39、逻辑卷管理器LVM

yum install lvm2 -

[16:22:14root@LGW-Linux-7data]#pvcreate /dev/sdb{1,2}
  Device /dev/sdb2 not found.
  Can't open /dev/sdb1 exclusively.  Mounted filesystem?
  Can't open /dev/sdb1 exclusively.  Mounted filesystem?

[16:22:14root@LGW-Linux-7data]#pvcreate /dev/sdb{1,2}
  Device /dev/sdb2 not found.
  Can't open /dev/sdb1 exclusively.  Mounted filesystem?
  Can't open /dev/sdb1 exclusively.  Mounted filesystem?

[16:28:17root@LGW-Linux-7data]#fdisk -l /dev/sdb

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: 0x000162d4

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048     2099199     1048576   8e  Linux LVM
/dev/sdb2         2099200     6293503     2097152   8e  Linux LVM
[16:28:26root@LGW-Linux-7data]#pvcreate /dev/sdb{1,2}
  Physical volume "/dev/sdb1" successfully created.
  Physical volume "/dev/sdb2" successfully created.
[16:28:41root@LGW-Linux-7data]#pvs
  PV         VG Fmt  Attr PSize PFree
  /dev/sdb1     lvm2 ---  1.00g 1.00g
  /dev/sdb2     lvm2 ---  2.00g 2.00g
[16:29:14root@LGW-Linux-7data]#pvdisplay 
  "/dev/sdb2" is a new physical volume of "2.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb2
  VG Name               
  PV Size               2.00 GiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               Q0XJT0-QBJH-3Ss0-jwes-O3Ty-kd7l-NaqP1M
   
  "/dev/sdb1" is a new physical volume of "1.00 GiB"
  --- NEW Physical volume ---
  PV Name               /dev/sdb1
  VG Name               
  PV Size               1.00 GiB
  Allocatable           NO
  PE Size               0   
  Total PE              0
  Free PE               0
  Allocated PE          0
  PV UUID               9sOiQv-krRb-Hicq-dz4g-eOC2-5UzX-szybF7

pvmove /dev/sdb2

vgreduce vg0 /dev/sdb2

pvremove /dev/sdb2

lvcreate -L 100M -s -n lvs-snapshot -p r /dev/vg0/lvs1
s 快照  n命名  -L 大小空间

umount /dev/vg0/lvs*
lvconvert --merge /dev/vg0/lvs-snapshot