Introduction to Linux LVM and How to Extend LVM with the PE Concept（linuxlvmpe）

Introduction to Linux LVM and How to Extend LVM with the PE Concept

Logical Volume Manager (LVM) is a disk partitioning feature of the Linux operating system that allows users to easily resize and merge existing partitions. It allows users to create, delete, and resize partitions on the fly and helps to isolate logical groups of data that can be stored much more efficiently than traditional partitioning schemes. LVM is a powerful data management tool, and it is the foundation on which the Linux Virtual Server (LVS) platform is built.

In this article, we will provide an introduction to the concepts of the Linux LVM and the Physical Extent (PE) unit, which allows for greater flexibility in extending and scaling partitions. We will also provide a small example of how to extend an LVM partition with the use of a PE.

The Linux LVM system is based on the concept of Physical and Logical volumes. Physical volumes are essentially physical storage libers that are provided by the system and can contain multiple Logical Volumes. Logical Volumes can be seen as individual partitions that can easily be resized, moved, and merged with other partitions. The basic physical unit of a Physical Volume is the Physical Extent (PE). PEs are essentially portions of the physical volume, and each PE can be precisely resized and managed independently.

Using the PE concept, LVM allows users to easily extend an existing partition into an additional physical volume. This is useful for situations where additional storage space is needed to add more data or to scale an existing partition. For example, let us assume that we have an existing Logical Volume of 6000 PEs, and we want to add 2000 PEs from a new Physical Volume. In this scenario, we would first need to create the new Physical Volume, and then we can use the “lvconvert” command to start the process of merging the new PEs.

Once the new Physical Volume is created and attached, the lvconvert command can be used to extend the existing Logical Volume by 2000 PEs. This is done by running the command “lvconvert –merge vgname/lvname –extents 2000”. This command will extend the existing Logical Volume to include 2000 extra PEs from the new Physical Volume.

In conclusion, the Linux LVM system is a powerful data management tool that allows users to easily resize and extend existing partitions. The Physical Extent concept allows users to efficiently and precisely manage individual partitions, creating much greater flexibility and scalability in the system. This article provided an introduction to the concept of LVM and the PE unit, as well as a small example of how to extend an existing partition with the use of PE.