linux cant mount /home

[aaaaaarko]

Last time i logged in from a user account named arka.bt when i tryed to log in next that user account was not there and in the /Home directory there was almost 40 gb free space.now it is showing 4.7 gb free space and the directory arka is not there.when i faced this problem before i reinstalled the linux.but now i have some important date on that home partition.

[root@localhost ~]# fdisk -l

Disk /dev/sda: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 * 1 13 104391 83 Linux
/dev/sda2 14 1288 10241437+ 83 Linux
/dev/sda3 1289 1419 1052257+ 82 Linux swap / Solaris
/dev/sda4 1420 9729 66750075 5 Extended
/dev/sda5 1420 9729 66750043+ 8e Linux LVM

[root@localhost ~]# df -H
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 11G 4.6G 5.1G 48% /
/dev/sda1 104M 15M 84M 16% /boot
tmpfs 260M 0 260M 0% /dev/shm

linux doesnt able to mount that volume. At the time of linux booting it shows mount local filesyatem fail

i used

mount /dev/sda4 /

and

mount/dev/mapper/homevg /home

nothing worked out.....plzzzz help...very urgent

[tpl]

well: one problem with

"mount /dev/sda4 /"

is that sda4 is the extended partition: you want sda5

[aaaaaarko]

[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 9.5G 4.3G 4.7G 48% /
/dev/sda1 99M 15M 80M 16% /boot
tmpfs 248M 0 248M 0% /dev/shm

look there is no filesystem named home...............but the result below shoud be the real result

[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 9.5G 4.3G 4.8G 48% /
/dev/sda1 99M 15M 80M 16% /boot
tmpfs 248M 0 248M 0% /dev/shm
/dev/mapper/homevg-home--snapshot
9.5G 151M 8.9G 2% /snapshot
/dev/mapper/home 54G 3.4G 47G 7% /home

i have this partition before