Linux CENTOS7 LVM

嗯，我没有碰到这个链接-https: //themacwrangler.wordpress.com/2015/01/16/re-sizing-partitions-in-centos7/。很有帮助。

我也必须增加文件系统，而我没有。很好的学习。

万一将来内容不可用，请在上面的链接处复制页面的内容。

Re-sizing partitions in Centos7

By default in a CentOS7 install we get a couple of partitions created for the root user and one for home usually something like this:

# df -h
Filesystem                                   Size  Used Avail Use% Mounted on
/dev/mapper/centos-root                       50G  2.7G   48G   6% /
devtmpfs                                     239M     0  239M   0% /dev
tmpfs                                        246M     0  246M   0% /dev/shm
tmpfs                                        246M   29M  217M  12% /run
tmpfs                                        246M     0  246M   0% /sys/fs/cgroup
/dev/mapper/centos-home                       29G   33M   29G   1% /home
/dev/sda1                                    497M   96M  401M  20% /boot


Note that the root partition is 50Gb and the home partition is 29Gb

Often I find myself wanting or needing to remove the centos-home partition and expand the centos-root partition.

It is a pretty straight forward exercise, but one that I often forget the steps involved.

So here they are:
• First backup any data that might exist in /home so you can restore it later.
• Unmount the centos-home partition.

# umount /home/

• Next show the logical volumes.

# lvdisplay
  --- Logical volume ---
  LV Path                /dev/centos/swap
  LV Name                swap
  VG Name                centos
  LV UUID                azXfXa-YPiG-Bx9x-NfIO-eswN-iHVw-YsXpYe
  LV Write Access        read/write
  LV Creation host, time localhost, 2014-12-01 13:02:00 +1100
  LV Status              available
  # open                 2
  LV Size                1.03 GiB
  Current LE             264
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:1

  --- Logical volume ---
  LV Path                /dev/centos/home
  LV Name                home
  VG Name                centos
  LV UUID                LtYf7h-h1kx-p7OR-ZdN8-2Xo8-KXYT-uC2Roa
  LV Write Access        read/write
  LV Creation host, time localhost, 2014-12-01 13:02:01 +1100
  LV Status              available
  # open                 0
  LV Size                28.48 GiB
  Current LE             7290
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:2

  --- Logical volume ---
  LV Path                /dev/centos/root
  LV Name                root
  VG Name                centos
  LV UUID                DjnSO6-gsbN-g83Q-VhfC-u3Ft-8DqY-sPMx35
  LV Write Access        read/write
  LV Creation host, time localhost, 2014-12-01 13:02:03 +1100
  LV Status              available
  # open                 1
  LV Size                50.00 GiB
  Current LE             12800
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:0

•Now remove the logical volume for centos-home.

# lvremove /dev/centos/home
Do you really want to remove active logical volume home? [y/n]: y
Logical volume "home" successfully removed

•You should now have the free space available in VFree when you have a look using vgs.

# vgs
  VG                #PV #LV #SN Attr   VSize  VFree 
  centos              1   2   0 wz--n- 79.51g 28.48g

• Now resize the centos-root partition.

# lvresize -L +28.47GB /dev/mapper/centos-root 
  Rounding size to boundary between physical extents: 28.47 GiB
  Extending logical volume root to 78.47 GiB
  Logical volume root successfully resized


Note that I expanded the partition by slightly less than the available space, 28.47Gb instead of 28.48Gb, this is just to make sure you avoid hitting an insufficient free space error.
• Grow the partition to use all the free space

#xfs_growfs /dev/mapper/centos-root

• Confirm your new partition size.

# df -h
Filesystem                             Size  Used Avail Use% Mounted on
/dev/mapper/centos-root                 79G  2.7G   76G   4% /
devtmpfs                               239M     0  239M   0% /dev
tmpfs                                  246M     0  246M   0% /dev/shm
tmpfs                                  246M   29M  217M  12% /run
tmpfs                                  246M     0  246M   0% /sys/fs/cgroup
/dev/sda1                              497M   96M  401M  20% /boot