Fedora Linux

Using Logical Volume Management

Fedora uses the Linux Logical Volume Management (LVM) system by default for disk storage. LVM combines one or more disk partitions, called Physical Volumes (PVs), into a pool of storage called a Volume Group (VG). From this volume group, one or more Logical Volumes (LVs) are allocated. Each LV is used as a block storage device to contain a filesystem or a swapspace.

Here’s where the fun begins: LVs can be resized, created, or deleted on the fly, and disks can be added and deleted—while the system is in use!

Warning

When changing a storage configuration, it is possible to make a mistake and lose data. Take your time, ensure that you are confident of what each step will do before performing it, and make sure you back up your data before performing any LVM operations.

How Do I Do That?

Fedora Core permits you to manage logical volumes graphically or from the command line.

Tip

In the examples given here, the volume-group and logical-volume names recommended in Chapter 1 have been used: the volume group is main, and the logical volumes are named root, home, and swap.

If you used the Fedora default names, the main volume group will be named VolGroup00, and the logical volumes will be named LogVol00, LogVol01, and so forth.

Although you can increase or decrease the size of any logical volume at any time, an ext3 filesystem within a logical volume can be reduced in size only when it is not in use (unmounted). If the filesystem is the root filesystem, it is in use ...