?????????
????home??500G
????root??50G
????root??????????
?????·????home???????仮??????root????
????# ????home??????С?200G?????300G???
????$ lvreduce -L 200G /dev/centos/home
????# ?????п???????root????
????$ lvextend -l +FREE /dev/centos/root
????# ???XFS????????????????????????
????$ xfs_growfs /dev/mapper/centos-root
???????
????situation
?????????????????? /dev/mapper/centos-root ?????????
$ df -h
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/centos-root   50G   50G   19M /
devtmpfs                  32G     0   32G   0% /dev
tmpfs                     32G     0   32G   0% /dev/shm
tmpfs                     32G  2.5G   29G   8% /run
tmpfs                     32G     0   32G   0% /sys/fs/cgroup
/dev/mapper/centos-home  476G   33M  476G   1% /home
/dev/sda1                497M  238M  259M  48% /boot
tmpfs                    6.3G     0  6.3G   0% /run/user/0
analyze
??????????????????????С?????50G?????????? home ???????????????????500G????
?????·???? centos-home ????????300G??? centos-root ??????
????operation
????1.???????????
$ lvdisplay
--- Logical volume ---
LV Path                /dev/centos/home
LV Name                home
VG Name                centos
LV UUID                1fAt1E-bQsa-1HXR-MCE2-5VZ1-xzBz-iI1SLv
LV Write Access        read/write
LV Creation host?? time localhost?? 2016-10-26 17:23:47 +0800
LV Status              available
# open                 0
LV Size                475.70 GiB
Current LE             121778
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                lD64zY-yc3Z-SZaB-dAjK-03YM-2gM8-pfj4oo
LV Write Access        read/write
LV Creation host?? time localhost?? 2016-10-26 17:23:48 +0800
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
????2.????/home???????
????# ??? /dev/centos/home ???? 300G ????
????# ???????? /dev/centos/home ???? 200G???
????$ lvreduce -L 200G /dev/centos/home
????WARNING: Reducing active logical volume to 200.00 GiB.
????THIS MAY DESTROY YOUR DATA (filesystem etc.)
????Do you really want to reduce centos/home? [y/n]: y
????Size of logical volume centos/home changed from 475.70 GiB (121778 extents) to 200.00 GiB (51200 extents).
????Logical volume centos/home successfully resized.
????3.????/root???????
????$ lvextend -l +FREE /dev/centos/root
????Size of logical volume centos/root changed from 50.06 GiB (12816 extents) to 325.76 GiB (83394 extents).
????Logical volume centos/root successfully resized.
????4.???XFS???????С
$ xfs_growfs /dev/mapper/centos-root
meta-data=/dev/mapper/centos-root isize=256    agcount=4?? agsize=3276800 blks
=                       sectsz=512   attr=2?? projid32bit=1
=                       crc=0        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=13107200?? imaxpct=25
=                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=0
log      =internal               bsize=4096   blocks=6400?? version=2
=                       sectsz=512   sunit=0 blks?? lazy-count=1
realtime =none                   extsz=4096   blocks=0?? rtextents=0
data blocks changed from 13107200 to 85395456
???????