LVM

[root@localhost ~]# lvdisplay 
  --- Logical volume ---
  LV Path                /dev/vg_root/lv_opt
  LV Name                lv_opt
  VG Name                vg_root
  LV UUID                24eBV3-UY8L-Yuel-2jKm-VlDC-sQMV-zQODY7
  LV Write Access        read/write
  LV Creation host, time localhost, 2018-11-15 14:32:30 +0800
  LV Status              available
  # open                 1
  LV Size                <15.50 GiB
  Current LE             3967
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:1
   
  --- Logical volume ---
  LV Path                /dev/vg_root/lv_tmp
  LV Name                lv_tmp
  VG Name                vg_root
  LV UUID                73xbdz-RV5j-ifd0-npSE-g2Ut-6P52-dHyhaZ
  LV Write Access        read/write
  LV Creation host, time localhost, 2018-11-15 14:32:32 +0800
  LV Status              available
  # open                 1
  LV Size                4.00 GiB
  Current LE             1024
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:2
   
  --- Logical volume ---
  LV Path                /dev/vg_root/lv_home
  LV Name                lv_home
  VG Name                vg_root
  LV UUID                7TzF7z-l4eL-LcZl-Dv6h-nfCC-3Ysd-HnhNqb
  LV Write Access        read/write
  LV Creation host, time localhost, 2018-11-15 14:32:34 +0800
  LV Status              available
  # open                 1
  LV Size                4.00 GiB
  Current LE             1024
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:3
   
  --- Logical volume ---
  LV Path                /dev/vg_root/lv_var
  LV Name                lv_var
  VG Name                vg_root
  LV UUID                fnck2V-dYdH-3h0R-qXai-Y1pz-YoDn-Xd1t0c
  LV Write Access        read/write
  LV Creation host, time localhost, 2018-11-15 14:32:35 +0800
  LV Status              available
  # open                 1
  LV Size                10.00 GiB
  Current LE             2560
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:4
   
  --- Logical volume ---
  LV Path                /dev/vg_root/lv_root
  LV Name                lv_root
  VG Name                vg_root
  LV UUID                leRKJl-a7xF-k5pH-uCcl-3fHa-m6Os-gVDW07
  LV Write Access        read/write
  LV Creation host, time localhost, 2018-11-15 14:32:37 +0800
  LV Status              available
  # open                 1
  LV Size                15.00 GiB
  Current LE             3840
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     8192
  Block device           253:0
   
[root@localhost ~]# vgdisplay 
  --- Volume group ---
  VG Name               vg_root
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  6
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                5
  Open LV               5
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               <48.50 GiB
  PE Size               4.00 MiB
  Total PE              12415
  Alloc PE / Size       12415 / <48.50 GiB
  Free  PE / Size       0 / 0   
  VG UUID               ntNYFD-dN4c-qC7A-aka0-M9MM-kq9w-gVuXHX
   
[root@localhost ~]# pvdisplay 
  --- Physical volume ---
  PV Name               /dev/sda3
  VG Name               vg_root
  PV Size               <48.50 GiB / not usable 3.00 MiB
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              12415
  Free PE               0
  Allocated PE          12415
  PV UUID               GgYEXm-CvC9-Bt4L-G8rR-qp0X-Faxo-e1cbnA
   
[root@localhost ~]# 

[root@localhost ~]# ll /dev/vg_root/
total 0
lrwxrwxrwx 1 root root 7 Nov 15 06:45 lv_home -> ../dm-3
lrwxrwxrwx 1 root root 7 Nov 15 06:45 lv_opt -> ../dm-1
lrwxrwxrwx 1 root root 7 Nov 15 06:45 lv_root -> ../dm-0
lrwxrwxrwx 1 root root 7 Nov 15 06:45 lv_tmp -> ../dm-2
lrwxrwxrwx 1 root root 7 Nov 15 06:45 lv_var -> ../dm-4
[root@localhost ~]#