Create a snapshot logical volume (or snapshot) for an existing, so
called original logical volume (or origin). Snapshots provide a
‘frozen image’ of the contents of the origin while the origin can
still be updated. They enable consistent backups and online recovery of
removed/overwritten data/files. The snapshot does not need the same
amount of storage the origin has. In a typical scenario, 15-20% might be
enough. In case the snapshot runs out of storage, use lvextend(8)
to grow it. Shrinking a snapshot is supported by lvreduce(8) as well.
Run lvdisplay(8) on the snapshot in order to check how much data is
allocated to it。
