Cenots7对lvm逻辑卷分区大小的调整

 

         (针对xfs和ext4不同文件系统)

      

1.支持的文件系统类型

 

特别注意的是:
resize2fs命令            针对的是ext2、ext3、ext4文件系统
xfs_growfs命令         针对的是xfs文件系统

1.1 分区增大、减小命令介绍

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

 

 

2.对分区进行增大

1) 将上面查到的空闲空间中的90G增减到/home分区上

[root@localhost ~]# lvextend -L +90G /dev/mapper/centos-home       //或者使用-l参数(跟PE数量),即lvextend -l +25500 /dev/mapper/centos-home

 Size of logical volume centos/home changed from 628.00 GiB (160768 extents) to 718.00 GiB (183808 extents).

  Logical volume centos/home successfully resized.

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

meta-data=/dev/mapper/centos-home isize=512    agcount=4, agsize=41156608 blks

       =                sectsz=512   attr=2, projid32bit=1

=                       crc=1        finobt=0 spinodes=0

 data        =                       bsize=4096   blocks=164626432, imaxpct=25

      =                 sunit=0      swidth=0 blks

naming   =version 2              bsize=4096   ascii-ci=0 ftype=1

log      =internal               bsize=4096   blocks=80384, version=2         =                  sectsz=512   sunit=0 blks, lazy-count=1

realtime =none                   extsz=4096   blocks=0, rtextents=0

  data blocks changed from 164626432 to 188219392

 

3 对分区进行减小

虽然xfs文件系统只支持增加,不支持减少。但并不是说在xfs系统文件下不能减小,只是减小后,需要重新格式化才能挂载上。这样原来的数据就丢失了!

 

系统安装好后,发现home分区过大,想从home分区中拿出100G给/分区

[root@localhost ~]# df –hT 

[root@localhost ~]# umount /home/ 

#注意要先备份一下/home目录的重要资料

umount /home 如果提示无法卸载,则是有进程占用/home,使用如下命令来终止占用进程:

 

[root@localhost ~]# fuser -m /home  #即使没有占用,也最好执行一下

 

[root@localhost ~]# lvreduce -L -100G /dev/mapper/centos-home

 

 WARNING: Reducing active logical volume to 618.00 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 718.00 GiB (183808 extents) to 618.00 GiB (158208 extents).

Logical volume centos/home successfully resized.

 

 

3.1.格式化 home 分区

[root@localhost ~]# mkfs.xfs /dev/mapper/centos-home –f

 

3.2.挂载分区

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

进行查看

[root@localhost ~]# df -hT   

 

上面在重新格式的时候,也可以将这个格式化为ext4格式。

[root@localhost ~]# mkfs.ext4 /dev/mapper/centos-home

[root@localhost ~]# cat /etc/fstab  //将home分区的开机挂载设置里的xfs改为ext4

3.3然后将上面从home分区拿出的100G放到/分区下

  

进行lvm 查看

 [root@localhost ~]# vgdisplay

 

[root@localhost ~]# lvextend -L +100G /dev/mapper/centos-root

Size of logical volume centos/root changed from 205.00 GiB (52480 extents) to 305.00 GiB (78080 extents).

Logical volume centos/root successfully resized.

 

[root@localhost ~]# xfs_growfs /dev/mapper/centos-root

meta-data=/dev/mapper/centos-root isize=256    agcount=5, agsize=13107200 blks

        =                sectsz=512   attr=2, projid32bit=1

        =               crc=0        finobt=0 spinodes=0

data     =                       bsize=4096   blocks=53739520, imaxpct=25

        =                   sunit=0      swidth=0 blks

naming   =version 2              bsize=4096   ascii-ci=0 ftype=0

log      =internal               bsize=4096   blocks=25600, version=2

        =          sectsz=512   sunit=0 blks, lazy-count=1

realtime =none                   extsz=4096   blocks=0, rtextents=0

data blocks changed from 53739520 to 79953920

 

进行查看

[root@localhost ~]# df -hT  

 

posted @ 2018-11-08 17:25  LWJ303  阅读(243)  评论(0编辑  收藏  举报
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