# fdisk
# partprobe
# pvcreate /dev/vda6
# vgcreate -s 8M vg1 /dev/vda6 -s
# lvcreate -n lvshare -l 50 vg1 -l
# mkfs.ext4 /dev/vg1/lvshare
# mkdir -p /mnt/data
# vim /etc/fstab
/dev/vg1/lvshare /mnt/data ext4 defaults 0 0
# mount -a
# df -h

see explanation below.
Explanation
The LVM system organizes hard disks into Logical Volume (LV) groups. Essentially, physical hard disk partitions (or possibly RAID arrays) are set up in a bunch of equal sized chunks known as Physical Extents (PE). As there are several other concepts associated with the LVM system, let's start with some basic definitions:
Physical Volume (PV) is the standard partition that you add to the LVM mix. Normally, a physical volume is a standard primary or logical partition. It can also be a RAID array.
Physical Extent (PE) is a chunk of disk space. Every PV is divided into a number of equal sized PEs. Every PE in a LV group is the same size. Different LV groups can have different sized PEs.
Logical Extent (LE) is also a chunk of disk space. Every LE is mapped to a specific PE.
Logical Volume (LV) is composed of a group of LEs. You can mount a file system such as /home and /var on an LV.
Volume Group (VG) is composed of a group of LVs. It is the organizational group for LVM. Most of the commands that you'll use apply to a specific VG.
* Verify the size of Logical Volume: lvdisplay /dev/vg0/lv1
* Verify the Size on mounted directory: df -h or df -h mounted directory name
* Use: lvextend -L+400M /dev/vg0/lv1
* ext2online -d /dev/vg0/lv1 to bring extended size online.
* Again Verify using lvdisplay and df -h command.

# which echo
# crontab -e
23 14 * * * /bin/echo hello
# crontab -l (Verify)

See explanation below.
Explanation/Reference:
Explanation: /etc/init.d/rpcbind start
/etc/init.d/nfslock start
/etc/init.d/nfs start
chkconfig rpcbind on
chkconfig nfslock on
chkconfig nfs on
showmount -e localhost

# vgdisplay
(Check the capacity of vg, if the capacity is not enough, need to create pv , vgextend , lvextend)
# lvdisplay (Check lv)
# lvextend -L +110M /dev/vg2/lv2
# resize2fs /dev/vg2/lv2
mount -a
(Verify)
------------------------------------------------------------------------------- (Decrease lvm)
# umount /media
# fsck -f /dev/vg2/lv2
# resize2fs -f /dev/vg2/lv2 100M
# lvreduce -L 100M /dev/vg2/lv2
# mount -a
# lvdisplay (Verify)
OR
# e2fsck -f /dev/vg1/lvm02
# resize2fs -f /dev/vg1/lvm02
# mount /dev/vg1/lvm01 /mnt
# lvreduce -L 1G -n /dev/vg1/lvm02
# lvdisplay (Verify)