Vmware私有云虚拟机（CentOS 6.5 OS）之根分区扩容

注：适用于未使用lvm管理的分区，目前仅在CentOS 6.5 上操作，其他系统尚未测试，请谨慎操作

一、查看当前分区状况

[root@disk-test ~]# df -h

Filesystem      Size  Used Avail Use% Mounted on

/dev/sda3        26G  2.3G   22G  10% /

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

/dev/sda1       194M   34M  151M  19% /boot

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二、控制台调增虚拟机磁盘

关闭系统，在控制台调增虚拟机磁盘大小为50G，重启系统

[root@disk-test ~]# fdisk -l

Disk /dev/sda: 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: 0x000cea7e

Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *           1          26      204800   83  Linux

Partition 1 does not end on cylinder boundary.

/dev/sda2              26         548     4194304   82  Linux swap / Solaris

Partition 2 does not end on cylinder boundary.

/dev/sda3             548        3917    27057152   83  Linux                          #注意这里起始cylinder 是548，起始cylinder 绝对不可以改，这样会破坏原分区的数据。

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三、扩展根分区/dev/sda

[root@sjsa-disk-test ~]# 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

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): p

Disk /dev/sda: 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: 0x000cea7e

Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *           1          26      204800   83  Linux

Partition 1 does not end on cylinder boundary.

/dev/sda2              26         548     4194304   82  Linux swap / Solaris

Partition 2 does not end on cylinder boundary.

/dev/sda3             548        3917    27057152   83  Linux

Command (m for help): d

Partition number (1-4): 3                                               #根/分区是多少就输入几，这里是/dev/sda3

Command (m for help): p

Disk /dev/sda: 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: 0x000cea7e

Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *           1          26      204800   83  Linux

Partition 1 does not end on cylinder boundary.

/dev/sda2              26         548     4194304   82  Linux swap / Solaris

Partition 2 does not end on cylinder boundary.

Command (m for help): n

Command action

e   extended

p   primary partition (1-4)

p

Partition number (1-4): 3                                             #之前是多少，这里还输入多少

First cylinder (548-6527, default 548):

Using default value 548

Last cylinder, +cylinders or +size{K,M,G} (548-6527, default 6527):                         #由之前3917，扩为6527

Using default value 6527

Command (m for help): p

Disk /dev/sda: 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: 0x000cea7e

Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *           1          26      204800   83  Linux

Partition 1 does not end on cylinder boundary.

/dev/sda2              26         548     4194304   82  Linux swap / Solaris

Partition 2 does not end on cylinder boundary.

/dev/sda3             548        6527    48027999+  83  Linux                                      #变成了6527

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.

三、重启系统，完成根分区扩充

执行如下命令，重启系统

[root@sjsa-disk-test ~]# reboot

执行如下命令，完成根分区扩充

[root@sjsa-disk-test ~]# resize2fs /dev/sda3

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/sda3 is mounted on /; on-line resizing required

old desc_blocks = 2, new_desc_blocks = 3

Performing an on-line resize of /dev/sda3 to 12006999 (4k) blocks.

The filesystem on /dev/sda3 is now 12006999 blocks long.

四、验证

查看当前磁盘状态

[root@sjsa-disk-test ~]# df -h

Filesystem      Size  Used Avail Use% Mounted on

/dev/sda3        46G  2.3G   41G   6% /

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

/dev/sda1       194M   34M  151M  19% /boot

如上，完成对根分区的扩充