fdisk使用

0）fdisk /dev/sda进入交互式命令行

1）显示当前分区

p

2）创建新分区

Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (524-60801, default 524):
Using default value 524
Last cylinder, +cylinders or +size{K,M,G} (524-60801, default 60801): +20G

Command (m for help): p

Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 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: 0x000b52a5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1         523     4200966   83  Linux
/dev/sda2             524        3135    20980890   83  Linux

//写入分区表，这一步不能少，否则分区表不会被修改！

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.



3）刷新分区表

partprobe或系统重启

[root@ihost ~]# 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.
[root@ihost ~]# reboot

Broadcast message from [e-mail]
    (/dev/pts/0) at 11:00 ...

The system is going down for reboot NOW!