虚拟机LVM扩容

1.先在Vmware上，把虚拟机硬盘做扩展，如果有快照存在，磁盘可能是不可编辑状态，先删除快照后再扩展。

2.现在打开虚拟机发现系统的磁盘空间已经扩了，但是硬盘分区可用空间没变，还是原来的30G

[root@localhost ~]# fdisk -l

Disk /dev/sda: 53.6 GB,  bytes
 heads,  sectors/track,  cylinders
Units = cylinders of  *  =  bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                                Linux
/dev/sda2                          +  8e  Linux LVM

3.使用 fdisk 新建分区，为lvm扩容做准备

[root@localhost ~]# fdisk /dev/sda

The number of cylinders for this disk is set to .
There is nothing wrong with that, but this is larger than ,
and could in certain setups cause problems with:
) software that runs at boot time (e.g., old versions of LILO)
) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/ FDISK)

Command (m for help): p

Disk /dev/sda: 53.6 GB,  bytes
 heads,  sectors/track,  cylinders
Units = cylinders of  *  =  bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                                Linux
/dev/sda2                          +  8e  Linux LVM

Command (m for help): n
Command action
   e   extended
   p   primary partition (-)
p
Partition number (-):
First cylinder (-, default ):
Using default value
Last cylinder or +size or +sizeM or +sizeK (-, default ):
Using default value 

Command (m for help): p

Disk /dev/sda: 53.6 GB,  bytes
 heads,  sectors/track,  cylinders
Units = cylinders of  *  =  bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                                Linux
/dev/sda2                          +  8e  Linux LVM
/dev/sda3                        +    Linux

调整磁盘分区/dev/sda3为LVM格式，防止重装系统是不能识别（感觉不调整格式也能用）

Command (m for help): t
Partition number (-):
Hex code (type L to list codes): 8e
Changed system type of partition  to 8e (Linux LVM)

Command (m for help): p

Disk /dev/sda: 53.6 GB,  bytes
 heads,  sectors/track,  cylinders
Units = cylinders of  *  =  bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *                                Linux
/dev/sda2                          +  8e  Linux LVM
/dev/sda3                        +  8e  Linux LVM

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 : Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
[root@localhost ~]# reboot

Broadcast message from root (pts/) (Wed Mar   :: ):

The system is going down for reboot NOW!

如果Re-reading the partition table 失败，可能分区还未识别，重启下再看。

4.建立 pv

[root@localhost ~]# pvcreate /dev/sda3
  Physical volume "/dev/sda3" successfully created

[root@localhost ~]# pvdisplay
  /dev/cdrom: open failed: No medium found
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               VolGroup00
  PV Size               29.90 GB / not usable 24.06 MB
  Allocatable           yes
  PE Size (KByte)
  Total PE
  Free PE
  Allocated PE
  PV UUID               o9H0fA-136u-HmOM-Ga3O-7R0i-VRAS-F1mNxZ

  --- NEW Physical volume ---
  PV Name               /dev/sda3
  VG Name
  PV Size               20.00 GB
  Allocatable           NO
  PE Size (KByte)
  Total PE
  Free PE
  Allocated PE
  PV UUID               Qib59l-uCF5-5fo0-6oqH-5Url-yuSA-Y6N0E0

5.扩展 vg

[root@localhost ~]# vgextend VolGroup00 /dev/sda3
  Volume group "VolGroup00" successfully extended

[root@localhost ~]# vgdisplay
  --- Volume group ---
  VG Name               VolGroup00
  System ID
  Format                lvm2
  Metadata Areas
  Metadata Sequence No
  VG Access             read/write
  VG Status             resizable
  MAX LV
  Cur LV
  Open LV
  Max PV
  Cur PV
  Act PV
  VG Size               49.88 GB
  PE Size               32.00 MB
  Total PE
  Alloc PE / Size        / 29.81 GB
  Free  PE / Size        / 20.06 GB
  VG UUID               8D7xnq-UPBK-LW2U-OCmc-Dl23-cpP1-qLLSHn

6.扩展lv

输入扩展单元，这里就是上面的Free PE 的大小。

[root@localhost ~]# lvextend -l + /dev/VolGroup00/LogVol00
  Extending logical volume LogVol00 to 47.94 GB
  Logical volume LogVol00 successfully resized

[root@localhost ~]# lvdisplay
  --- Logical volume ---
  LV Name                /dev/VolGroup00/LogVol00
  VG Name                VolGroup00
  LV UUID                QDtSfz-1SlB-xl3P-mRZp-H3dx-erAx-mAwrt2
  LV Write Access        read/write
  LV Status              available
  # open
  LV Size                47.94 GB
  Current LE
  Segments
  Allocation             inherit
  Read ahead sectors
  Block device           :

  --- Logical volume ---
  LV Name                /dev/VolGroup00/LogVol01
  VG Name                VolGroup00
  LV UUID                6nv9PJ-ho10-LPkA-0GBg-TBZt-z1Tf-F6S2Hu
  LV Write Access        read/write
  LV Status              available
  # open
  LV Size                1.94 GB
  Current LE
  Segments
  Allocation             inherit
  Read ahead sectors
  Block device           :

7.调整文件系统

[root@localhost ~]# resize2fs  /dev/mapper/VolGroup00-LogVol00
resize2fs 1.35 (-Feb-)
/dev/mapper/VolGroup00-LogVol00 is mounted; can't resize a mounted filesystem!

不能调整，使用 ext2online，我这边文件系统估计有点不对，所有会有些inode调整，忽略。

[root@localhost ~]# ext2online -v /dev/mapper/VolGroup00-LogVol00
ext2online v1.1.18 - // for EXT2FS .5b
new filesystem size
group  inode table has offset , not
group  inode table has offset , not
...
using  reserved group descriptor blocks
creating group  with  blocks (rsvd = , newgd =  )

cache direct hits: , indirect hits: , misses: 

注意，对于新的CentOS系统，可能是使用 xfs 格式的分区，需要用别的命令调整

[root@vt-c7 ~]# resize2fs /dev/mapper/centos-root
resize2fs 1.42. (-Dec-)
resize2fs: Bad magic number in super-block while trying to open /dev/mapper/centos-root
Couldn't find valid filesystem superblock.

检查是xfs格式并使用 xfs_growfs 命令来扩展

[root@vt-c7 ~]# cat /etc/fstab

#
# /etc/fstab
# Created by anaconda on Sun Apr  ::
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(), findfs(), mount() and/or blkid() for more info
#
/dev/mapper/centos-root /                       xfs     defaults
UUID=7c27bad9-295a--afc8-b1f721ba5a5d /boot                   xfs     defaults
/dev/mapper/centos-swap swap                    swap    defaults
[root@vt-c7 ~]# xfs_growfs /dev/mapper/centos-root
meta-data=/dev/mapper/centos-root isize=    agcount=, agsize= blks
         =                       sectsz=   attr=, projid32bit=
         =                       crc=        finobt= spinodes=
data     =                       bsize=   blocks=, imaxpct=
         =                       sunit=      swidth= blks
naming   =version               bsize=   ascii-ci= ftype=
log      =internal               bsize=   blocks=, version=
         =                       sectsz=   sunit= blks, lazy-count=
realtime =none                   extsz=   blocks=, rtextents=
data blocks changed from  to
[root@vt-c7 ~]#

8.打完收工

[root@localhost ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                       48G   27G   19G  % /
/dev/sda1              99M   13M   81M  % /boot
none                  772M       772M   % /dev/shm