<?xml version="1.0"?> <!--*-nxml-*--> <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> <!-- This file is part of systemd. Copyright 2013 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. --> <refentry id="systemd-gpt-auto-generator"> <refentryinfo> <title>systemd-gpt-auto-generator</title> <productname>systemd</productname> <authorgroup> <author> <contrib>Developer</contrib> <firstname>Lennart</firstname> <surname>Poettering</surname> <email>lennart@poettering.net</email> </author> </authorgroup> </refentryinfo> <refmeta> <refentrytitle>systemd-gpt-auto-generator</refentrytitle> <manvolnum>8</manvolnum> </refmeta> <refnamediv> <refname>systemd-gpt-auto-generator</refname> <refpurpose>Generator for automatically discovering and mounting root, <filename>/home</filename> and <filename>/srv</filename> partitions, as well as discovering and enabling swap partitions, based on GPT partition type GUIDs.</refpurpose> </refnamediv> <refsynopsisdiv> <para><filename>/usr/lib/systemd/system-generators/systemd-gpt-auto-generator</filename></para> </refsynopsisdiv> <refsect1> <title>Description</title> <para><filename>systemd-gpt-auto-generator</filename> is a unit generator that automatically discovers root, <filename>/home</filename>, <filename>/srv</filename> and swap partitions and creates mount and swap units for them, based on the partition type GUIDs of GUID partition tables (GPT). It implements the <ulink url="http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/">Discoverable Partitions Specification</ulink>. Note that this generator has no effect on non-GPT systems, or where the directories under the mount points are already non-empty. Also, on systems where the units are explicitly configured (for example, listed in <citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>), the units this generator creates are overriden, but additional automatic dependencies might be created.</para> <para>This generator will only look for root partitions on the same physical disk the EFI System Partition (ESP) is located on. It will only look for the other partitions on the same physical disk the root file system is located on. These partitions will not be searched on systems where the root file system is distributed on multiple disks, for example via btrfs RAID.</para> <para><filename>systemd-gpt-auto-generator</filename> is useful for centralizing file system configuration in the partition table and making manual configuration in <filename>/etc/fstab</filename> or suchlike unnecessary.</para> <para>This generator looks for the partitions based on their partition type GUID. The following partition type GUIDs are identified:</para> <table> <title>Partition Type GUIDs</title> <tgroup cols='3' align='left' colsep='1' rowsep='1'> <colspec colname="guid" /> <colspec colname="name" /> <colspec colname="explanation" /> <thead> <row> <entry>Partition Type GUID</entry> <entry>Name</entry> <entry>Explanation</entry> </row> </thead> <tbody> <row> <entry>44479540-f297-41b2-9af7-d131d5f0458a</entry> <entry><filename>Root Partition (x86)</filename></entry> <entry>On 32-bit x86 systems, the first x86 root partition on the disk the EFI ESP is located on is mounted to the root directory <filename>/</filename>.</entry> </row> <row> <entry>4f68bce3-e8cd-4db1-96e7-fbcaf984b709</entry> <entry><filename>Root Partition (x86-64)</filename></entry> <entry>On 64-bit x86 systems, the first x86-64 root partition on the disk the EFI ESP is located on is mounted to the root directory <filename>/</filename>.</entry> </row> <row> <entry>69dad710-2ce4-4e3c-b16c-21a1d49abed3</entry> <entry><filename>Root Partition (32-bit ARM)</filename></entry> <entry>On 32-bit ARM systems, the first ARM root partition on the disk the EFI ESP is located on is mounted to the root directory <filename>/</filename>.</entry> </row> <row> <entry>b921b045-1df0-41c3-af44-4c6f280d3fae</entry> <entry><filename>Root Partition (64-bit ARM)</filename></entry> <entry>On 64-bit ARM systems, the first ARM root partition on the disk the EFI ESP is located on is mounted to the root directory <filename>/</filename>.</entry> </row> <row> <entry>933ac7e1-2eb4-4f13-b844-0e14e2aef915</entry> <entry>Home Partition</entry> <entry>The first home partition on the disk the root partition is located on is mounted to <filename>/home</filename>.</entry> </row> <row> <entry>3b8f8425-20e0-4f3b-907f-1a25a76f98e8</entry> <entry>Server Data Partition</entry> <entry>The first server data partition on the disk the root partition is located on is mounted to <filename>/srv</filename>.</entry> </row> <row> <entry>0657fd6d-a4ab-43c4-84e5-0933c84b4f4f</entry> <entry>Swap</entry> <entry>All swap partitions located on the disk the root partition is located on are enabled.</entry> </row> </tbody> </tgroup> </table> <para>The <filename>/home</filename> and <filename>/srv</filename> partitions may be encrypted in LUKS format. In this case a device mapper device is set up under the names <filename>/dev/mapper/home</filename> and <filename>/dev/mapper/srv</filename>. Note that this might create conflicts if the same partition is listed in <filename>/etc/crypttab</filename> with a different device mapper device name.</para> <para>Mount and automount units for the EFI System Partition (ESP), mounting it to <filename>/boot</filename> are generated on EFI systems, where the boot loader communicates the used ESP to the operating system. Since this generator creates an automount unit, the mount will only be activated on-demand, when accessed. On systems where <filename>/boot</filename> is an explicitly configured mount (for example, listed in <citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>) or where the <filename>/boot</filename> mount point is non-empty, no mount units are generated.</para> <para>When using this generator in conjunction with btrfs file systems, make sure to set the correct default subvolumes on them, using <command>btrfs subvolume set-default</command>.</para> <para><filename>systemd-gpt-auto-generator</filename> implements <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> </refsect1> <refsect1> <title>See Also</title> <para> <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry><refentrytitle>systemd-cryptsetup@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>, <citerefentry project='man-pages'><refentrytitle>btrfs</refentrytitle><manvolnum>8</manvolnum></citerefentry> </para> </refsect1> </refentry>