To mount an LVM volume on Linux, first set the volume to the “active” state:
vgchange -ay
Mount the drive as usual. When finished, the drive must be unmounted and the command
vgchange -an
must be executed. Note that this could turn off all of your volume groups, so you should be careful and use a different command if you have more than one volume group.
Alternatively you can activate a specific volume group with the command
vgchange -a y <VolGroupName>