今天本地的一臺伺服器根目錄佔用顯示為100%，查了一下，還是暫時先把home目錄下的一部分劃給/目錄

一、目錄佔用檢視

可以看到紅色部分的/目錄佔用為100%，而綠色部分的/home下還有865G，雖然不建議劃給/目錄，但還是想快速處理一下

二、備份

# mkdir /tmp/home
# cp -r /home/* /tmp/home

三、解除安裝

[root@aaa ]# umount /home
umount: /home: target is busy.
        (In some cases useful info about processes that use
         the device is found by lsof(8) or fuser(1))
 

解除安裝過程中出現了target is busy.
(In some cases useful info about processes that use
the device is found by lsof(8) or fuser(1))
那我們先解除佔用

[root@aaa ]# fuser  -mv -k  /home
                     USER        PID ACCESS COMMAND
/home:               root     kernel mount /home
                     git        1447 F.ce. gogs
 

再次解除安裝，查詢,就會發現已經解除安裝

[root@aaa ]# umount /home
[root@aaa ]# df -h

三、調整分割槽

按照以前的resize2fs方式來解除安裝分割槽,報了個錯

[root@aaa ]# resize2fs -p /dev/mapper/centos-home
e2fsck 1.42.9 (28-Dec-2013)
ext2fs_open2: Bad magic number in super-block
e2fsck: Superblock invalid, trying backup blocks...
e2fsck: Bad magic number in super-block while trying to open /dev/mapper/centos-home

The superblock could not be read or does not describe a correct ext2
filesystem.  If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
    e2fsck -b 8193 <device>
 

查了一下，檔案系統是xfs，不支援resize2fs，所以換一種方式

[root@aaa ]# cat /etc/fstab | grep centos-home
/dev/mapper/centos-home /home                   xfs     defaults        0 0

刪除home的邏輯卷

[root@aaa ]# lvremove /dev/mapper/centos-home
Do you really want to remove active logical volume centos/home? [y/n]: y
  Couldn't create temporary archive name.

還是有一些問題，是因為/為100%，滿了，所以需要刪一些東西才能釋放

刪除邏輯卷，重新調整/的大小,重新整理xfs，把剩下的劃分到/home中

[root@aaa ]# lvremove /dev/mapper/centos-home
  Logical volume "home" successfully removed
[root@aaa ]# lvextend -L 365G /dev/mapper/centos-root
  Size of logical volume centos/root changed from 50.00 GiB (12800 extents) to 365.00 GiB (93440 extents).
  Logical volume centos/root successfully resized.
[root@aaa ]# xfs_growfs /dev/mapper/centos-root
meta-data=/dev/mapper/centos-root isize=512    agcount=4, agsize=3276800 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        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=1
log      =internal               bsize=4096   blocks=6400, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 13107200 to 95682560

格式化分割槽，mount裝載,檢視

[root@aaa ]# lvcreate -l +100%free -n home centos
  Logical volume "home" created.
[root@ayc local]# mkfs.xfs /dev/mapper/centos-home
meta-data=/dev/mapper/centos-home isize=512    agcount=4, agsize=36033024 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=0, sparse=0
data     =                       bsize=4096   blocks=144132096, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=70377, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
mount /dev/mapper/centos-home /home
[root@aaa ]# mount /dev/mapper/centos-home /home
[root@aaa ]# df -h
Filesystem               Size  Used Avail Use% Mounted on
devtmpfs                  16G     0   16G   0% /dev
tmpfs                     16G   20K   16G   1% /dev/shm
tmpfs                     16G  795M   15G   5% /run
tmpfs                     16G     0   16G   0% /sys/fs/cgroup
/dev/mapper/centos-root  365G   50G  316G  14% /
/dev/sda1               1014M  205M  810M  21% /boot
tmpfs                    3.2G   12K  3.2G   1% /run/user/42
tmpfs                    3.2G     0  3.2G   0% /run/user/0
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/81f0e164187b58b5a6f86e14f573fd1b8971a7b013cd9a9b2f00b34ca4427c62/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/199e2290380e1820ff43ec0603010930cb45998392719fdc10ff4bfb7d2205a6/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/ca1b3a953378767f0fe4510617b3162abe2165f72aa3de20595ae860ea0d9466/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/3408eb97e4b4aac2956f6e67cec14334e11dfc5d677025a20d607a1f4ea883a3/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/4740e11acbe59cae037c4da113e0382e95b465b02cda081b0086102c9a28911a/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/7b331ea8c4ea05f2d7a55c59e8da35c23b3d8ed6adff3ec742a93f5cff388d33/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/cb138904b6c6b96a8112a0b41278dea5cae4b8e4e736052a961362248297f0d8/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/ba061d20b9d880a341fd2bfff961979ffbdec01ef0f081a13c15273c7f80efd4/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/25c4efcfe602b6e3e6c161cefec067bd5fbf456258fa5379eece87de21db606e/merged
overlay                  365G   50G  316G  14% /var/lib/docker/overlay2/f01ef666ef64b484e40b518a663a3e5ad9c51b6a175680135ba6e0e27d2e599e/merged
/dev/mapper/centos-home  550G   33M  550G   1% /home

恢復備份就ok啦

# cp -r /tmp/home* /home/