说明

需求：hone分区太大，根分区容量不够用，需要缩减home分区容量扩容给根分区

	根分区：50G

	home分区：1.7T

1 查看系统版本

[root@localhost home]# cat /etc/redhat-release 
CentOS Linux release 7.9.2009 (Core)

2 查看分区

使用df -h查看分区大小
[root@localhost home]# df -h
文件系统                 容量  已用  可用 已用% 挂载点
devtmpfs                  16G     0   16G    0% /dev
tmpfs                     16G  1.2M   16G    1% /dev/shm
tmpfs                     16G   69M   16G    1% /run
tmpfs                     16G     0   16G    0% /sys/fs/cgroup
/dev/mapper/centos-root   50G   28G   23G   56% /
/dev/sda2               1014M  169M  846M   17% /boot
/dev/sda1                200M   12M  189M    6% /boot/efi
/dev/sdb                 3.6T   39G  3.4T    2% /data
/dev/mapper/centos-home  1.7T   40M  1.7T    1% /home
tmpfs                    3.1G   32K  3.1G    1% /run/user/1000
tmpfs                    3.1G     0  3.1G    0% /run/user/0
tmpfs                    3.1G     0  3.1G    0% /run/user/26

3 查看文件分区类型

使用mount |grep root查看文件系统类型
[root@localhost home]# mount | grep root
/dev/mapper/centos-root on / type xfs (rw,relatime,seclabel,attr2,inode64,logbsize=256k,sunit=512,swidth=512,noquota)

分区类型说明
1、ext2/ext3/ext4文件系统的调整命令是resize2fs（增大和减小都支持）

lvextend -L 120G /dev/mapper/centos-home     //增大至120G
lvextend -L +20G /dev/mapper/centos-home     //增加20G
lvreduce -L 50G /dev/mapper/centos-home      //减小至50G
lvreduce -L -8G /dev/mapper/centos-home      //减小8G
resize2fs /dev/mapper/centos-home            //执行调整

2、xfs文件系统的调整命令是xfs_growfs（只支持增大）

lvextend -L 120G /dev/mapper/centos-home    //增大至120G
lvextend -L +20G /dev/mapper/centos-home    //增加20G
xfs_growfs /dev/mapper/centos-home          //执行调整

4 调整home分区

1 卸载home分区

卸载之前先对home分区进行备份

[root@localhost ]#cd home (切换到home目录下进行备份)
[root@localhost home]#tar -cvzf dell.tar.gz .
[root@localhost home]#mv dell.tar.gz /opt
[root@localhost ~]# umount /home

如提示home正忙请执行下面命令

[root@localhost home]# fuser -km /home/ 
/home:                4237m  4981cm  4991c  4992c  5035cm  5039c  5044c  5143cm  5148c  5151c  5180cm  5206m  5343c  5347cm  5349c  5351c  5363cm  5368cm  5373cm  5380cm  5401c  5407cm  5414c  5421c  5427c  5433c  5441c  5476cm  5479c  5480c  5482c  5483cm  5489cm  5492cm  5493c  5496cm  5500cm  5512cm  5513c  5515cm  5521cm  5523cm  5524cm  5526cm  5530cm  5546c  5574cm  5580c  5608c  5610c  5616c  5617cm  5624cm  5627cm  5630cm  5633cm  5665cm  5678cm  5711cm  5738c  5749cm  5770cm  5793c  5827c  5952cm  5970c  6078cm  6085c  6284cm  7336c 83790m
已杀死

2 查看分区大小

[root@localhost ~]# pvs
  PV         VG     Fmt  Attr PSize PFree
  /dev/sda3  centos lvm2 a--  1.74t 4.00m
[root@localhost ~]# vgs
  VG     #PV #LV #SN Attr   VSize VFree
  centos   1   3   0 wz--n- 1.74t 4.00m
[root@localhost ~]# lvs
  LV   VG     Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  home centos -wi-a-----   1.68t                                                    
  root centos -wi-ao----  50.00g                                                    
  swap centos -wi-ao---- <15.44g  

调整home分区缩减1T

[root@localhost ~]# lvreduce -L -1T /dev/centos/home 
  WARNING: Reducing active logical volume to 697.23 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 1.68 TiB (440636 extents) to 697.23 GiB (178492 extents).
  Logical volume centos/home successfully resized.

格式化分区

[root@localhost home]# mkfs.xfs /dev/mapper/centos-home -f
meta-data=/dev/mapper/centos-home isize=512    agcount=32, agsize=5711744 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0, sparse=0
data     =                       bsize=4096   blocks=182775808, imaxpct=25
         =                       sunit=64     swidth=64 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=89280, version=2
         =                       sectsz=512   sunit=64 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

挂载分区

[root@localhost home]# mount /dev/mapper/centos-home /home/

查看缩减后的容量

[root@localhost home]# df -h
文件系统                 容量  已用  可用 已用% 挂载点
devtmpfs                  16G     0   16G    0% /dev
tmpfs                     16G  1.2M   16G    1% /dev/shm
tmpfs                     16G   69M   16G    1% /run
tmpfs                     16G     0   16G    0% /sys/fs/cgroup
/dev/mapper/centos-root   50G   28G   23G   56% /
/dev/sda2               1014M  169M  846M   17% /boot
/dev/sda1                200M   12M  189M    6% /boot/efi
/dev/sdb                 3.6T   39G  3.4T    2% /data
tmpfs                    3.1G   12K  3.1G    1% /run/user/1000
tmpfs                    3.1G     0  3.1G    0% /run/user/0
tmpfs                    3.1G     0  3.1G    0% /run/user/26
tmpfs                    3.1G   12K  3.1G    1% /run/user/42
/dev/mapper/centos-home  697G   34M  697G    1% /home

查看vg

[root@localhost home]# 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                3
  Open LV               3
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               1.74 TiB
  PE Size               4.00 MiB
  Total PE              457389
  Alloc PE / Size       195244 / 762.67 GiB
  Free  PE / Size       262145 / 1.00 TiB
  VG UUID               9XQcUw-80iG-dGYH-Sp6q-cIA9-eWW1-at0qVg

给根分区扩容1T容量

[root@localhost home]# lvextend -L +1T /dev/centos/root 
  Size of logical volume centos/root changed from 50.00 GiB (12800 extents) to <1.05 TiB (274944 extents).
  Logical volume centos/root successfully resized.

执行xfs_growfs /dev/centos/root扩容

[root@localhost home]# xfs_growfs /dev/centos/root 
meta-data=/dev/mapper/centos-root isize=512    agcount=16, agsize=819200 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=13107200, imaxpct=25
         =                       sunit=64     swidth=64 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=6400, version=2
         =                       sectsz=512   sunit=64 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 13107200 to 281542656

最后查看扩容 是否成功

[root@localhost home]# df -h
文件系统                 容量  已用  可用 已用% 挂载点
devtmpfs                  16G     0   16G    0% /dev
tmpfs                     16G  1.2M   16G    1% /dev/shm
tmpfs                     16G   69M   16G    1% /run
tmpfs                     16G     0   16G    0% /sys/fs/cgroup
/dev/mapper/centos-root  1.1T   28G  1.1T    3% /
/dev/sda2               1014M  169M  846M   17% /boot
/dev/sda1                200M   12M  189M    6% /boot/efi
/dev/sdb                 3.6T   39G  3.4T    2% /data
tmpfs                    3.1G   12K  3.1G    1% /run/user/1000
tmpfs                    3.1G     0  3.1G    0% /run/user/0
tmpfs                    3.1G     0  3.1G    0% /run/user/26
tmpfs                    3.1G   12K  3.1G    1% /run/user/42
/dev/mapper/centos-home  697G   34M  697G    1% /home

[root@localhost home]# lvdisplay 
  --- Logical volume ---
  LV Path                /dev/centos/swap
  LV Name                swap
  VG Name                centos
  LV UUID                iGVNsJ-cSxQ-9hbw-x0fQ-QaOa-ndxj-EdHmPb
  LV Write Access        read/write
  LV Creation host, time localhost, 2023-04-18 19:46:27 +0800
  LV Status              available
  # open                 2
  LV Size                <15.44 GiB
  Current LE             3952
  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                ri6e0i-rAeq-G8pJ-F4Ro-wqKz-NzSZ-aj8LEU
  LV Write Access        read/write
  LV Creation host, time localhost, 2023-04-18 19:46:27 +0800
  LV Status              available
  # open                 1
  LV Size                697.23 GiB
  Current LE             178492
  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                No22n9-QO2V-M6vm-3QT0-c58r-r4Cf-aa6KjD
  LV Write Access        read/write
  LV Creation host, time localhost, 2023-04-18 19:46:28 +0800
  LV Status              available
  # open                 1
  LV Size                <1.05 TiB
  Current LE             274944
  Segments               2
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:0