Centos7系统根分区空间小,home空间大。怎么删除home分区增加到分区

红太狼 2022-11-08 14:17 494阅读 0赞

## 前言 ##

新的centos系统的时候，默认分区（如果你的磁盘比较大），他默认会把/根分区分50G，而把其他空间放到/home分区下面，这样的话你的根分区容量就太小了，很容易满，就造成了Centos7系统根分区空间小,/home空间大，那么怎么样把这个/home给他删除扩容到/根分区呢？

## 解决步骤 ##

1.  查看分区

[root@his ~]# df -Th
    文件系统                类型      容量  已用  可用 已用% 挂载点
    devtmpfs                devtmpfs  4.2G     0  4.2G    0% /dev
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /dev/shm
    tmpfs                   tmpfs     4.2G   21M  4.2G    1% /run
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /sys/fs/cgroup
    /dev/mapper/centos-root xfs        50G   46G  4.2G   92% /
    /dev/sda1               xfs      1014M  150M  865M   15% /boot
    /dev/mapper/centos-home xfs       745G  2.3G  743G    1% /home
    tmpfs                   tmpfs     860M     0  860M    0% /run/user/0
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/bedd245e5d20bdadbd56af18b9cd0c41e66963ccb0d072f37d1830119e3be190/merged
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/d28d7d3345cf9cc67bd1da0bd9fc0a9eade720865b8b9f4bd01ba41239ce2d06/merged
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/fa39b1dd91ee787c522977f6cf9366a836eea7800dbd062f42082d1e2ad126da/merged

2.分区表修改

删掉home分区或者注释掉

vi /etc/fstab
    
    #
    # /etc/fstab
    # Created by anaconda on Mon Mar 8 09:39:01 2021
    #
    # Accessible filesystems, by reference, are maintained under '/dev/disk'
    # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
    #
    /dev/mapper/centos-root /                       xfs     defaults        0 0
    UUID=9b74bde6-6d0e-4b32-a1af-ac1e4ea927e9 /boot                   xfs     defaults        0 0
    #/dev/mapper/centos-home /home xfs defaults 0 0
    /dev/mapper/centos-swap swap                    swap    defaults        0 0

3.卸载掉/home分区,然后查看/home分区已经没有了（如果有数据，需要备份，我这里没有数据）

[root@his ~]# umount /home
    [root@his ~]# df -Th
    文件系统                类型      容量  已用  可用 已用% 挂载点
    devtmpfs                devtmpfs  4.2G     0  4.2G    0% /dev
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /dev/shm
    tmpfs                   tmpfs     4.2G   21M  4.2G    1% /run
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /sys/fs/cgroup
    /dev/mapper/centos-root xfs        50G   46G  4.2G   92% /
    /dev/sda1               xfs      1014M  150M  865M   15% /boot
    tmpfs                   tmpfs     860M     0  860M    0% /run/user/0
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/bedd245e5d20bdadbd56af18b9cd0c41e66963ccb0d072f37d1830119e3be190/merged
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/d28d7d3345cf9cc67bd1da0bd9fc0a9eade720865b8b9f4bd01ba41239ce2d06/merged
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/fa39b1dd91ee787c522977f6cf9366a836eea7800dbd062f42082d1e2ad126da/merged

4.查看有哪些lv逻辑分区

[root@his ~]# lvscan
      ACTIVE            '/dev/centos/swap' [4.31 GiB] inherit
      ACTIVE            '/dev/centos/home' [<744.68 GiB] inherit
      ACTIVE            '/dev/centos/root' [50.00 GiB] inherit

5.移除/home的lv分区

lvremove /dev/mapper/centos-home
    #再看一下
    [root@his ~]# lvscan
      ACTIVE            '/dev/centos/swap' [4.31 GiB] inherit
      ACTIVE            '/dev/centos/root' [50.00 GiB] inherit

6.查看一下vg的设置

[root@his ~]# vgdisplay
      --- Volume group ---
      VG Name               centos
      System ID             
      Format                lvm2
      Metadata Areas        1
      Metadata Sequence No  5
      VG Access             read/write
      VG Status             resizable
      MAX LV                0
      Cur LV                2
      Open LV               2
      Max PV                0
      Cur PV                1
      Act PV                1
      VG Size               <799.00 GiB
      PE Size               4.00 MiB
      Total PE              204543
      Alloc PE / Size       13904 / 54.31 GiB
      Free  PE / Size       190639 / 744.68 GiB
      VG UUID               poiSdH-FBDX-L8Qb-031s-cHw6-AVy7-qh8HPX

可以看到空闲出来的

Free  PE / Size       190639 / 744.68 GiB

7.把空闲出来的全部扩展到根路径下

lvextend -l +100%free /dev/mapper/centos-root
    #如果部分用大L，全部用小l
    lvextend -L +1T /dev/mapper/centos-root
    lvextend -L +200G /dev/mapper/centos-root

[root@his ~]# lvextend -l +100%free /dev/mapper/centos-root
      Size of logical volume centos/root changed from 50.00 GiB (12800 extents) to 794.68 GiB (203439 extents).
      Logical volume centos/root successfully resized.

扩容完成之后，他的容量还没有增加，我们需要刷新一下,需要执行一个命令

[root@his ~]# df -Th
    文件系统                类型      容量  已用  可用 已用% 挂载点
    devtmpfs                devtmpfs  4.2G     0  4.2G    0% /dev
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /dev/shm
    tmpfs                   tmpfs     4.2G   21M  4.2G    1% /run
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /sys/fs/cgroup
    /dev/mapper/centos-root xfs        50G   46G  4.2G   92% /
    /dev/sda1               xfs      1014M  150M  865M   15% /boot
    tmpfs                   tmpfs     860M     0  860M    0% /run/user/0
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/bedd245e5d20bdadbd56af18b9cd0c41e66963ccb0d072f37d1830119e3be190/merged
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/d28d7d3345cf9cc67bd1da0bd9fc0a9eade720865b8b9f4bd01ba41239ce2d06/merged
    overlay                 overlay    50G   46G  4.2G   92% /var/lib/docker/overlay2/fa39b1dd91ee787c522977f6cf9366a836eea7800dbd062f42082d1e2ad126da/merged

8.刷新,扩大/文件系统,时间长短看你的磁盘容量大小

#如果是centos7是xfs_growfs，如果是centos6是resize2fs
    xfs_growfs /dev/mapper/centos-root

[root@his ~]# xfs_growfs /dev/mapper/centos-root
    meta-data=/dev/mapper/centos-root isize=512    agcount=4, agsize=3276800 blks
             =                       sectsz=512   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=512   sunit=0 blks, lazy-count=1
    realtime =none                   extsz=4096   blocks=0, rtextents=0
    data blocks changed from 13107200 to 208321536

9.最后查看

[root@his ~]# df -Th
    文件系统                类型      容量  已用  可用 已用% 挂载点
    devtmpfs                devtmpfs  4.2G     0  4.2G    0% /dev
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /dev/shm
    tmpfs                   tmpfs     4.2G   21M  4.2G    1% /run
    tmpfs                   tmpfs     4.2G     0  4.2G    0% /sys/fs/cgroup
    /dev/mapper/centos-root xfs       795G   46G  749G    6% /
    /dev/sda1               xfs      1014M  150M  865M   15% /boot
    tmpfs                   tmpfs     860M     0  860M    0% /run/user/0
    overlay                 overlay   795G   46G  749G    6% /var/lib/docker/overlay2/bedd245e5d20bdadbd56af18b9cd0c41e66963ccb0d072f37d1830119e3be190/merged
    overlay                 overlay   795G   46G  749G    6% /var/lib/docker/overlay2/d28d7d3345cf9cc67bd1da0bd9fc0a9eade720865b8b9f4bd01ba41239ce2d06/merged
    overlay                 overlay   795G   46G  749G    6% /var/lib/docker/overlay2/fa39b1dd91ee787c522977f6cf9366a836eea7800dbd062f42082d1e2ad126da/merged