12.7. Disk Druid

Disk Druid is an interactive program for editing disk partitions. Users run it only within the Fedora installation system. Disk Druid enables you to configure Linux software RAID and LVM to provide more extensible and reliable data storage.

[Note] Modifying the Default LVM Layout

The default layout pools all of the available storage into a single LVM physical volume, with one LVM logical volume for the system. To make capacity available for additional partitions, Edit the logical volume with the mount point /, and reduce its size as necessary.

Disk Druid displays the following actions in the installation program:

New

Select this option to add a partition or LVM physical volume to the disk. In the Add partition dialog, choose a mount point and a partition type. If you have more than one disk on the system, choose which disks the partition may inhabit. Indicate a size in megabytes for the partition. If you wish to encrypt the partition, select that option.

[Important] Illegal Partitions

The /bin/, /dev/, /etc/, /lib/, /proc/, /root/, and /sbin/ directories may not be used for separate partitions in Disk Druid. These directories reside on the / (root) partition.

The /boot partition may not reside on an LVM volume group. Create the /boot partition before configuring any volume groups.

You may also choose from three options for sizing your partition:

Fixed size

Use a fixed size as close to your entry as possible.

Fill all space up to

Grow the partition to a maximum size of your choice.

Fill to maximum allowable size

Grow the partition until it fills the remainder of the selected disks.

[Note] Partition Sizes

The actual partition on the disk may be slightly smaller or larger than your choice. Disk geometry issues cause this effect, not an error or bug.

Select the Encrypt partition option to encrypt all information on the disk partition.

After you enter the details for your partition, select OK to continue. If you chose to encrypt the partition, the installer prompts you to assign a passphrase by typing it twice. For hints on using good passphrases, refer to Chapter 11, Set the Root Password.

Edit

Select this option to edit an existing partition, LVM volume group, or an LVM physical volume that is not yet part of a volume group. To change the size of a LVM physical volume partition, first remove it from any volume groups.

[Warning] Removing LVM Physical Volumes

If you remove an LVM physical volume from a volume group, you erase any logical volumes it contains.

Edit a partition to change its size, mount point, or file system type. Use this function to:

  • correct a mistake in setting up your partitions

  • migrate Linux partitions if you are upgrading or reinstalling Fedora

  • provide a mount point for non-Linux partitions such as those used on some Windows operating systems

  • resize an existing NTFS, ext2, or ext3 partition

[Note] Windows Partitions

You may not label Windows partitions that use the NTFS file system with a mount point in the Fedora installer. You may label vfat (FAT16 or FAT32) partitions with a mount point.

If you need to make drastic changes to your partition configuration, you may want to delete partitions and start again. If your disk contains data that you need to keep, back it up before you edit any partitions. If you edit the size of a partition, you may lose all data on it.

If your system contains many separate partitions for system and user data, it is easier to upgrade your system. The installation program allows you to erase or retain data on specific partitions. If your user data is on a separate /home partition, you can retain that data while erasing system partitions such as /boot.

To change the partition's mount point, enter the new mount point in the space provided. To resize the partition, select Resize and enter a new size, or click and hold the arrow controls to dial the size up or down as needed. To encrypt the partition, select Encrypt and provide a passphrase by typing it twice at the prompt. Refer to Chapter 11, Set the Root Password for information on using good passphrases.

Delete

Select this option to erase an existing partition or LVM physical volume. To delete an LVM physical volume, first delete any volume groups of which that physical volume is a member.

If you make a mistake, use the Reset option to abandon all the changes you have made.

Reset

Select this option to force Disk Druid to abandon all changes made to disk partitions.

RAID

Select this option to set up software RAID on your Fedora system.

Create a software RAID partition

Choose this option to add a partition for software RAID. This option is the only choice available if your disk contains no software RAID partitions.

Create a RAID device

Choose this option to construct a RAID device from two or more existing software RAID partitions. This option is available if two or more software RAID partitions have been configured.

Clone a drive to create a RAID device

Choose this option to set up a RAID mirror of an existing disk. This option is available if two or more disks are attached to the system.

LVM

Select this option to set up LVM on your Fedora system. First create at least one partition or software RAID device as an LVM physical volume, using the New dialog. For more information on LVM, refer to Section 12.3, “Understanding LVM”.

To assign one or more physical volumes to a volume group, first name the volume group. Then select the physical volumes to be used in the volume group. Finally, configure logical volumes on any volume groups using the Add, Edit and Delete options.

You may not remove a physical volume from a volume group if doing so would leave insufficient space for that group's logical volumes. Take for example a volume group made up of two 5 GB LVM physical volume partitions, which contains an 8 GB logical volume. The installer would not allow you to remove either of the component physical volumes, since that would leave only 5 GB in the group for an 8 GB logical volume. If you reduce the total size of any logical volumes appropriately, you may then remove a physical volume from the volume group. In the example, reducing the size of the logical volume to 4 GB would allow you to remove one of the 5 GB physical volumes.

[Important] LVM Unavailable in Text Installs

LVM initial set up is not available in a text-mode installation. The installer allows you to edit pre-configured LVM volumes. If you need to create an LVM configuration from scratch, hit Alt+F2 to use the terminal, and run the lvm command. To return to the text-mode installation, hit Alt+F1.

After you finish setting up and reviewing your partition configuration, select Next to continue the installation process.