极客笔记Linux fdisk命令：分区表管理。
Linux fdisk命令 功能描述
使用fdisk命令可以对磁盘进行分区，它采用传统的问答式界面，除此之外还可以查看磁盘分区的详细信息。
Linux fdisk命令 语法
fdisk [选项] [设备]
命令中各选项的含义如表所示。
在fdisk命令的交互式操作方式下有许多子命令，如表所示。
Linux fdisk命令 示例
在磁盘/dev/sda中创建、删除、查看分区及转换分区类型
（1）进入fdisk，列出所有子命令
[root@rhel ～]# fdisk /dev/sda
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): m
Command action
a toggle a bootable flag
b edit bsd disklabel
c toggle the dos compatibility flag
d delete a partition
l list known partition types
m print this menu
n add a new partition
o create a new empty DOS partition table
p print the partition table
q quit without saving changes
s create a new empty Sun disklabel
t change a partition's system id
u change display/entry units
v verify the partition table
w write table to disk and exit
x extra functionality(experts only)
（2）显示磁盘分区信息
Command(m for help): p
Disk /dev/sda: 536.9 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 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: 0x00034c36
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 102400 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 13 19595 157286400 83 Linux
/dev/sda3 19595 19856 2097152 82 Linux swap/Solaris
磁盘分区信息描述如表所示。
磁盘分区的表示方法如下。
Device：磁盘分区设备名，如/dev/sda1。
- Boot：表示引导分区，在上面的例子中/dev/sda1是引导分区。
- Start：表示一个分区的开始柱面。
- End：表示一个分区的结束柱面。
- Id：一个两位的十六进制，表示分区类型。
- System:Id所定义的分区类型。
- Blocks（容量）：表示分区容量，其单位是块，默认一个块是1KB。
（3）创建和删除主分区
在创建磁盘分区时，需要指定结束柱面，具体方法如表所示。
Command(m for help): n
//在此输入n，开始创建分区
Command action
e extended //创建扩展分区
p primary partition(1-4) //创建主分区
p
//在此输入p，开始创建主分区
Selected partition 4
First cylinder (19856-65270, default 19856):
//直接按回车键，从磁盘剩余起始柱面开始创建分区
Using default value 19856
Last cylinder, +cylinders or+size{K, M, G}(19856-65270, default 65270):30000
//在此输入30000，代表分区结束柱面数是30000
Command(m for help): p
Disk /dev/sda: 536.9 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 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: 0x00034c36
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 102400 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 13 19595 157286400 83 Linux
/dev/sda3 19595 19856 2097152 82 Linux swap/Solaris
/dev/sda4 19856 30000 81488024 83 Linux
//查看分区信息，可以看到新创建的主分区为/dev/sda4
Command(m for help): n
You must delete some partition and add an extended partition first
//4个分区已满，再也无法创建第5个分区
Command(m for help): d
//在此输入d，开始删除主分区
Partition number(1-4):4
//输入分区号码，在此输入4，说明要删除/dev/sda4分区
Command(m for help): p
Disk /dev/sda: 536.9 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 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: 0x00034c36
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 102400 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 13 19595 157286400 83 Linux
/dev/sda3 19595 19856 2097152 82 Linux swap/Solaris
//再次查看分区信息，之前创建的主分区/dev/sda4已经被删除
（4）创建扩展分区和逻辑驱动器
Command(m for help): n
Command action
e extended
p primary partition(1-4)
e
//在此输入e，开始创建扩展分区
Selected partition 4
First cylinder (19856-65270, default 19856):
//直接按回车键，从磁盘剩余起始柱面开始创建扩展分区
Using default value 19856
Last cylinder, +cylinders or +size{K, M, G} (19856-65270, default 65270):
//直接按回车键，则从第19856个柱面到最后一个柱面均为扩展分区
Using default value 65270
Command(m for help): n
//在此输入n，开始创建第一个逻辑驱动器
First cylinder (19856-65270, default 19856):
//直接按回车键，从磁盘剩余起始柱面开始创建逻辑驱动器
Using default value 19856
Last cylinder, +cylinders or+size{K, M, G}(19856-65270, default 65270): +100G
//在此输入“+100G”，代表创建容量为100GB的逻辑驱动器
Command(m for help): n
//在此输入n，开始创建第二个逻辑驱动器
First cylinder (32015-65270, default 32015):
//直接按回车键，从磁盘剩余起始柱面开始创建逻辑驱动器
Using default value 32015
Last cylinder, +cylinders or +size{K, M, G} (32015-65270, default 65270):
//直接按回车键，则从第32015个柱面到最后一个柱面均为该逻辑驱动器
Using default value 65270
Command(m for help): p
Disk /dev/sda: 536.9 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 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: 0x00034c36
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 102400 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 13 19595157286400 83 Linux
/dev/sda3 19595 19856 2097152 82 Linux swap/Solaris
/dev/sda4 19856 65270364794299 5 Extended
/dev/sda5 19856 32910104862567+ 83 Linux
/dev/sda6 32911 65270259931668+ 83 Linux
//再次查看分区信息，可以看到刚才所创建的扩展分区/dev/sda4和逻辑驱动器/dev/sda5、/dev/sda6
（5）查看并转换分区类型
Command(m for help): 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
Command(m for help): t
//在此输入t，开始转换分区类型
Partition number(1-6):6
//输入分区号码，在此输入6，说明要转换/dev/sda6分区的类型
Hex code(type L to list codes): c
Changed system type of partition 6 to c (W95 FAT32 (LBA))
//转换6号分区类型为W95 FAT32 (LBA)
Command(m for help): p
Disk /dev/sda: 536.9 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 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: 0x00034c36
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 102400 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 13 19595157286400 83 Linux
/dev/sda3 19595 19856 2097152 82 Linux swap/Solaris
/dev/sda4 19856 65270364794299 5 Extended
/dev/sda5 19856 32910104862567+ 83 Linux
/dev/sda6 32911 65270259931668+ c W95 FAT32(LBA)
//再次查看分区信息，可以看到/dev/sda6分区类型为W95 FAT32 (LBA)
（6）保存分区设置信息，并退出fdisk
Command(m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16： 设备或资源忙．
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
（7）在非交互式界面下显示当前磁盘的分区信息
[root@rhel ～]# fdisk -l /dev/sda
Disk /dev/sda: 536.9 GB, 536870912000 bytes
255 heads, 63 sectors/track, 65270 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: 0x00034c36
Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 102400 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 13 19595 157286400 83 Linux
/dev/sda3 19595 19856 2097152 82 Linux swap/Solaris
/dev/sda4 19856 65270 364794299 5 Extended
/dev/sda5 19856 32910 104862567+ 83 Linux
/dev/sda6 32911 65270 259931668+ c W95 FAT32(LBA)
（8）重启计算机系统
使用以下命令重新启动Linux系统。
[root@rhel ～]# init 6