I have upgraded my VMWare VPS and I still have only 10 Gb disk space. After checking fdisk I saw there is 20GB more but it's not mounted yet.

# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
8.6G 7.9G 334M 97% /
/dev/sda1 99M 12M 82M 13% /boot
tmpfs 1.5G 0 1.5G 0% /dev/shm

# fdisk -l
Disk /dev/sda: 10.7 GB, 10737418240 bytes
255 heads, 63 sectors/track, 1305 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 1305 10377990 8e Linux LVM

Disk /dev/sdb: 23.6 GB, 23622320128 bytes
255 heads, 63 sectors/track, 2871 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/sdb doesn't contain a valid partition table

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Now how could I mount these 20 GB to my Linux partition - /dev/sda

Thanks

pvcreate + vgextend + lvextend + resize2fs (or ext2online depending on distro & version, which you failed to mention).

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