To add extra partition and increase the lvm volume do following:

1. Format the new harddrive:

~#:fdisk /dev/sdb(1) n(2) p ->1-4(3) w

2. To see all LVM Partition:

~#:lvscan

3. To see all physical volume and their status, whether it is devoted to a groub or not:

~#:lvmdiskscan

4. To change a partition state to a LVM Physical Volume:

~#:pvcreate /dev/sdb1

5. To see all LVM groups:

~#:vgdiplay

6. To add the new LVM physical volume to the group listed above:

~#:vgextend [Group Name] /dev/sdb1

7. To see all physical volume dedicated to a group:

~#:vgdisplay [Group Name]

8. To create a new LVM logical volume in a group:

~#:lvcreate -l 100%FREE -n [ a name you want ] [ LVM Group ]

* this command will devote all free space in a group to the new one called [a name you want]

9. To extend current LVM logical partition and increase the system space:

~#:lvextend -l +100%FREE /dev/[LVM Group]/[name of current logical volume] #/dev/LVMgr/LogVol01

10. To remove a logical volume:

~#:lvremove /dev/[LVM Group]/[name of poor logical volume]

* If you increase the logical volume of a system, it should be informed by following command:

~#:resize2fs /dev/[LVM Group]/[name of lvm logical volume]