The LVM Thread

[The Doctor]

Resize Linux storage with LVM

You need more space on your server/desktop/etc..  This guide will help you add it to the volume you’re currently using on your system. For the sake of making this an easy-to-follow guide, we’ll assume that  you already have the new drive showing in your Linux installation from fdisk, but it’s not yet usable (ie: you made it available from shared storage, you installed a new harddrive, etc..).

[The Doctor]

As mentioned above, Fdisk is a great Linux partitioning tool.  This article details those commands:

How to Use Fdisk to Manage Partitions on Linux

GParted, available within most Linux distros and Parted Magic, is another great GUI tool for Linux and Windows.

See:
GParted partitioning software - Full tutorial

[The Doctor]

Why you should check out LVM

LVM (currently released as LVM2), the "logical volume manager", is a flexible storage manager for the Linux kernel. It allows you to add, remove and resize partitions to suit your needs. Instead of having to predict how your disk space is going to be use when your install a new server, you dedicate a good amount of disk space to LVM and then can make changes to how that storage is allocated when you need.