= UUID Reference
:page-parent: Development
:page-nav_order: 6

// SPDX-FileCopyrightText: 2022 Alyssa Ross <hi@alyssa.is>
// SPDX-License-Identifier: GFDL-1.3-no-invariants-or-later OR CC-BY-SA-4.0

https://en.wikipedia.org/wiki/Universally_unique_identifier[UUIDs] are
used extensively throughout Spectrum.  When encountering a UUID in the
codebase, it can be difficult to understand what exactly the UUID
means, and where it originates from -- is it from some standard, or
Spectrum-specific?

To solve this problem, this reference documents all of the UUIDs used
in Spectrum.

== https://en.wikipedia.org/wiki/GUID_Partition_Table[GPT] Partition Types

=== `c12a7328-f81f-11d2-ba4b-00a0c93ec93b`

"EFI System Partition", from the https://uefi.org/specifications[UEFI
Specification].

=== `b921b045-1df0-41c3-af44-4c6f280d3fae`

"Root Partition (64-bit ARM/AArch64)" from the
https://uapi-group.org/specifications/specs/discoverable_partitions_specification/[Discoverable Partitions
Specification].

=== `4f68bce3-e8cd-4db1-96e7-fbcaf984b709`

"Root Partition (amd64/x86_64)" from the
https://uapi-group.org/specifications/specs/discoverable_partitions_specification/[Discoverable Partitions
Specification].

=== `df3300ce-d69f-4c92-978c-9bfb0f38d820`

"Root Verity Partition (64-bit ARM/AArch64)" from the
https://uapi-group.org/specifications/specs/discoverable_partitions_specification/[Discoverable Partitions
Specification].

=== `2c7357ed-ebd2-46d9-aec1-23d437ec2bf5`

"Root Verity Partition (amd64/x86_64)" from the
https://uapi-group.org/specifications/specs/discoverable_partitions_specification/[Discoverable Partitions
Specification].

=== `56a3bbc3-aefa-43d9-a64d-7b3fd59bbc4e`

https://github.com/endlessm/eos-installer["eosimages"] partition on the
Spectrum combined live system / installer image.

== Combined Image Partition IDs

These UUIDs are used as the unique partition identifiers for the
Spectrum combined live system / installer image.

=== `6e23b026-9f1e-479d-8a58-a0cda382e1ce`

The Spectrum installer system.

=== `18f2ccff-92f1-4bb1-a80e-24f76ecda90c`

The not-yet-used B verity partition.

=== `ec0c5ff3-f6b1-4adf-82b4-61336c4d135f`

The not-yet-used B root filesystem partition.

'''

== Finding Undocumented UUIDs

Running the `Documentation/scripts/undocumented-uuids.sh` script from
the root of the Spectrum repository will scan the entire tree for
UUIDs not mentioned in this document.