Linux Basic--LVM Management

Lvm:logical Volume Manager (logical Volume management)

Many Linux users encounter the dilemma of installing the operating system: how to accurately evaluate and allocate the capacity of each hard disk partition, if the initial evaluation is not accurate, once the system partition is not enough, you may have to back up, delete the relevant data, or even be forced to re-plan the partition and reinstall the operating system to meet the needs of the application system.

LVM is a mechanism for managing disk partitions in a Linux environment, a logical layer that is built on top of hard disks and partitions and under a file system to improve the flexibility of disk partition management. RHEL5 the default installed partition format is the format of the LVM logical volume, it is important to note that the/boot partition cannot be created based on LVM and must be independent.

LVM contains: PV, VG, LV

Pv:physical Volume

This is the LVM lowest layer device, which is a multi-block physical disk.

Vg:volume Group

Using multiple physical disks to make up a volume group makes it easy for KVM to manage the volume, but it cannot be used directly, which is equivalent to extending the partition.

Lv:logical Volume

The LV is used to create the VG as a logical volume. Multiple logical volumes can be created in one VG.

Therefore, when the LV is not enough, that can be extended without exceeding the VG boundary, and the VG is not enough, then only need to add PV in the VG.

This article from "Liang Childe" blog, please be sure to keep this source http://iyull.blog.51cto.com/4664834/1886286

Linux Basic--LVM Management