fd Linux raid autodetect
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# fdisk -l /dev/sdc #验证配置是否正确，我们观察sdc磁盘的Id是否是"fd"。
二.创建RAID 0块设备实战案例
1>.安装mdadm工具(用于创建RAID磁盘)
[root@yinzhengjie.com ~]# yum -y install mdadm
Loaded plugins: fastestmirror
Determining fastest mirrors
epel/x86_64/metalink | 4.5 kB 00:00:00
* base: mirrors.bfsu.edu.cn
* epel: mirrors.tuna.tsinghua.edu.cn
* extras: mirrors.huaweicloud.com
* updates: mirror.bit.edu.cn
base | 3.6 kB 00:00:00
docker-ce-stable | 3.5 kB 00:00:00
epel | 4.7 kB 00:00:00
extras | 2.9 kB 00:00:00
updates | 2.9 kB 00:00:00
(1/6): extras/7/x86_64/primary_db | 206 kB 00:00:00
(2/6): epel/x86_64/group_gz | 95 kB 00:00:00
(3/6): docker-ce-stable/x86_64/primary_db | 45 kB 00:00:00
(4/6): updates/7/x86_64/primary_db | 3.8 MB 00:00:00
(5/6): epel/x86_64/updateinfo | 1.0 MB 00:00:23
epel/x86_64/primary_db FAILED
https://download.nus.edu.sg/mirror/epel/7/x86_64/repodata/c91de4e9f4240b1b26a52668116b16495413e7f52c600294e89772ce3be7b6a8-primary.sqlite.bz2: [Errno 12] Timeout on https://download.nus.edu
.sg/mirror/epel/7/x86_64/repodata/c91de4e9f4240b1b26a52668116b16495413e7f52c600294e89772ce3be7b6a8-primary.sqlite.bz2: (28, 'Operation timed out after 30000 milliseconds with 0 out of 0 bytes received')Trying other mirror.
(6/6): epel/x86_64/primary_db | 6.9 MB 00:00:01
Resolving Dependencies
--> Running transaction check
---> Package mdadm.x86_64 0:4.1-4.el7 will be installed
--> Processing Dependency: libreport-filesystem for package: mdadm-4.1-4.el7.x86_64
--> Running transaction check
---> Package libreport-filesystem.x86_64 0:2.1.11-53.el7.centos will be installed
--> Finished Dependency Resolution
Dependencies Resolved
=============================================================================================================================================================================================
Package Arch Version Repository Size
=============================================================================================================================================================================================
Installing:
mdadm x86_64 4.1-4.el7 base 439 k
Installing for dependencies:
libreport-filesystem x86_64 2.1.11-53.el7.centos base 41 k
Transaction Summary
=============================================================================================================================================================================================
Install 1 Package (+1 Dependent package)
Total download size: 479 k
Installed size: 1.0 M
Downloading packages:
(1/2): libreport-filesystem-2.1.11-53.el7.centos.x86_64.rpm | 41 kB 00:00:00
(2/2): mdadm-4.1-4.el7.x86_64.rpm | 439 kB 00:00:00
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Total 2.4 MB/s | 479 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : libreport-filesystem-2.1.11-53.el7.centos.x86_64 1/2
Installing : mdadm-4.1-4.el7.x86_64 2/2
Verifying : mdadm-4.1-4.el7.x86_64 1/2
Verifying : libreport-filesystem-2.1.11-53.el7.centos.x86_64 2/2
Installed:
mdadm.x86_64 0:4.1-4.el7
Dependency Installed:
libreport-filesystem.x86_64 0:2.1.11-53.el7.centos
Complete!
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# yum -y install mdadm #如果是最小化安装操作需要，需要手动安装该工具
2>.使用mdadm工具创建一个RAID0的块设备
[root@yinzhengjie.com ~]# mdadm --help
mdadm is used for building, managing, and monitoring
Linux md devices (aka RAID arrays)
Usage: mdadm --create device options...
Create a new array from unused devices.
mdadm --assemble device options...
Assemble a previously created array.
mdadm --build device options...
Create or assemble an array without metadata.
mdadm --manage device options...
make changes to an existing array.
mdadm --misc options... devices
report on or modify various md related devices.
mdadm --grow options device
resize/reshape an active array
mdadm --incremental device
add/remove a device to/from an array as appropriate
mdadm --monitor options...
Monitor one or more array for significant changes.
mdadm device options...
Shorthand for --manage.
Any parameter that does not start with '-' is treated as a device name
or, for --examine-bitmap, a file name.
The first such name is often the name of an md device. Subsequent
names are often names of component devices.
For detailed help on the above major modes use --help after the mode
e.g.
mdadm --assemble --help
For general help on options use
mdadm --help-options
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# mdadm --help #查看该命令的帮助信息
[root@yinzhengjie.com ~]# lsblk /dev/sd{b,c} #注意哈，我本次试验会用到sdb和sdc这两块磁盘
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sdb 8:16 0 600G 0 disk
└─sdb1 8:17 0 100G 0 part
sdc 8:32 0 400G 0 disk
└─sdc1 8:33 0 100G 0 part
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# ll /dev/md* #目前"/dev/"目录下没有任何以"md*"开头的文件，一会执行命令后你就会发现存在啦~
ls: cannot access /dev/md*: No such file or directory
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# cat /proc/mdstat #观察md的状态
Personalities :
unused devices: <none>
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# mdadm -C -a yes /dev/md001 -l 0 -n 2 /dev/sd{b,c}1 #将sdb1和sdc1分区RAID0级别，使用"-n"指定设备个数，使用"-l"指定RAID级别，使用"-C -a yes"表示初始化创建的意思。
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md001 started.
mdadm: timeout waiting for /dev/md001
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# cat /proc/mdstat #观察md的状态
Personalities : [raid0]
md1 : active raid0 sdc1[1] sdb1[0]
209582080 blocks super 1.2 512k chunks
unused devices: <none>
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# ll /dev/md* #我们会发现多了一个块设备，但没有以我定义的"/dev/md001"来命名！
brw-rw---- 1 root disk 9, 1 Aug 21 01:50 /dev/md1
[root@yinzhengjie.com ~]#
3>.使用mdadm命令查看RAID设备的详细信息
[root@yinzhengjie.com ~]# mdadm -D /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Fri Aug 21 01:50:32 2020
Raid Level : raid0 #RAID级别是"raid 0"
Array Size : 209582080 (199.87 GiB 214.61 GB) #这里的总容量是200G左右
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Update Time : Fri Aug 21 01:50:32 2020
State : clean #目前状态是"clean"，
Active Devices : 2 #活动设备是2个
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Chunk Size : 512K #组块大小是512K
Consistency Policy : none
Name : yinzhengjie.com:001 (local to host yinzhengjie.com)
UUID : e7e1a4a7:f73b2990:a52b16b3:92be0561 #注意观察这个UUID哈，下面也会用到
Events : 0
Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
[root@yinzhengjie.com ~]#
4>.为RAID设备创建文件系统
[root@yinzhengjie.com ~]# mkfs.xfs /dev/md1 #我们将RAID 0设备格式化文件系统类型为XFS。
meta-data=/dev/md1 isize=512 agcount=16, agsize=3274624 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=52393984, imaxpct=25
= sunit=128 swidth=256 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=25584, version=2
= sectsz=512 sunit=8 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# blkid /dev/sd{b,c}1 #查看sdb1和sdc1分区都用一个统一的UUID，和上面的RAID设备的UUID完全相同。但这2个分区也有各自独立的UUID编号，当然，类型均为"linux_raid_member"
/dev/sdb1: UUID="e7e1a4a7-f73b-2990-a52b-16b392be0561" UUID_SUB="595fb659-a792-aaac-3a2d-800b3e0795ac" LABEL="yinzhengjie.com:001" TYPE="linux_raid_member"
/dev/sdc1: UUID="e7e1a4a7-f73b-2990-a52b-16b392be0561" UUID_SUB="78244c8b-f961-577f-9d32-af6c474e9f2b" LABEL="yinzhengjie.com:001" TYPE="linux_raid_member"
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# blkid /dev/md1 #我们也可以看到RAID 0设备(/dev/sdb1)的文件系统类型为XFS。
/dev/md1: UUID="bc7d4ffa-439e-4544-b59e-58d10228569c" TYPE="xfs"
[root@yinzhengjie.com ~]#
5>.挂载RAID设备
[root@yinzhengjie.com ~]# mkdir -pv /yinzhengjie/raid #创建挂载点
mkdir: created directory ‘/yinzhengjie/raid’
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# tail -1 /etc/fstab #你可以使用"mount"命令手动挂载，但我推荐大家写在配置文件中，这样重启服务器时会自动帮咱们挂载的.
UUID=bc7d4ffa-439e-4544-b59e-58d10228569c /yinzhengjie/raid xfs defaults,noatime,nodiratime 0 0
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# mount -a #我们使用该命令可以帮咱们实现自动挂载
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 500G 14G 486G 3% /
devtmpfs 2.0G 0 2.0G 0% /dev
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 2.0G 12M 2.0G 1% /run
tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/sda2 1014M 133M 882M 14% /boot
/dev/mapper/centos-yinzhengjie 1.6T 1.4G 1.6T 1% /yinzhengjie
tmpfs 394M 0 394M 0% /run/user/0
/dev/md1 200G 33M 200G 1% /yinzhengjie/raid
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]#
6>.测试RAID 0设备的写入速度
[root@yinzhengjie.com ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 500G 14G 486G 3% /
devtmpfs 2.0G 0 2.0G 0% /dev
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 2.0G 12M 2.0G 1% /run
tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/sda2 1014M 133M 882M 14% /boot
/dev/mapper/centos-yinzhengjie 1.6T 1.4G 1.6T 1% /yinzhengjie
tmpfs 394M 0 394M 0% /run/user/0
/dev/md1 200G 33M 200G 1% /yinzhengjie/raid
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/zero of=/yinzhengjie/raid/test.log bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 4.57999 s, 234 MB/s
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/zero of=/yinzhengjie/test2.log bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 9.90687 s, 108 MB/s
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/dev/zero of=/yinzhengjie/raid/test.log bs=1M count=1024
7>.测试RAID 0设备的读取速度
[root@yinzhengjie.com ~]# free -h
total used free shared buff/cache available
Mem: 3.8G 254M 3.3G 11M 297M 3.3G
Swap: 0B 0B 0B
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/yinzhengjie/test2.log of=/dev/null
2097152+0 records in
2097152+0 records out
1073741824 bytes (1.1 GB) copied, 3.84986 s, 279 MB/s
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# free -h
total used free shared buff/cache available
Mem: 3.8G 257M 2.3G 11M 1.3G 3.3G
Swap: 0B 0B 0B
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# sync; echo 1 > /proc/sys/vm/drop_caches
[root@yinzhengjie.com ~]# sync; echo 2 > /proc/sys/vm/drop_caches
[root@yinzhengjie.com ~]# sync; echo 3 > /proc/sys/vm/drop_caches
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# free -h
total used free shared buff/cache available
Mem: 3.8G 252M 3.5G 11M 141M 3.4G
Swap: 0B 0B 0B
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/yinzhengjie/raid/test.log of=/dev/null
2097152+0 records in
2097152+0 records out
1073741824 bytes (1.1 GB) copied, 2.79886 s, 384 MB/s
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# free -h
total used free shared buff/cache available
Mem: 3.8G 252M 2.5G 11M 1.1G 3.3G
Swap: 0B 0B 0B
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]#
[root@yinzhengjie.com ~]# dd if=/yinzhengjie/raid/test.log of=/dev/null
8>.重启服务器后再次查看挂载情况(编辑"/etc/fstab"文件后，虽说可以使用"mount -a"命令使之立即生效，但生产环境务必要重启服务器进行测试哟)
[root@yinzhengjie.com ~]# lsblk /dev/sd{b,c} #此处我们只看磁盘/dev/sdb和/dev/sdc这两块设备信息。
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sdb 8:16 0 600G 0 disk
└─sdb1 8:17 0 100G 0 part
└─md1 9:1 0 199.9G 0 raid0 /yinzhengjie/raid
sdc 8:32 0 400G 0 disk
└─sdc1 8:33 0 100G 0 part
└─md1 9:1 0 199.9G 0 raid0 /yinzhengjie/raid
[root@yinzhengjie.com ~]#
