linux(LVM)扩展根目录空间的操作步骤

LVM下添加根目录空间

一、linux下的fdisk工具进行分区。

用root用户登录到你的linux系统，查看你系统的分区

#fdisk -l

会出现以下的信息：

Disk /dev/sda: 322.1 GB, 322122547200 bytes

255 heads, 63 sectors/track, 39162 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: 0x00098804

Device Boot Start End Blocks Id System

/dev/sda1 * 1 64 512000 83 Linux Partition 1 does not end on cylinder boundary.

/dev/sda2 64 11749 93858816 8e Linux LVM

Disk /dev/mapper/vg_app2-lv_root: 53.7 GB, 53687091200 bytes

255 heads, 63 sectors/track, 6527 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

Disk /dev/mapper/vg_app2-lv_swap: 4160 MB, 4160749568 bytes

255 heads, 63 sectors/track, 505 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

Disk /de v/mapper/vg_app2-lv_home: 38.3 GB, 38260441088 bytes

255 heads, 63 sectors/track, 4651 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

根据提示信息可以判断出此系统的磁盘接口为SCSI，对应“sda”如果上面的红色字体是“hda”，那么此系统的磁盘接口为IDE对应“hda”所以我做一下操作：

#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 //“ 列出fdisk的帮助”

Command action

a toggle a bootable flag

b edit bsddisklabel

c toggle the dos compatibility flag

d delet

e 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):n //” 命令n用于添加新分区"

Command action

e extended

p primary partition (1-4)

p //" 选择创建主分区"此时，

Partition number (1-4):3 //fdisk会让你选择主分区的编号，如果已经有了主分区sda1，sda2，那么编号就选3，即要创建的该分区为sda3.

First cylinder (2611-3916, default 2611): //此时，fdisk又会让你选择该分区的开始值这个就是分区的Start 值（start cylinder）；这里最好直接按回车，

Using default value 2611

Last cylinder, +cylinders or +size{K,M,G} (2611-3916, default 3916): //此时，fdisk又会让你选择该分区的开始值这个就是分区的End 值这里最好直接按回车，

Using default value 3916

Command (m for help): w //w "保存所有并退出，分区划分完毕"

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.