磁盘阵列Raid0，Raid1，Raid10，Raid5的创建

项目	Raid0	Raid1	Raid10	Raid5	Raid6
最少磁盘数	2	2	4	3	4
最大容错磁盘数(1)	无	n-1	n/2	1	2
资料安全性(1)	完全沒有	最佳	最佳	好	比RAID5 好
理论写入效能(2)	n	1	n/2	<n-1	<n-2
理论读出效能(2)	n	n	n	<n-1	<n-2
可用容量(3)	n	1	n/2	n-1	n-2
一般应用	强调效能但资料不重要的环境	资料与备份服务器、云系统常用	资料与备份服务器、云系统常用	资料与备份	资料与备份

Raid0

fdisk /dev/sdb(分区)

[root@localhost ~]# fdisk /dev/sdb
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xa2d567b3.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.

Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
         switch off the mode (command 'c') and change display units to
         sectors (command 'u').

Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-652, default 1): 
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-652, default 652): +1G

Command (m for help): t
Selected partition 1
Hex code (type L to list codes): l

 0  Empty           24  NEC DOS         81  Minix / old Lin bf  Solaris        
 1  FAT12           39  Plan 9          82  Linux swap / So c1  DRDOS/sec (FAT-
 2  XENIX root      3c  PartitionMagic  83  Linux           c4  DRDOS/sec (FAT-
 3  XENIX usr       40  Venix 80286     84  OS/2 hidden C:  c6  DRDOS/sec (FAT-
 4  FAT16 <32M      41  PPC PReP Boot   85  Linux extended  c7  Syrinx         
 5  Extended        42  SFS             86  NTFS volume set da  Non-FS data    
 6  FAT16           4d  QNX4.x          87  NTFS volume set db  CP/M / CTOS / .
 7  HPFS/NTFS       4e  QNX4.x 2nd part 88  Linux plaintext de  Dell Utility   
 8  AIX             4f  QNX4.x 3rd part 8e  Linux LVM       df  BootIt         
 9  AIX bootable    50  OnTrack DM      93  Amoeba          e1  DOS access     
 a  OS/2 Boot Manag 51  OnTrack DM6 Aux 94  Amoeba BBT      e3  DOS R/O        
 b  W95 FAT32       52  CP/M            9f  BSD/OS          e4  SpeedStor      
 c  W95 FAT32 (LBA) 53  OnTrack DM6 Aux a0  IBM Thinkpad hi eb  BeOS fs        
 e  W95 FAT16 (LBA) 54  OnTrackDM6      a5  FreeBSD         ee  GPT            
 f  W95 Ext'd (LBA) 55  EZ-Drive        a6  OpenBSD         ef  EFI (FAT-12/16/
10  OPUS            56  Golden Bow      a7  NeXTSTEP        f0  Linux/PA-RISC b
11  Hidden FAT12    5c  Priam Edisk     a8  Darwin UFS      f1  SpeedStor      
12  Compaq diagnost 61  SpeedStor       a9  NetBSD          f4  SpeedStor      
14  Hidden FAT16 <3 63  GNU HURD or Sys ab  Darwin boot     f2  DOS secondary  
16  Hidden FAT16    64  Novell Netware  af  HFS / HFS+      fb  VMware VMFS    
17  Hidden HPFS/NTF 65  Novell Netware  b7  BSDI fs         fc  VMware VMKCORE 
18  AST SmartSleep  70  DiskSecure Mult b8  BSDI swap       fd  Linux raid auto
1b  Hidden W95 FAT3 75  PC/IX           bb  Boot Wizard hid fe  LANstep        
1c  Hidden W95 FAT3 80  Old Minix       be  Solaris boot    ff  BBT            
1e  Hidden W95 FAT1
Hex code (type L to list codes): fd  Linux raid auto
Changed system type of partition 1 to fd (Linux raid autodetect)

Command (m for help): p

Disk /dev/sdb: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xa2d567b3

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1         132     1060258+  fd  Linux raid autodetect

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

fdisk /dev/sdc(和sdb一样)

partx -a /dev/sdb1 /dev/sdb（同步分区情况）

partx -a /dev/sdc1 /dev/sdc（同步分区情况）

fdisk -l /dev/sdb /dev/sdc（查看现在的状态）

[root@localhost ~]# fdisk -l /dev/sdb /dev/sdc

Disk /dev/sdb: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xa2d567b3

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1         132     1060258+  fd  Linux raid autodetect

Disk /dev/sdc: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x53685b07

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1         132     1060258+  fd  Linux raid autodetect

mdadm -C /dev/md0 -ayes -l0 -n2 /dev/sd{b,c}1（开始创建RAID0）

[root@localhost ~]# mdadm -C /dev/md0 -ayes -l0 -n2 /dev/sd{b,c}1
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.

cat /proc/mdstat（查看raid0 状态）

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid0] 
md0 : active raid0 sdc1[1] sdb1[0]
      2119680 blocks super 1.2 512k chunks
      
unused devices: <none>

mdadm -D /dev/md0（查看raid0 状态）

[root@localhost ~]# mdadm -D /dev/md0
/dev/md0:
        Version : 1.2
  Creation Time : Sat Oct  6 10:29:44 2018
     Raid Level : raid0
     Array Size : 2119680 (2.02 GiB 2.17 GB)
   Raid Devices : 2
  Total Devices : 2
    Persistence : Superblock is persistent

    Update Time : Sat Oct  6 10:29:44 2018
          State : clean 
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

     Chunk Size : 512K

           Name : localhost.localdomain:0  (local to host localhost.localdomain)
           UUID : 038b42e0:54219821:617dd9f0:029825b1
         Events : 0

    Number   Major   Minor   RaidDevice State
       0       8       17        0      active sync   /dev/sdb1
       1       8       33        1      active sync   /dev/sdc1

（添加raid1 到RAID 配置文件/etc/mdadm.conf并修改，以下）

touch /etc/mdadm.conf

echo DEVICE /dev/sd{b,c}1 >> /etc/mdadm.conf

mdadm -Ds >> /etc/mdadm.conf

vim /etc/mdadm.conf

[root@localhost ~]# vim /etc/mdadm.conf                        
  1 DEVICE /dev/sdb1 /dev/sdc1
  # 将中间一段改为level=raid0 num-devices=2
  2 ARRAY /dev/md0 level=raid0 num-devices=2 UUID=038b42e0:54219821:617dd9f0:029825b1

mkfs.ext4 /dev/md0（格式化磁盘阵列）

[root@localhost ~]# mkfs.ext4 /dev/md0
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
132736 inodes, 529920 blocks
26496 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=545259520
17 block groups
32768 blocks per group, 32768 fragments per group
7808 inodes per group
Superblock backups stored on blocks: 
        32768, 98304, 163840, 229376, 294912

Writing inode tables: done                            
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 38 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

（建立挂载点并挂载，以下）

mkdir /mnt/raid0

mount /dev/md0 /mnt/raid0

[root@localhost ~]# df -TH
Filesystem                   Type     Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root ext4      19G  6.5G   12G  37% /
tmpfs                        tmpfs    523M   78k  523M   1% /dev/shm
/dev/sda1                    ext4     508M   36M  446M   8% /boot
/dev/sr0                     iso9660  4.5G  4.5G     0 100% /media/CentOS_6.5_Final
/dev/md0                     ext4     2.2G   71M  2.0G   4% /mnt/raid0

vim /etc/fstab(填上最后一行信息)

[root@localhost ~]# vim /etc/fstab
  1 
  2 #
  3 # /etc/fstab
  4 # Created by anaconda on Thu Aug 30 19:30:32 2018
  5 #
  6 # Accessible filesystems, by reference, are maintained under '/dev/disk'
  7 # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
  8 #
  9 /dev/mapper/VolGroup-lv_root /                       ext4    defaults        1 1
 10 UUID=7d586269-560b-42c2-b134-90177acbfcc5 /boot                   ext4    defaults
         1 2
 11 /dev/mapper/VolGroup-lv_swap swap                    swap    defaults        0 0
 12 tmpfs                   /dev/shm                tmpfs   defaults        0 0
 13 devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
 14 sysfs                   /sys                    sysfs   defaults        0 0
 15 proc                    /proc                   proc    defaults        0 0
 16 /dev/md0                /mnt/raid0                  ext4    defaults        0 0

reboot（重启一下）

[root@localhost ~]# reboot

Broadcast message from [email protected]
        (/dev/pts/0) at 10:47 ...

The system is going down for reboot NOW!

df -TH（测试开机是否自动挂载）

[root@localhost ~]# df -TH
Filesystem                   Type     Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root ext4      19G  6.5G   12G  37% /
tmpfs                        tmpfs    523M   78k  523M   1% /dev/shm
/dev/sda1                    ext4     508M   36M  446M   8% /boot
/dev/md0                     ext4     2.2G   71M  2.0G   4% /mnt/raid0
/dev/sr0                     iso9660  4.5G  4.5G     0 100% /media/CentOS_6.5_Final

扩展：

测试分别写入1G的文件（dd生成）和1.1G（换算成M，必须是整数）的文件，观察现象;

[root@localhost ~]# time dd if=/dev/zero of=/test01.txt bs=1G count=1           
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 68.232 s, 15.7 MB/s
dd: closing input file `/dev/zero': Bad file descriptor

real    1m8.600s
user    0m0.002s
sys     0m10.419s
[root@localhost ~]# 
[root@localhost ~]# time dd if=/dev/zero of=/mnt/raid0/test02.txt bs=2099M count=1 
dd: writing `/mnt/raid0/test02.txt': No space left on device
0+1 records in
0+0 records out
975536128 bytes (976 MB) copied, 76.5786 s, 12.7 MB/s

real    1m16.918s
user    0m0.001s
sys     0m9.488s

Raid1，Raid10，Raid5的创建,,,,下次再更新~~~~~~~~

磁盘阵列Raid0，Raid1，Raid10，Raid5的创建

猜你喜欢