LVM详细操作

Posted 2022-05-09 一点点积累

LVM(Logical Volume Manager)

功能/命令	物理卷管理	卷管理	逻辑卷管理
扫描	pvscan	vgscan	lvscan
建立	pvcreate	vgcreate	lvcreate
显示	pvdisplay|pvs	vgdisplay|vgs	lvdisplay|lvs
删除	pvremove	vgremove	lvremove
扩容	-	vgextend	lvextend
缩小	-	vgreduce	lvreduce

创建LVM

• 物理卷初始化

$ pvcreate /dev/sdb1 /dev/sdc2
Physical volume "/dev/sdb1" successfully created.
Physical volume "/dev/sdc2" successfully created.

• 查看可用作物理卷的块设备

$lvmdiskscan
  /dev/centos/root [      46.99 GiB]
  /dev/sda1        [       1.00 GiB]
  /dev/centos/swap [       2.00 GiB]
  /dev/sda2        [     <49.00 GiB] LVM physical volume
  /dev/sdb1        [      50.00 GiB] LVM physical volume
  /dev/sdb2        [     <50.00 GiB]
  /dev/sdc1        [      20.00 GiB]
  /dev/sdc2        [     <30.00 GiB] LVM physical volume
  2 disks
  3 partitions
  0 LVM physical volume whole disks
  3 LVM physical volumes

• 创建卷组

$ vgcreate tmp /dev/sdb1
  Volume group "tmp" successfully created
$ vgs
  VG     #PV #LV #SN Attr   VSize   VFree
  centos   1   2   0 wz--n- <49.00g   4.00m
  data     2   1   0 wz--n-  49.99g <48.00g
  tmp      1   1   0 wz--n- <50.00g <49.00g

• 创建逻辑卷

$ lvcreate -n backup -L 1G tmp
  Logical volume "backup" created.
$ lvs
  LV     VG     Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root   centos -wi-ao---- 46.99g
  swap   centos -wi-ao----  2.00g
  data   data   -wi-ao---- <2.00g
  backup tmp    -wi-a-----  1.00g
  
$ lvcreate -n backup -l +100%VG

• 挂载逻辑卷

$ mkfs.xfs /dev/tmp/backup
$ mount /dev/tmp/backup /backup/
$ df -h /backup
文件系统                容量  已用  可用 已用% 挂载点
/dev/mapper/tmp-backup 1014M   33M  982M    4% /backup

扩容

卷组有空间

$ umount /backup  # 卸载磁盘
$ lvextend -L +1G --resizefs /dev/tmp/backup  # 扩容1G空间
$ lvs # 查看逻辑卷
  LV     VG     Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root   centos -wi-ao---- 46.99g
  swap   centos -wi-ao----  2.00g
  data   data   -wi-ao---- <2.00g
  backup tmp    -wi-a-----  2.00g
$ lvextend -l +100%FREE --resizefs /dev/tmp/backup  # 把卷组所有剩余空间扩展给backup逻辑卷
$ lvs
  LV     VG     Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root   centos -wi-ao----  46.99g
  swap   centos -wi-ao----   2.00g
  data   data   -wi-ao----  <2.00g
  backup tmp    -wi-a----- <50.00g

卷组没有空间

# 添加磁盘
$ umount /backup
$ pvcreate /dev/sdd 
$ vgextend tmp /dev/sdd
$ lvextend -L +1G /dev/tmp/backup
$ lvs

扩容根分区

$ pvcreate /dev/sdx
$ vgextend centos /dev/sdx
$ lvextend -l +100%FREE /dev/centos/root
$ xfs_growfs /dev/centos/root

更新硬盘

# /dev/sdx # 磁盘切换 /dev/sdz 替换/dev/sdx，sdz空间大于等于sdx。
$ pvcreate /dev/sdz
$ vgextend centos /dev/sdz
$ pvmove /dev/sdx /dev/sdz
$ vgreduce centos /dev/sdx