Logical Volume Manager (Linux)

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"Logical Volume Manager" redirects here. It is not to be confused with logical volume manager.
Linux Logical Volume Manager
Original author(s) Heinz Mauelshagen[1]
Stable release 2.02.107[2] / 25 June 2014; 14 days ago (2014-06-25)
Written in C
Operating system Linux
License GNU GPL
Website sources.redhat.com/lvm2/

LVM is a logical volume manager for the Linux kernel that manages disk drives and similar mass-storage devices. Heinz Mauelshagen wrote the original code back in 1998, taking its primary design guidelines from the HP-UX's volume manager.[citation needed]

The installers for the Arch Linux, CrunchBang, CentOS, Debian, Fedora, Gentoo, Mandriva, MontaVista Linux, openSUSE, Pardus, Red Hat Enterprise Linux, Slackware, SLED, SLES, Linux Mint, Kali Linux, and Ubuntu distributions are LVM-aware and can install a bootable system with a root filesystem on a logical volume.

Common uses[edit]

LVM is commonly used for the following purposes:

  • On small systems (like a desktop at home), instead of having to estimate at installation time how big a partition might need to be in the future, LVM allows file systems to be easily resized later as needed.
  • Performing consistent backups by taking snapshots of the logical volumes.
  • the Ganeti solution stack relies on the Linux Logical Volume Manager

LVM can be considered as a thin software layer on top of the hard disks and partitions, which creates an abstraction of continuity and ease-of-use for managing hard drive replacement, re-partitioning, and backup.


The LVM can:

  • Create RAID logical volumes (available in newer LVM implementations): RAID 1, RAID 5, RAID 6, etc.[3]
  • Configure a RAID 1 backend device (a PV) as write-mostly, resulting in reads being avoided to such devices unless necessary.[4]
  • Allocate thin-provisioned logical volumes from a pool.[5]
  • Move online logical volumes between PVs.
  • SSD caching support, based on top of dm-cache. For example, having both, slow hard disks and fast SSDs, and you want to use the SSDs to act as fast persistent caches to speed up access to slow hard disk[6]

The LVM will also work in a shared-storage cluster (where disks holding the PVs are shared between multiple host computers), but requires an additional daemon to propagate state changes between cluster nodes.


Relationship between various elements of the LVM.

LVM keeps a metadata header at the start of every physical volume, each of which is uniquely identified by a UUID. Each PV's header is a complete copy of the entire volume group's layout, including the UUIDs of all other PVs, the UUIDs of all logical volumes and an allocation map of PEs to LEs. This simplifies data recovery in the event of PV loss.



  1. Searches for PVs in all available block devices.
  2. Parses the metadata header in each PV found.
  3. Computes the layouts of all visible volume groups.
    2. Creates a new, empty device mapping.





Until Linux kernel 2.6.31,[7] write barriers were not supported (fully supported in 2.6.33). This means that the guarantee against filesystem corruption offered by journaled file systems like ext3 and XFS was negated under some circumstances.[8]

See also[edit]


  1. ^ "LVM README". 2003-11-17. Retrieved 2014-06-25. 
  2. ^ "[lvm-devel] LVM2 release 2.02.107: New argument --select". redhat.com. 2014-06-25. Retrieved 2014-06-25. 
  3. ^ "4.4.15. RAID Logical Volumes". Access.redhat.com. Retrieved 2014-06-20. 
  6. ^ "Using LVM’s new cache feature". Retrieved 07.07.2014. 
  7. ^ "Bug 9554 - write barriers over device mapper are not supported". 2009-07-01. Retrieved 2010-01-24. 

Further reading[edit]

  1. Lewis, AJ (2006-11-27). "LVM HOWTO". Linux Documentation Project. Retrieved 2008-03-04. .
  2. US patent 5129088, Auslander, et al., "Data Processing Method to Create Virtual Disks from Non-Contiguous Groups of Logically Contiguous Addressable Blocks of Direct Access Storage Device", issued 1992-7-7  (fundamental patent).
  3. "RedHat Linux: What is Logical Volume Manager or LVM?". techmagazinez.com. 6 August 2013. Retrieved 4 September 2013. 
  4. "LVM2 Resource Page". sourceware.org. 8 June 2012. Retrieved 4 September 2013. 
  5. "How-To: Install Ubuntu on LVM partitions". Debuntu.org. 28 July 2007. Retrieved 4 September 2013. 
  6. "Logical Volume Manager". markus-gattol.name. 13 July 2013.