2. RAID 建立與格式化

練習(xí)這段的時(shí)候，千萬不要在本機(jī)（自己的電腦主系統(tǒng)）上練習(xí)，
以免一個(gè)失手造成系統(tǒng)無法正常開機(jī)。請(qǐng)用虛擬機(jī)器練習(xí)。

1. 觀看分割區(qū)資訊。
[root@station8 ~]# fdisk /dev/sda -l

Disk /dev/sda: 4294 MB, 4294967296 bytes
255 heads, 63 sectors/track, 522 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          25      200781   83  Linux
/dev/sda2              26         286     2096482+  83  Linux
/dev/sda3             287         350      514080   83  Linux
/dev/sda4             351         522     1381590    5  Extended
/dev/sda5             351         401      409626   83  Linux
/dev/sda6             402         414      104391   fd  Linux raid autodetect
/dev/sda7             415         427      104391   fd  Linux raid autodetect
/dev/sda8             428         440      104391   82  Linux swap / Solaris

上面的標(biāo)籤資訊寫 Linux raid autodetect 就表示已經(jīng)是 raid 的分割區(qū)了。
因?yàn)橐粋€(gè)raid 至少要2 個(gè)分割區(qū)來組成，以上面的例子，sda6與sda7共組成一個(gè) raid 分割區(qū)。

2. 新建分割區(qū)sda9與sda10。(不會(huì)新建分割區(qū)的話，請(qǐng)參考 我的小屋的 [RHCT] 1.建立實(shí)體分割區(qū)與格式化的文章。)

[root@station8 ~]# fdisk /dev/sda -l
Disk /dev/sda: 4294 MB, 4294967296 bytes
255 heads, 63 sectors/track, 522 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          25      200781   83  Linux
/dev/sda2              26         286     2096482+  83  Linux
/dev/sda3             287         350      514080   83  Linux
/dev/sda4             351         522     1381590    5  Extended
/dev/sda5             351         401      409626   83  Linux
/dev/sda6             402         414      104391   fd  Linux raid autodetect
/dev/sda7             415         427      104391   fd  Linux raid autodetect
/dev/sda8             428         440      104391   82  Linux swap / Solaris
/dev/sda9             441         472      257008+  83  Linux
/dev/sda10            473         504      257008+  83  Linux


3. 替分割區(qū)sda9與sda10命名為 Linux raid autodetect
[root@station8 ~]# fdisk /dev/sda

Command (m for help): t (輸入t 以命名標(biāo)籤)
Partition number (1-10): 9 （選擇分割區(qū)sda9）
Hex code (type L to list codes): L (輸入L 顯示list)

0  Empty           1e  Hidden W95 FAT1 80  Old Minix       bf  Solaris        
1  FAT12           24  NEC DOS         81  Minix / old Lin c1  DRDOS/sec (FAT-
2  XENIX root      39  Plan 9          82  Linux swap / So c4  DRDOS/sec (FAT-
3  XENIX usr       3c  PartitionMagic  83  Linux           c6  DRDOS/sec (FAT-
4  FAT16 <32M      40  Venix 80286     84  OS/2 hidden C:  c7  Syrinx         
5  Extended        41  PPC PReP Boot   85  Linux extended  da  Non-FS data    
6  FAT16           42  SFS             86  NTFS volume set db  CP/M / CTOS / .
7  HPFS/NTFS       4d  QNX4.x          87  NTFS volume set de  Dell Utility   
8  AIX             4e  QNX4.x 2nd part 88  Linux plaintext df  BootIt         
9  AIX bootable    4f  QNX4.x 3rd part 8e  Linux LVM       e1  DOS access     
a  OS/2 Boot Manag 50  OnTrack DM      93  Amoeba          e3  DOS R/O        
b  W95 FAT32       51  OnTrack DM6 Aux 94  Amoeba BBT      e4  SpeedStor      
c  W95 FAT32 (LBA) 52  CP/M            9f  BSD/OS          eb  BeOS fs        
e  W95 FAT16 (LBA) 53  OnTrack DM6 Aux a0  IBM Thinkpad hi ee  EFI GPT        
f  W95 Ext'd (LBA) 54  OnTrackDM6      a5  FreeBSD         ef  EFI (FAT-12/16/
10  OPUS            55  EZ-Drive        a6  OpenBSD         f0  Linux/PA-RISC b
11  Hidden FAT12    56  Golden Bow      a7  NeXTSTEP        f1  SpeedStor      
12  Compaq diagnost 5c  Priam Edisk     a8  Darwin UFS      f4  SpeedStor      
14  Hidden FAT16 <3 61  SpeedStor       a9  NetBSD          f2  DOS secondary  
16  Hidden FAT16    63  GNU HURD or Sys ab  Darwin boot     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 （可以看到Linux raid autodetect 的代號(hào)是fd）
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            

Hex code (type L to list codes): fd (輸入fd)
Changed system type of partition 9 to fd (Linux raid autodetect)

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

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: 裝置或系統(tǒng)資源忙碌中.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
You have new mail in /var/spool/mail/root

(記得做完後還要再做一次，因?yàn)檫€有sda10分割區(qū)要命名。)


4.  記得更新資訊給核心。
[root@station8 ~]# partprobe


5. 新建一個(gè)RAID裝置，為RAID1 ，名為 /dev/md1 ，並且由sda9 與 sda10 組成。
(這邊是重點(diǎn)中的重點(diǎn)，會(huì)不會(huì)過就看這邊。)

[root@station8 ~]# mdadm  -C  /dev/md1   -l  1   -n 2  /dev/sda{9,10}
（-C /dev/md1 是新裝置的名稱，-l  1 是設(shè)定此RAID的等級(jí)為RAID1 ，
-n  2  是由2個(gè)分割區(qū)組成，由/dev/sda{9,10}兩個(gè)分割區(qū)組成。 ）

mdadm: /dev/sda9 appears to contain an ext2fs file system
    size=104320K  mtime=Mon Feb 14 17:11:42 2011
mdadm: /dev/sda9 appears to be part of a raid array:
    level=raid5 devices=2 ctime=Mon Feb 14 15:26:55 2011
mdadm: /dev/sda10 appears to contain an ext2fs file system
    size=104320K  mtime=Mon Feb 14 17:11:42 2011
mdadm: /dev/sda10 appears to be part of a raid array:
    level=raid5 devices=2 ctime=Mon Feb 14 15:26:55 2011

Continue creating array? (y/n) y  ( 輸入y )
mdadm: array /dev/md1 started.  ( 顯示已經(jīng)完成並啟動(dòng)。)


6. 完成後要使用當(dāng)然要格式化，使用mkfs 指令來格式化。
[root@station8 ~]# mkfs.ext3   /dev/md1
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
26104 inodes, 104320 blocks
5216 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=67371008
13 block groups
8192 blocks per group, 8192 fragments per group
2008 inodes per group
Superblock backups stored on blocks:
    8193, 24577, 40961, 57345, 73729

Writing inode tables: done                            
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 34 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.


7. 將 /dev/md1 掛載到 /data 底下。
[root@station8 ~]# mkdir  /data  (先建立/data目錄)
[root@station8 ~]# mount  -t  ext3  /dev/md1  /data  (掛載)
[root@station8 ~]# mount  (檢查是否有掛載上去)
/dev/sda5 on / type ext3 (rw,acl)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/sda3 on /var type ext3 (rw)
/dev/sda2 on /usr type ext3 (rw)
/dev/sda1 on /boot type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
/dev/sda13 on /opt/newapp type ext3 (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
/dev/md1 on /data type ext3 (rw)  ( 有掛載上去！)


確認(rèn)系統(tǒng)的RAID裝置：
[root@station8 ~]# mdadm --detail /dev/md
md0  md1  md2  
---------------------------------------------------------------------
至此就完成，重點(diǎn)是mdadm的指令與參數(shù)設(shè)定。
如果題目要求開機(jī)後自動(dòng)掛載，就把mount 中的 /dev/md1 on /data type ext3 (rw) 寫入
/etc/fstab中即可。並且使用 mount -o remount /dev/md1  /data  進(jìn)行檢查，
沒有錯(cuò)誤才能重開機(jī)。