装好CentOS后，发现空间太小，怎样才能增加硬盘容量？那就是再建一个硬盘：
打开虚拟经济的设置添加硬盘
查看现有的磁盘空间
fdisk -l
[root@localhost ~]# fdisk -l Disk /dev/sda: 21.5 GB, bytes
heads, sectors/track, cylinders
Units = cylinders of * = bytes
Sector size (logical/physical): bytes / bytes
I/O size (minimum/optimal): bytes / bytes
Disk identifier: 0x000e4bd8 Device Boot Start End Blocks Id System
/dev/sda1 * Linux
Partition does not end on cylinder boundary.
/dev/sda2 8e Linux LVM Disk /dev/sdb: MB, bytes
heads, sectors/track, cylinders
Units = cylinders of * = bytes
Sector size (logical/physical): bytes / bytes
I/O size (minimum/optimal): bytes / bytes
Disk identifier: 0x00000000
我添加的是/dev/sdb
给新加的硬盘进行分区
fdisk /dev/sdb
输入m ，可以查看帮助信息
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) Command (m for help):
增加新的分区
command (m for help):n
选择基本信息分区，输入：p
Command (m for help): n
Command action
e extended
p primary partition (-)
回车
First cylinder (-,default ):Enter
（这是回车是指分的默认大小）
写入并退出
command (m for help):w
然后格式化磁盘分区
用ext4格式对/dev/sdb1进入格式化
mkfs.ext4 /dev/sdb1
[root@localhost ~]# mkfs.ext4 /dev/sdb
mke2fs 1.41.12 (17-May-2010)
/dev/sdb is entire device, not just one partition!
无论如何也要继续? (y,n) y
/dev/sdb 已经挂载;will not make a 文件系统 here!
[root@localhost ~]#
因为我的扩展盘符已经挂上去了，在占用状态。
挂载分区
先创建一个挂载点
mkdir /work
mount -t ext4 /dev/sdb1/work
查看挂载状态
df -h
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root 18G 11G .2G % /
tmpfs 932M 72K 932M % /dev/shm
/dev/sda1 485M 40M 421M % /boot
/dev/sdb .0G 138M .6G % /work
[root@localhost ~]#
将挂载的目录加入开机自动挂载
/dev/sdb1 /work ext4 errors=remount-ro
完成