linux系统虚拟机扩容

如果虚拟机内存在系统初始化时设置的比较小，后续内存不够用时，可以对虚拟机内存进行扩容。

1、关闭你的虚拟机系统

右键虚拟机，选择属性，选择硬盘，选择扩展。扩容时，不能有快照。且虚拟机关机。

扩大虚拟机的空间为"60G"(根据个人需要填写空间大小)。但是linux下面并不可见。

2、使用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

输出提示：

Disk /dev/sda: 64.4 GB, 64424509440 bytes

255 heads, 63 sectors/track, 7832 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: 0x00008d26

Device Boot Start End Blocks Id System

/dev/sda1 * 1 64 512000 83 Linux                     #此系统的磁盘接口为SCSI，对应“sda”，若此处为“hda”，则对应IDE磁盘接口

Partition 1 does not end on cylinder boundary.

/dev/sda2 64 2611 20458496 8e Linux LVM

Disk /dev/mapper/VolGroup-lv_root: 18.9 GB, 18865979392 bytes

255 heads, 63 sectors/track, 2293 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/VolGroup-lv_swap: 2080 MB, 2080374784 bytes

255 heads, 63 sectors/track, 252 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”，如果上面提示内容为“hda”，那么此系统的磁盘接口为IDE对应“hda”。所以此处进行如下操作：

# 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 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): 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 (2611-7832, 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} (2611-7832, default 7832): //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 7832

Command (m for help): 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.

3、我们的新建分区/dev/sda3，不是LVM的。所以，接下来使用fdisk将其改成LVM的。

# fdisk /dev/sda

Command (m for help): m

Command (m for help): t //改变分区系统id

Partition number (1-4): 3 //指定分区号

Hex code (type L to list codes): 8e //指定要改成的id号，8e代表LVM

Changed system type of partition 3 to 8e (Linux LVM)

Command (m for help): w

4、重启系统后，登陆系统。（一定要重启系统，否则无法扩充新分区）

# reboot //重启

5、格式化该新添加的分区

# fdisk -l

Disk /dev/sda: 64.4 GB, 64424509440 bytes

255 heads, 63 sectors/track, 7832 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: 0x00008d26

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 2611 20458496 8e Linux LVM

/dev/sda3 2611 7832 41939020 8e Linux LVM

Disk /dev/mapper/VolGroup-lv_root: 18.9 GB, 18865979392 bytes

255 heads, 63 sectors/track, 2293 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/VolGroup-lv_swap: 2080 MB, 2080374784 bytes

255 heads, 63 sectors/track, 252 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

你会发现多了一块分区

# mkfs -t ext3 /dev/sda3 //在硬盘分区“/dev/sda3”上创建“ext3”文件系统

mke2fs 1.41.12 (17-May-2010)

Filesystem label=

OS type: Linux

Block size=4096 (log=2)

Fragment size=4096 (log=2)

Stride=0 blocks, Stripe width=0 blocks

2621440 inodes, 10484755 blocks

524237 blocks (5.00%) reserved for the super user

First data block=0

Maximum filesystem blocks=4294967296

320 block groups

32768 blocks per group, 32768 fragments per group

8192 inodes per group

Superblock backups stored on blocks:

32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,

4096000, 7962624

Writing inode tables: done

Creating journal (32768 blocks): done

Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 23 mounts or

180 days, whichever comes first. Use tune2fs -c or -i to override.

此时我们就可以使用该新增分区啦：

6、扩充新分区

# lvs

LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert

lv_root VolGroup -wi-ao---- 17.57g

lv_swap VolGroup -wi-ao---- 1.94g

# pvcreate /dev/sda3

Physical volume "/dev/sda3" successfully created

# pvcreate /dev/sda3 //pvcreate指令用于将物理硬盘分区初始化为物理卷，以便被LVM使用。要创建物理卷必须首先对硬盘进行分区，并且将硬盘分区的类型设置为“8e”后，才能使用pvcreat指令将分区初始化为物理卷

Physical volume "/dev/sda3" successfully created

# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root 18G 1.7G 15G 10% /

tmpfs 1.9G 0 1.9G 0% /dev/shm

/dev/sda1 485M 32M 428M 7% /boot

# vgextend /dev/mapper/VolGroup-lv_root /dev/sda3 //其中是当前需要扩充的lvm组名，可以通过df -h查看） //vgextend指令用于动态的扩展卷组，它通过向卷组中添加物理卷来增加卷组的容量

Volume group name VolGroup/lv_root has invalid characters

# vgextend /dev/mapper/VolGroup /dev/sda3 //组名

Volume group "VolGroup" successfully extended

# vgdisplay //用于显示LNM卷组的元数据信息

--- Volume group ---

VG Name VolGroup

System ID

Format lvm2

Metadata Areas 2

Metadata Sequence No 4

VG Access read/write

VG Status resizable

MAX LV 0

Cur LV 2

Open LV 2

Max PV 0

Cur PV 2

Act PV 2

VG Size 59.50 GiB

PE Size 4.00 MiB

Total PE 15232

Alloc PE / Size 4994 / 19.51 GiB

Free PE / Size 10238 / 39.99 GiB

VG UUID Ecv3ml-86eg-LTsH-mALD-mLxW-v3Ao-GEqiFc

(主要查看Free PE / Size 10238 / 39.99 GiB，说明我们最多可以有39.99GB的扩充空间。我一般选择小于39.99GB)

# lvextend -L +39.09G /dev/VolGroup/lv_root /dev/sda3

这里如果失败，可以

# lvextend –L +39.09G /dev/mapper/VolGroup/lv_root /dev/sda3

Rounding size to boundary between physical extents: 39.09 GiB

Extending logical volume lv_root to 57.56 GiB

Logical volume lv_root successfully resized

后面的也需要相同的更改。

# e2fsck -f /dev/VolGroup/lv_root

e2fsck 1.41.12 (17-May-2010)

/dev/VolGroup/lv_root is mounted.

e2fsck: Cannot continue, aborting.

# resize2fs /dev/VolGroup/lv_root

或者 # xfs_growfs /dev/VolGroup/lv _root     //如果是ext4等文件系统可以通过命令resize2fs扩大。 xfs文件系统，需要使用命令xfs_growfs来完成文件系统扩大。

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/VolGroup/lv_root is mounted on /; on-line resizing required

old desc_blocks = 2, new_desc_blocks = 4

Performing an on-line resize of /dev/VolGroup/lv_root to 15089664 (4k) blocks.

The filesystem on /dev/VolGroup/lv_root is now 15089664 blocks long.

# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root 57G 1.7G 53G 3% /

tmpfs 1.9G 0 1.9G 0% /dev/shm

/dev/sda1 485M 32M 428M 7% /boot

可以看到，这个逻辑卷已经成功的扩容，根目录又可以装更多东西了!