Trying to mount a partition with LVM2 volume might result in the following error:
mount unknown filesystem type 'lvm2_member'
If so, use this workaround:
apt-get install lvm2
vgscan # find volume group
vgdisplay # show information about volume group
vgchange -ay ubuntu-vg # make partitions in volume group "ubuntu-vg" active
lvs # shows volumes in volume group
mount /dev/ubuntu-vg/ubuntu-lv /media/
mount syntax after activating volume:
mount /dev/volume-group-name/volume-name /destination