磁盘分区的删除

使用fdisk  设备名  进入fdisk 界面。

[root@zeng ~]# fdisk /dev/sdb

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').

//先来查看下该设备的分区表，这是在执行其他操作前的好习惯。

Command (m for help): p

Disk /dev/sdb: 8589 MB, 8589934592 bytes

255 heads, 63 sectors/track, 1044 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: 0xd7ea6b16

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               1        1044     8385898+   5  Extended

/dev/sdb5               1        1044     8385867   83  Linux

//有两个分区，一个扩展分区/dev/sdb1,还有一个逻辑分区/dev/sda5。

使用d 来删除分区.

Command (m for help): d 

Partition number (1-5): 5  //输入要删除的分区好5即代表/dev/sdb5.

Command (m for help): p

Disk /dev/sdb: 8589 MB, 8589934592 bytes

255 heads, 63 sectors/track, 1044 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: 0xd7ea6b16

   Device Boot      Start         End      Blocks   Id  System

// /dev/sdb1               1        1044     8385898+   5  Extended

逻辑分区/dev/sdb5 已经被删除了,现在我们再来把扩展分区也给删除掉.

Command (m for help): d

Selected partition 1

因为只剩下最后一个分区，所以fdisk 自动的选中该分区.

Command (m for help): p

Disk /dev/sdb: 8589 MB, 8589934592 bytes

255 heads, 63 sectors/track, 1044 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: 0xd7ea6b16

   Device Boot      Start         End      Blocks   Id  System

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: Device or resource busy.

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

在执行分区删除的时候出现了一个错误，说的是系统无法加载信息的分区表，因为设备在忙。因为

我粗心大意在删除分区前，没有把该分区卸载掉。下面来补做这个工作。

[root@zeng ~]# umount /dev/sdb5

查看下设备的分区表，ok 没问题.

[root@zeng ~]# fdisk  /dev/sdb

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): p

Disk /dev/sdb: 8589 MB, 8589934592 bytes

255 heads, 63 sectors/track, 1044 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: 0xd7ea6b16

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): q