Command

In &partman; commands are what jobs are made up of. These are very low level steps being taken, often executed by an external tool, and only visible in the detailed progress report.

The user normally does not have to bother with commands at all.

Cylinder

A unit used to divide up a device. Some operating systems and many disk tools require partitions to begin and end on a cylinder. &partman; therefore automatically snaps partitions to cylinder boundaries when changing their start or end.

Cylinder Size

The number of sectors per cylinder on a device. Calculated as the number of heads multiplied by the number of sectors per track.

Device

A physical disk device. Physical disk devices are divided into logical sections called partitions with the use of partition tables.

Disk Label

Another name for a partition table stemming from the SUN/BSD world.

They are easy to mix up, but a disk label has nothing to do with a file system label.

See this Wikipedia entry for details on the name.

Extended Partition

A partition that contains other partitions. Extended partitions can only be primary partitions themselves. Whether extended partitions are available or not depends on the partition table type used. MS-DOS partition tables allow one extended partition per device.

File System

A file system defines how the storage of data (files with their metadata, folders and their metadata, free space) is organized within a partition. There are various different types of file systems, some coming originally from the Unix/Linux world, some not. Examples for commonly used file systems on Unix/Linux are Btrfs, ext4 and XFS.

File System Label

A title of a file system. Some file systems (among them Btrfs, ext2/3/4, FAT16/32 and NTFS) support setting a label for the file system so it can be identified in tools like &partman; or other applications.

They are easy to mix up, but a file system label has nothing to do with a disk label.

Flag
GPT

A modern partition table format supported by most modern computers and operating systems. It supports more than 4 primary partitions unlike older MS-DOS partition table.

Head

A unit used to divide up a device.

Job

In &partman; a number of jobs is what operations are made up of. You normally do not have to bother with jobs at all; it only becomes apparent when applying the list of pending operations: &partman; will then show a progress dialog that is made up of all operations and their jobs and show which operation and which job is currently being executed.

Label

Either a disk label or a file system label.

Logical Partition

A partition inside an extended partition.

LUKS

Linux Unified Key Setup is the standard encryption format for Linux.

LVM

LVM is a system for managing logical partitions that is more flexible than normal partitions. It consists of three main components:

- LVM physical volumes are partitions on the disk whose space is managed by LVM.
- LVM volume group is a collection of LVM physical volumes that can be partitioned into logical partitions. It might be used to create file systems spanning over multiple devices or to split encrypted LUKS volume into smaller partitions.
- LVM logical volumes are similar to normal partitions except that they reside on LVM volume group. Also, the location of LVM logical partitions does not matter and they do not have to be physically contiguous. Therefore, &partman; does not allow to move LVM logical volumes and displays the remaining free space at the end of the device.

Operation

&partman; divides the work it does into operations, jobs and commands.

Operations are the most visible of the three. If you pick an action in the graphical user interface, this will likely result in a new operation being added to the list of pending operations. The idea behind that is: You will most probably want to set up quite a number of steps to transform the current state of your disk devices to the state you have in mind. Some of these steps may take quite a long time to execute (like copying a large file system or resizing a file system that is nearly full). To save you from having to sit in front of your computer for a long time waiting for one step to finish and then starting the next one, operations allow you to exactly specify how the computer's devices should look like once everything is finished, then let &partman; apply the operations and come back when it has executed all of them.

Operations are kept in a list of pending operations. As long as an operation has not been applied it can still be taken back easily and nothing will have been modified.

Partition

A section of a hard disk device that can hold a file system or other partitions. Without at least one valid partition, a disk can not be used.

Partition Flag

A marker for a partition. The availability of these flags depends on the type of partition table used.

Partition Table

A small section at the beginning of a device used to store information about the layout of the device's partitions. There are different types of partition tables, each with their own limitations.

Sometimes also referred to as disk label.

Primary Partition

A partition directly inside a partition table, as opposed to logical partitions, which are in extended partitions.

Partition tables usually impose restrictions on the maximum number of primary partitions that can be created on a device. For MS-DOS type partition tables, for example, this maximum number is four.

Sector

A unit used to divide up a device. Partitions must always begin and end on a sector.

Sector Size

The number of bytes per sector on a device. The sector size of most devices in use today is 512 bytes.