Introduction

LVM, or Logical Volume Management, is a storage device management technology that gives users the power to pool and abstract the physical layout of component storage devices for flexible administration. Utilizing the device mapper Linux kernel framework, the current iteration, LVM2, can be used to gather existing storage devices into groups and allocate logical units from the combined space as needed.

The main advantages of LVM are increased abstraction, flexibility, and control. Logical volumes can have meaningful names like “databases” or “root-backup”. Volumes can also be resized dynamically as space requirements change, and migrated between physical devices within the pool on a running system or exported. LVM also offers advanced features like snapshotting, striping, and mirroring.

In this guide, you’ll learn how LVM works and practice basic commands to get up and running quickly on a bare metal machine.

Before diving into LVM administrative commands, it is important to have a basic understanding of how LVM organizes storage devices and some of the terminology it employs.

LVM Storage Management Structures

LVM functions by layering abstractions on top of physical storage devices. The basic layers that LVM uses, starting with the most primitive, are:

• Physical Volumes: The LVM utility prefix for physical volumes is PV.. This physicallyl blocks devices or other disk-like devices (for example, other devices created by device mapper, like RAID arrays) and are used by LVM as the raw building material for higher levels of abstraction. Physical volumes are regular storage devices. LVM writes a header to the device to allocate it for management.

• Volume Groups: The LVM utility prefix for volume groups is VG.. LVM combines physical volumes into storage pools known as volume groups. Volume groups abstract the characteristics of the underlying devices and function as a unified logical device with combined storage capacity of the component physical volumes.

• Logical Volumes: The LVM utility prefix for logical volumes is LV generic LVM utilities might begin with LVM. A volume group can be sliced up into any number of logical volumes. Logical volumes are functionally equivalent to partitions on a physical disk, but with much more flexibility. Logical volumes are the primary component that users and applications will interact with.

LVM can be used to combine physical volumes into volume groups to unify the storage space available on a system. Afterwards, administrators can segment the volume group into arbitrary logical volumes, which act as flexible partitions.

What is LVM Simple Way ?

LVM (Logical Volume Manager) allows you to manage disk space flexibly by abstracting physical storage into logical volumes. You can resize, combine, and manage volumes more easily than with traditional partitions.