The lvreduce command changes either the number of logical extents allocated to a logical volume specified with the LogicalVolumePath parameter or the number of physical extents allocated to each logical extent in the logical volume. The change is determined according to which command flags you use.
MirrorCopies (that is, mirrors) can be either 0 or 1. This means that beyond the original copy, no other (0) or one (1) mirror copy will contain the same data as the original copy.
MirrorCopies must be less than the current number of mirrors for the logical volume. Either this option or the -l option must be supplied. Decreases the number of logical extents allocated to the LogicalVolumePath. LogicalExtentsNumber must be less than the number of logical extents previously allocated to LogicalVolumePath.
LogicalExtentsNumber represents the new total number of logical extents within LogicalVolumePath. The change is accomplished by deallocating the number of logical extents represented by the difference between the previous number of extents and LogicalExtentsNumber.
The lvreduce command asks for confirmation if you do not use the -f flag.
You must use either this option (-l) or the -m option.
The Logical Volume Manager does not store any information about which physical extents contain useful data; therefore, using the -l option might lead to the loss of useful data.
Commands: lvcreate(8), lvdisplay(8), lvextend(8), pvchange(8), pvdisplay(8) delim off