CentOS6.5 虚拟机 磁盘扩容

1. 关闭虚拟机

2. 编辑虚拟机设置：增加硬盘的置备大小，或者添加新的硬盘

3. 启动虚拟机，查看可用磁盘大小 ：

# df -Th

Filesystem Type Size Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root ext4 18G 1.8G 15G 11% /

tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm

/dev/sda1 ext4 485M 39M 421M 9% /boot

　　此时为未扩容前：20G，目标扩容挂载在根目录的/dev/mapper/VolGroup-lv_root 逻辑卷。

 

4. 查看分区信息：

# fdisk -l

Disk /dev/sda: 42.9 GB, 42949672960 bytes

255 heads, 63 sectors/track, 5221 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: 0x000244d1

 

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

 

Disk /dev/mapper/VolGroup-lv_root: 18.8 GB, 18798870528 bytes

255 heads, 63 sectors/track, 2285 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: 2147 MB, 2147483648 bytes

255 heads, 63 sectors/track, 261 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

　　磁盘/dev/sda已有两个分区sda1、sda2。

 

5. 接下来要新建分区sda3：

# fdisk /dev/sda

Command (m for help): n

Command action

e extended

p primary partition (1-4)

p

Partition number (1-4): 3

First cylinder (2611-5221, default 2611): 回车默认

Using default value 2611

Last cylinder, +cylinders or +size{K,M,G} (2611-5221, default 5221): 回车默认

Using default value 5221

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.

 

6. 尝试partprobe命令更新分区，若失败，则reboot。

 

7. 创建pv(物理卷)：

# pvcreate /dev/sda3

dev_is_mpath: failed to get device for 8:3

Physical volume "/dev/sda3" successfully created

 

8. 查看vg（卷组），确认需要扩展的vg：

# vgdisplay

--- Volume group ---

VG Name VolGroup

System ID

Format lvm2

Metadata Areas 1

Metadata Sequence No 3

VG Access read/write

VG Status resizable

MAX LV 0

Cur LV 2

Open LV 2

Max PV 0

Cur PV 1

Act PV 1

VG Size 19.51 GiB

PE Size 4.00 MiB

Total PE 4994

Alloc PE / Size 4994 / 19.51 GiB

Free PE / Size 0 / 0

VG UUID MT0rRr-UWcY-ZYQ5-oR0C-q96r-NcbG-ufKJnz

此时未分配的空间为0

 

9. 扩展vg（卷组）：

# vgextend VolGroup /dev/sda3

Volume group "VolGroup" successfully extended

　　再次查看vg：

# vgdisplay

--- 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 39.50 GiB

PE Size 4.00 MiB

Total PE 10112

Alloc PE / Size 4994 / 19.51 GiB

Free PE / Size 5118 / 19.99 GiB

VG UUID MT0rRr-UWcY-ZYQ5-oR0C-q96r-NcbG-ufKJnz

 

10. 扩展lv（逻辑卷）：

# lvextend /dev/mapper/VolGroup-lv_root -L +19.99G

Rounding size to boundary between physical extents: 19.99 GiB

Extending logical volume lv_root to 37.50 GiB

Logical volume lv_root successfully resized

 

11. 格式化文件系统：

# resize2fs /dev/mapper/VolGroup-lv_root

resize2fs 1.41.12 (17-May-2010)

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

old desc_blocks = 2, new_desc_blocks = 3

Performing an on-line resize of /dev/mapper/VolGroup-lv_root to 9830400 (4k) blocks.

The filesystem on /dev/mapper/VolGroup-lv_root is now 9830400 blocks long.

　　之前df -Th 查看/dev/mapper/VolGroup-lv_root的Type为ext4，所以使用resize2fs；如果文件类型是 xfs ，则使用如下命令格式化：

# xfs_growfs /dev/mapper/VolGroup-lv_root

 

12. df -Th 确认扩容成功

# df -Th

Filesystem Type Size Used Avail Use% Mounted on

/dev/mapper/VolGroup-lv_root ext4 37G 1.8G 34G 6% /

tmpfs tmpfs 3.9G 0 3.9G 0% /dev/shm

/dev/sda1 ext4 485M 39M 421M 9% /boot

 

参考：

https://www.jianshu.com/p/94ab4588d77c