虚拟机中CentOS 6.5 添加扩展分区

此扩展方法要求支持LVM

1、更改虚拟机配置

虚拟机->设置->硬盘->扩展磁盘容量

fdisk -l 查看，发现硬盘空间变大了

[root@thj Desktop]# fdisk -l

Disk /dev/sda: 42.9 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: 0x000812b5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                                Linux
Partition  does not end on cylinder boundary.
/dev/sda2                             8e  Linux LVM

Disk /dev/mapper/vg_thj-lv_root: 18.9 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: 0x00000000

Disk /dev/mapper/vg_thj-lv_swap:  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

2、创建分区

[root@thj Desktop]# 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): p    #查看分区表信息

Disk /dev/sda: 42.9 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: 0x000812b5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                                Linux
Partition  does not end on cylinder boundary.
/dev/sda2                             8e  Linux LVM

Command (m for help): n   #创建新的分区
Command action
   e   extended
   p   primary partition (-)
p        #创建为主分区
Partition number (-):
First cylinder (-, default ):
Using default value                          #默认就好
Last cylinder, +cylinders or +size{K,M,G} (-, default ):
Using default value             #默认就好

Command (m for help): p   #查看分区表

Disk /dev/sda: 42.9 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: 0x000812b5

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                                Linux
Partition  does not end on cylinder boundary.
/dev/sda2                             8e  Linux LVM
/dev/sda3                        +    Linux

Command (m for help): w  #保存
The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error : 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() or kpartx()
Syncing disks.

设置完后，reboot重启系统

3、格式化分区

[root@thj Desktop]# mkfs.ext3 /dev/sda3
mke2fs 1.41. (-May-)
Filesystem label=
OS type: Linux
Block size= (log=)
Fragment size= (log=)
Stride= blocks, Stripe width= blocks
 inodes,  blocks
 blocks (5.00%) reserved for the super user
First data block=
Maximum filesystem blocks=
 block groups
 blocks per group,  fragments per group
 inodes per group
Superblock backups stored on blocks:
    , , , , , , , , , 

Writing inode tables: done
Creating journal ( blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every  mounts or
 days, whichever comes first.  Use tune2fs -c or -i to override.

4、加入LVM，并挂载到根目录下

• vgs 查看卷组情况

[root@thj Desktop]# vgs
  VG     #PV #LV #SN Attr   VSize  VFree
  vg_thj          wz--n- .51g                //有一个vg_thj卷组（此处系统不同会有所不同）

• 创建物理卷（LVM分区），并将物理卷加入vg_thj组里

[root@thj Desktop]# lvm
lvm> pvcreate /dev/sda3      //创建一个LVM硬分区
  Physical volume "/dev/sda3" successfully created
lvm> vgextend vg_thj /dev/sda3    //加入与根目录同一个LVM组
  Volume group "vg_thj" successfully extended

• 查看 lv path

[root@thj Desktop]# lvdisplay
  --- Logical volume ---
  LV Path                /dev/vg_thj/lv_root      //root对应的lv path
  LV Name                lv_root
  VG Name                vg_thj
  LV UUID                FMlzw9-r8dt-2Oa1-mS0W-brnn-YsDm-g3ld5S
  LV Write Access        read/write
  LV Creation host, time thj.localthj, -- :: +
  LV Status              available
  # open
  LV Size                17.57 GiB
  Current LE
  Segments
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to
  Block device           :

  --- Logical volume ---
  LV Path                /dev/vg_thj/lv_swap
  LV Name                lv_swap
  VG Name                vg_thj
  LV UUID                lLgahm-QUMF-XHiN-jZJc-F5ve-YycI-FmEVdr
  LV Write Access        read/write
  LV Creation host, time thj.localthj, -- :: +
  LV Status              available
  # open
  LV Size                1.94 GiB
  Current LE
  Segments
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to
  Block device           :

• 扩展 lv path

[root@thj Desktop]# lvextend -L +.99G /dev/vg_thj/lv_root
  Rounding size to boundary between physical extents: 19.99 GiB.
  Size of logical volume vg_thj/lv_root changed from 17.57 GiB ( extents) to 37.56 GiB ( extents).
  Logical volume lv_root successfully resized.

• 重置主分区大小

[root@thj Desktop]# resize2fs /dev/vg_thj/lv_root
resize2fs 1.41. (-May-)
Filesystem at /dev/vg_thj/lv_root is mounted on /; on-line resizing required
old desc_blocks = , new_desc_blocks =
Performing an on-line resize of /dev/vg_thj/lv_root to  (4k) blocks.
The filesystem on /dev/vg_thj/lv_root is now  blocks long.

有时报错：

[root@thj Desktop]# lvextend -L +19G /dev/vg_thj/lv_root
  Couldn't find device with uuid N0xspW-ZOct-v7pH-GHRN-G1Ck-0CnJ-ghqEKZ.
  Cannot change VG vg_thj while PVs are missing.
  Consider vgreduce --removemissing.
  Cannot process volume group vg_thj

参考  https://blog.51cto.com/yl497103815/1180426

• 查看扩展后的文件系统

[root@thj Desktop]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_thj-lv_root
                       37G   12G   24G  % /
tmpfs                 491M  228K  491M   % /dev/shm
/dev/sda1             477M   36M  417M   % /boot