$ Linux Command

System

vgscan

Scan all disks for LVM volume groups.

lvmvolume groupscandiscoverdetect

Additional Notes

vgscan scans the system for LVM volume groups by checking all available block devices for LVM metadata. It reads the LVM labels and metadata areas and registers any discovered volume groups with the LVM subsystem. It also creates or updates the LVM cache file (/etc/lvm/cache/.cache) that other LVM commands use.

vgscan is commonly run after adding new disks, recovering from a missing device, or when LVM commands are not seeing all expected volume groups. It is automatically run at boot by LVM init scripts or systemd services.

Syntax

vgscan [options]

Parameters

  • options: Flags that change how vgscan behaves.
  • target: Optional file, device, interface, user, service, or command target when the command supports one.

Common Options

  • -v, --verbose: Show detailed information about each VG found.
  • --cache: Update the LVM cache file (the default behavior).
  • --mknodes: Create the /dev/VG_NAME/ device nodes for all LVs.
  • --ignorelockingfailure: Ignore lock failures (useful in recovery scenarios).
  • -P, --partial: Allow activation of VGs with missing PVs.
  • --uvuuid: Scan in UUID-based mode.

Examples

vgscan

Scan all disks for volume groups.

vgscan -v

Scan with verbose output showing device paths and VG details.

vgscan --mknodes

Scan and ensure all LV device nodes exist.

vgscan --cache

Force update of the LVM cache file.

Practical Notes

  • vgscan itself does not activate volume groups. Run vgchange -ay after scanning to activate them.
  • After adding a new disk that belongs to an existing VG, vgscan discovers the VG via the new PV.
  • In recovery scenarios, --ignorelockingfailure and -P can help when a PV is missing but the VG should still be visible.
  • The cache file lists all PVs and VGs; if it becomes stale, vgscan --cache refreshes it.
  • For more detailed information on a specific VG, use vgdisplay.