Linux下如何用fdisk新建分区

fdisk磁盘分区工具
 
1.首先查看硬盘信息
 
fdisk -l 如果有硬盘有剩余空间就可以对其进行分区
 
 
[root@bogon 桌面]# fdisk -l
 
Disk /dev/sda: 85.9 GB, 85899345920 bytes
 255 heads, 63 sectors/track, 10443 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: 0x000471ad
 
  Device Boot      Start        End      Blocks  Id  System
 /dev/sda1  *          1          26      204800  83  Linux
 Partition 1 does not end on cylinder boundary.
 /dev/sda2              26        3851    30720000  83  Linux
 /dev/sda3            3851        4106    2048000  82  Linux swap / Solaris
 /dev/sda4            4106      10444    50912256    5  Extended
 /dev/sda5            4106      10444    50911232  83  Linux
 
Disk /dev/sdb: 21.5 GB, 21474836480 bytes
 255 heads, 63 sectors/track, 2610 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: 0x00000000
 #从上面看出/dev/sda空间已经用完了，/dev/sdb没有使用。
 
下面我们对/dev/sdb 进行分区
 
[root@bogon 桌面]# 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 0xfaa2aa49.
 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): 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)
 fdisk选中/dev/sdb 输入m所有基本选项都出现，输入n新建分区
 
Command (m for help): n
 Command action
    e  extended
    p  primary partition (1-4)有扩展分区和主分区，逻辑分区在扩展分区中建立。注意到括号中的1-4，最多只能建四个主分区（包括扩展分区）。先建一个主分区：
 
Command (m for help): n
 Command action
    e  extended
    p  primary partition (1-4)
 p #建主分区
 Partition number (1-4): 1 #分区号为1
 First cylinder (1-2610, default 1): #直接回车默认从第一个柱面开始划分
 Using default value 1
 Last cylinder, +cylinders or +size{K,M,G} (1-2610, default 2610): +2G #加空间大小，这里有很多种选择：+后面单位可以接M，G，K（记得要大写）表示划分你所加的空间，也可以是柱面数。不管怎样都不能超过该磁盘剩余的空间否则无效。
 
Command (m for help): p #分好后查看分区信息，刚所做的所有一目了然。
 
Disk /dev/sdb: 21.5 GB, 21474836480 bytes
 255 heads, 63 sectors/track, 2610 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: 0xfaa2aa49
 
  Device Boot      Start        End      Blocks  Id  System
 /dev/sdb1              1        262    2104483+  83  Linux
 
同上所述建立扩展分区：
 
Command (m for help): n
 Command action
    e  extended
    p  primary partition (1-4)
 e #建立扩展分区
 Partition number (1-4): 4
 First cylinder (263-2610, default 263):
Using default value 263
 Last cylinder, +cylinders or +size{K,M,G} (263-2610, default 2610): +4G
 
Command (m for help): p
 
Disk /dev/sdb: 21.5 GB, 21474836480 bytes
 255 heads, 63 sectors/track, 2610 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: 0xfaa2aa49
 
  Device Boot      Start        End      Blocks  Id  System
 /dev/sdb1              1        262    2104483+  83  Linux
 /dev/sdb4            263        785    4200997+  5  Extended
 
扩展分区建好我们就可以在扩展分区建立逻辑分区了
 
Command (m for help): n
 Command action
    l  logical (5 or over)
    p  primary partition (1-4)
 l #建逻辑分区
 First cylinder (263-785, default 263):
Using default value 263
 Last cylinder, +cylinders or +size{K,M,G} (263-785, default 785): +2G
 
Command (m for help): p
 
Disk /dev/sdb: 21.5 GB, 21474836480 bytes
 255 heads, 63 sectors/track, 2610 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: 0xfaa2aa49
 
  Device Boot      Start        End      Blocks  Id  System
 /dev/sdb1              1        262    2104483+  83  Linux
 /dev/sdb4            263        785    4200997+  5  Extended
 /dev/sdb5            263        524    2104483+  83  Linux上面显示已经建好一个主分区，一个逻辑分区，但是这些现在还没有生效我们需要保存退出。
 
Command (m for help): w #保存退出
 The partition table has been altered!
 
Calling ioctl() to re-read partition table.
 Syncing disks.
 
[root@bogon 桌面]# fdisk -l
 
Disk /dev/sda: 85.9 GB, 85899345920 bytes
 255 heads, 63 sectors/track, 10443 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: 0x000471ad
 
  Device Boot      Start        End      Blocks  Id  System
 /dev/sda1  *          1          26      204800  83  Linux
 Partition 1 does not end on cylinder boundary.
 /dev/sda2              26        3851    30720000  83  Linux
 /dev/sda3            3851        4106    2048000  82  Linux swap / Solaris
 /dev/sda4            4106      10444    50912256    5  Extended
 /dev/sda5            4106      10444    50911232  83  Linux
 
Disk /dev/sdb: 21.5 GB, 21474836480 bytes
 255 heads, 63 sectors/track, 2610 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: 0xfaa2aa49
 
  Device Boot      Start        End      Blocks  Id  System
 /dev/sdb1              1        262    2104483+  83  Linux
 /dev/sdb4            263        785    4200997+  5  Extended
 /dev/sdb5            263        524    2104483+  83  Linux
 
再次查看就看到了/dev/sdb的分区信息，虽然现在我们看到进行分区了，但是内核kenel还没有识别为了不要重启将分区表写入kenel我们要用到partprobe工具：使kenel重新读取分区表。[root@bogon 桌面]# partprobe
Warning: WARNING: the kernel failed to re-read the partition table on /dev/sda (设备或资源忙).  As a result, it may not reflect all of your changes until after reboot.
 
kenel识别分区表后，我们还不能使用它要对其进行格式化。mkfs.加文件系统格式，扩展分区是不能格式化的。
 
[root@bogon 桌面]# mkfs.ext4 /dev/sdb1 #格式化成ext4文件格式（要分区格式化，不能将整个硬盘格式化）
 mke2fs 1.41.12 (17-May-2010)
 文件系统标签=
 操作系统:Linux
 块大小=4096 (log=2)
 分块大小=4096 (log=2)
 Stride=0 blocks, Stripe width=0 blocks
 131648 inodes, 526120 blocks
 26306 blocks (5.00%) reserved for the super user
 第一个数据块=0
 Maximum filesystem blocks=541065216
 17 block groups
 32768 blocks per group, 32768 fragments per group
 7744 inodes per group
 Superblock backups stored on blocks:
    32768, 98304, 163840, 229376, 294912
 
正在写入inode表: 完成                           
Creating journal (16384 blocks): 完成
 Writing superblocks and filesystem accounting information: 完成
 
This filesystem will be automatically checked every 30 mounts or
 180 days, whichever comes first.  Use tune2fs -c or -i to override.
 [root@bogon 桌面]# mkfs.ext4 /dev/sdb5 #格式化逻辑分区
 mke2fs 1.41.12 (17-May-2010)
 文件系统标签=
 操作系统:Linux
 块大小=4096 (log=2)
 分块大小=4096 (log=2)
 Stride=0 blocks, Stripe width=0 blocks
 131648 inodes, 526120 blocks
 26306 blocks (5.00%) reserved for the super user
 第一个数据块=0
 Maximum filesystem blocks=541065216
 17 block groups
 32768 blocks per group, 32768 fragments per group
 7744 inodes per group
 Superblock backups stored on blocks:
    32768, 98304, 163840, 229376, 294912
 
正在写入inode表: 完成                           
Creating journal (16384 blocks): 完成
 Writing superblocks and filesystem accounting information: 完成
 
This filesystem will be automatically checked every 39 mounts or
 180 days, whichever comes first.  Use tune2fs -c or -i to override.
 
格式化后就可以使用了
 
[root@bogon 桌面]# mkdir /bak
 [root@bogon 桌面]# mount -o loop /dev/sdb1 /bak #挂载该分区到/bak
 [root@bogon 桌面]# df -TH #查看当前硬盘挂载信息
 文件系统    类型      容量  已用  可用 已用%% 挂载点
 /dev/sda5    ext4      52G  3.9G    45G  8% /
 tmpfs        tmpfs    528M  279k  528M  1% /dev/shm
 /dev/sda1    ext4    204M    28M  166M  15% /boot
 /dev/sda2    ext4      31G  2.9G    27G  10% /usr
 .host:/    vmhgfs    144G    41G  104G  29% /mnt/hgfs
 /ios/RHEL6.3.iso
            iso9660    3.2G  3.2G      0 100% /guazai
 /dev/sdb1    ext4    2.2G    71M  2.0G  4% /bak