LVM--逻辑卷管理

[root@vm-centos7 ~]# fdisk /dev/sdb

Command (m for help): n      #按"n"键新建一个分区
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p      #出现菜单：e表示扩展分区，p表示主分区；这里首先创建主分区
Partition number (1-4, default 1): 1      #输入分区号，1表示第一个主分区
First sector (2048-41943039, default 2048):       #设置起始扇区，回车选择默认即可
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039): +1G      #设置末尾扇区，可通过+size{K,M,G}进行设置，这里设置为1G
Partition 1 of type Linux and of size 1 GiB is set

Command (m for help): n
Partition type:
   p   primary (1 primary, 0 extended, 3 free)
   e   extended
Select (default p): p
Partition number (2-4, default 2):       #创建第二个主分区
First sector (2099200-41943039, default 2099200):
Using default value 2099200
Last sector, +sectors or +size{K,M,G} (2099200-41943039, default 41943039):         #大小默认到最大值，即硬盘剩余大小
Using default value 41943039
Partition 2 of type Linux and of size 19 GiB is set

Command (m for help): t         #改变分区类型
Partition number (1,2, default 2):          #选择改变/dev/sdb2分区类型
Hex code (type L to list all codes): 8e         #调整为'Linux LVM'，所有类型列表可通过'l'查看
Changed type of partition 'Linux' to 'Linux LVM'

Command (m for help): p      #查看该硬盘下的所有分区

Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x1b95f623

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048     2099199     1048576   83  Linux
/dev/sdb2         2099200    41943039    19921920   8e  Linux LVM

Command (m for help): w      #保存并退出
The partition table has been altered!

[root@bomc-node20 ~]# df -Th
Filesystem           Type      Size  Used Avail Use% Mounted on
/dev/mapper/bel-root xfs        50G  3.7G   47G   8% /
/dev/sda1            xfs      1014M  154M  861M  16% /boot
/dev/mapper/bel-home xfs       410G  1.2G  409G   1% /home
[root@bomc-node20 opt]# lvdisplay
  --- Logical volume ---
  LV Path                /dev/bel/home
  LV Name                home
  VG Name                bel
  LV UUID                uyTIEv-IJHo-8a5D-dBx0-gzlT-wsUg-LUdkGm
  LV Write Access        read/write
  LV Creation host, time bomc-node20, 2018-05-04 13:47:39 +0800
  LV Status              available
  # open                 0
  LV Size                409.99 GiB
  Current LE             104957
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:2

[root@bomc-node20 ~]# df -Th
Filesystem           Type      Size  Used Avail Use% Mounted on
/dev/mapper/bel-root xfs        50G  4.8G   46G  10% /
/dev/sda1            xfs      1014M  154M  861M  16% /boot
/dev/mapper/bel-home xfs       200G  1.2G  199G   1% /home
[root@bomc-node20 ~]# lvdisplay
  --- Logical volume ---
  LV Path                /dev/bel/home
  LV Name                home
  VG Name                bel
  LV UUID                uyTIEv-IJHo-8a5D-dBx0-gzlT-wsUg-LUdkGm
  LV Write Access        read/write
  LV Creation host, time bomc-node20, 2018-05-04 13:47:39 +0800
  LV Status              available
  # open                 1
  LV Size                200.00 GiB
  Current LE             51200
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:2