Linux lvm逻辑卷创建管理删除
①PV(Physical Volume) 物理卷
②PE(Physical Extend) 物理拓展
③VG(Volume Group) 卷组
④LV(Logical Volume) 逻辑卷
工作原理:
(1)物理磁盘被格式化为PV,空间被划分为一个个的PE
(2)不同的PV加入到同一个VG中,不同PV的PE全部进入到了VG的PE池内
(3)LV基于PE创建,大小为PE的整数倍,组成LV的PE可能来自不同的物理磁盘
(4)LV现在就直接可以格式化后挂载使用了
(5)LV的扩充缩减实际上就是增加或减少组成该LV的PE数量,其过程不会丢失原始数据
前期准备:
使用空闲磁盘/dev/sdb和/dev/sdc,更改硬盘格式为8e
[[email protected] ~]# fdisk /dev/sdb
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): p
Disk /dev/sdb: 3221 MB, 3221225472 bytes
255 heads, 63 sectors/track, 391 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x611c6c72
Device Boot Start End Blocks Id System
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-391, default 1): 1
Last cylinder, +cylinders or +size{K,M,G} (1-391, default 391): +1G
Command (m for help): p
Disk /dev/sdb: 3221 MB, 3221225472 bytes
255 heads, 63 sectors/track, 391 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x611c6c72
Device Boot Start End Blocks Id System
/dev/sdb1 1 132 1060258+ 83 Linux
Command (m for help): t 更换硬盘格式
Selected partition 1
Hex code (type L to list codes): 8e 改为8e
Changed system type of partition 1 to 8e (Linux LVM)
Command (m for help): p
Disk /dev/sdb: 3221 MB, 3221225472 bytes
255 heads, 63 sectors/track, 391 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x611c6c72
Device Boot Start End Blocks Id System
/dev/sdb1 1 132 1060258+ 8e Linux LVM
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
-------------------------------------------------------分隔符-------------------------------------------------------
[[email protected] ~]# ls /dev/sd* 查看刚创建的分区
/dev/sda /dev/sda1 /dev/sda2 /dev/sdb /dev/sdb1 /dev/sdc
[[email protected] ~]# partprobe /dev/sdb 如果没有的话使用该命令更新分区表
LVM命令:
创建========================================
pvcreate /dev/sdb1 /dev/sdc1 创建pv
pvs 查看pv
pvdisplay 查看pv详细信息
vgcreate vg0 /dev/sdb1 /dev/sdc1 创建vg0
vgs 查看vg
vgdisplay 查看vg详细信息
lvcreate -n lv0 -L 200M vg0 创建lv0 大小为200M,从vg0调容量
lvs 查看lv
lvdiaplay 查看lv详细信息
mkfd.ext4 /dev/vg0/lv0 挂载lvm卷
扩展vg======================================
vgextend vg0 /dev/sdc2 /dev/sdc2创建为pv添加到vg0
vgscan 查看vg
缩减vg======================================
pvscan 查看哪些pv没被使用
vgreduce vg0 /dev/sdc2 缩减sdc2
vgdisplay 查看vg详细信息
扩展lv(支持在线扩展,不用卸载)=================
lvextend -L +100M /dev/vg0/lv0 扩展100M给lv0
lvs 查看lv
resize2fs /dev/vg0/lv0 扩展文件系统容量
df -h 查看挂载容量
缩减lv(不支持在线扩展,必须卸载)================
umount /dev/vg0/lv0 卸载lv0
e2fsck -f /dev/vg0/lv0 强制检查文件系统
resize2fs /dev/vg0/lv0 150M 缩减到150M
lvreduce -L 150M /dev/vg0/lv0 缩减到150M
lvs 查看lv
mount /dev/vg0/lv0 /lvmtest 重新挂载lv0
删除:
1.卸载:umount
删除顺序:
1.删lv: lvremove lv完整路径
2.删vg:vgremove vg名
3.删PV:pvremove 设备完整路径 去硬盘