Logical Volume Management (LVM) is a method of allocating space on mass-storage devices that is more flexible than conventional partitioning schemes to store volumes. LVM is a tool for logical volume management which includes allocating disks, striping, mirroring, and resizing logical volumes. LVM is a device mapper framework that provides logical volume management for the Linux kernel).
Here are some key features of LVM:
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Physical Volumes (PV): Storage disks are designated as Physical Volumes, or storage capacity usable by LVM.
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Volume Groups (VG): A hard drive or set of hard drives is allocated to one or more Volume Groups. LVM physical volumes can be placed on other block devices which might span two or more disks. The physical volumes are combined into logical volumes, with the exception of the /boot partition.
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Logical Volumes (LV): The pooled Logical Extents (LEs) can then be concatenated together into virtual disk partitions called Logical Volumes or LVs. Systems can use LVs as raw block devices just like disk partitions: creating mountable file systems on them, or using them as swap storage.
LVM is used for the following purposes):
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On small systems (like a desktop), instead of having to estimate at installation time how big a partition might need to be, LVM allows filesystems to be easily resized as needed.
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Performing consistent backups by taking snapshots of the logical volumes.
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Encrypting multiple physical partitions with one password.
One of the benefits of LVM configurations is the ability to scale storage capacity easily and quickly. Its worthwhile to note that you can also scale storage capacity down with LVM. That means that if storage capacity is over-allocated, you can shrink it.
LVM is a powerful tool that can be used to manage storage in Linux systems. It provides a flexible and scalable way to allocate and manage storage space on mass-storage devices.
