man/systemd-gpt-auto-generator.xml

   1 <?xml version="1.0"?>
   2 <!--*-nxml-*-->
   3 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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   7   Copyright 2013 Lennart Poettering
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  22 <refentry id="systemd-gpt-auto-generator">
  23
  24         <refentryinfo>
  25                 <title>systemd-gpt-auto-generator</title>
  26                 <productname>systemd</productname>
  27
  28                 <authorgroup>
  29                         <author>
  30                                 <contrib>Developer</contrib>
  31                                 <firstname>Lennart</firstname>
  32                                 <surname>Poettering</surname>
  33                                 <email>lennart@poettering.net</email>
  34                         </author>
  35                 </authorgroup>
  36         </refentryinfo>
  37
  38         <refmeta>
  39                 <refentrytitle>systemd-gpt-auto-generator</refentrytitle>
  40                 <manvolnum>8</manvolnum>
  41         </refmeta>
  42
  43         <refnamediv>
  44                 <refname>systemd-gpt-auto-generator</refname>
  45                 <refpurpose>Generator for automatically discovering
  46                 and mounting root, <filename>/home</filename> and
  47                 <filename>/srv</filename> partitions, as well as
  48                 discovering and enabling swap partitions, based on GPT
  49                 partition type GUIDs.</refpurpose>
  50         </refnamediv>
  51
  52         <refsynopsisdiv>
  53                 <para><filename>/usr/lib/systemd/system-generators/systemd-gpt-auto-generator</filename></para>
  54         </refsynopsisdiv>
  55
  56         <refsect1>
  57                 <title>Description</title>
  58
  59                 <para><filename>systemd-gpt-auto-generator</filename>
  60                 is a unit generator that automatically discovers root,
  61                 <filename>/home</filename>, <filename>/srv</filename>
  62                 and swap partitions and creates mount and swap units
  63                 for them, based on the partition type GUIDs of
  64                 GUID partition tables (GPT). It implements the <ulink
  65                 url="http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/">Discoverable
  66                 Partitions Specification</ulink>. Note that this
  67                 generator has no effect on non-GPT systems, on systems
  68                 where the units are explicitly configured (for
  69                 example, listed in
  70                 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>),
  71                 or where the mount points are non-empty.</para>
  72
  73                 <para>This generator will only look for root
  74                 partitions on the same physical disk the EFI System
  75                 Partition (ESP) is located on. It will only look for
  76                 the other partitions on the same physical disk the
  77                 root file system is located on. These partitions will
  78                 not be searched on systems where the root file system is
  79                 distributed on multiple disks, for example via btrfs
  80                 RAID.</para>
  81
  82                 <para><filename>systemd-gpt-auto-generator</filename>
  83                 is useful for centralizing file system configuration
  84                 in the partition table and making manual configuration
  85                 in <filename>/etc/fstab</filename> or suchlike
  86                 unnecessary.</para>
  87
  88                 <para>This generator looks for the partitions based on
  89                 their partition type GUID. The following partition
  90                 type GUIDs are identified:</para>
  91
  92                 <table>
  93                         <title>Partition Type GUIDs</title>
  94                         <tgroup cols='3' align='left' colsep='1' rowsep='1'>
  95                                 <colspec colname="guid" />
  96                                 <colspec colname="name" />
  97                                 <colspec colname="explanation" />
  98                                 <thead>
  99                                         <row>
 100                                                 <entry>Partition Type GUID</entry>
 101                                                 <entry>Name</entry>
 102                                                 <entry>Explanation</entry>
 103                                         </row>
 104                                 </thead>
 105                                 <tbody>
 106                                         <row>
 107                                                 <entry>44479540-f297-41b2-9af7-d131d5f0458a</entry>
 108                                                 <entry><filename>Root Partition (x86)</filename></entry>
 109                                                 <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>
 110                                         </row>
 111                                         <row>
 112                                                 <entry>4f68bce3-e8cd-4db1-96e7-fbcaf984b709</entry>
 113                                                 <entry><filename>Root Partition (x86-64)</filename></entry>
 114                                                 <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>
 115                                         </row>
 116                                         <row>
 117                                                 <entry>69dad710-2ce4-4e3c-b16c-21a1d49abed3</entry>
 118                                                 <entry><filename>Root Partition (32-bit ARM)</filename></entry>
 119                                                 <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>
 120                                         </row>
 121                                         <row>
 122                                                 <entry>b921b045-1df0-41c3-af44-4c6f280d3fae</entry>
 123                                                 <entry><filename>Root Partition (64-bit ARM)</filename></entry>
 124                                                 <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>
 125                                         </row>
 126                                         <row>
 127                                                 <entry>933ac7e1-2eb4-4f13-b844-0e14e2aef915</entry>
 128                                                 <entry>Home Partition</entry>
 129                                                 <entry>The first home partition on the disk the root partition is located on is mounted to <filename>/home</filename>.</entry>
 130                                         </row>
 131                                         <row>
 132                                                 <entry>3b8f8425-20e0-4f3b-907f-1a25a76f98e8</entry>
 133                                                 <entry>Server Data Partition</entry>
 134                                                 <entry>The first server data partition on the disk the root partition is located on is mounted to <filename>/srv</filename>.</entry>
 135                                         </row>
 136                                         <row>
 137                                                 <entry>0657fd6d-a4ab-43c4-84e5-0933c84b4f4f</entry>
 138                                                 <entry>Swap</entry>
 139                                                 <entry>All swap partitions located on the disk the root partition is located on are enabled.</entry>
 140                                         </row>
 141                                 </tbody>
 142                         </tgroup>
 143                 </table>
 144
 145                 <para>The <filename>/home</filename> and
 146                 <filename>/srv</filename> partitions may be encrypted
 147                 in LUKS format. In this case a device mapper device is
 148                 set up under the names
 149                 <filename>/dev/mapper/home</filename> and
 150                 <filename>/dev/mapper/srv</filename>. Note that this
 151                 might create conflicts if the same partition is listed
 152                 in <filename>/etc/crypttab</filename> with a different
 153                 device mapper device name.</para>
 154
 155                 <para>Also note that
 156                 <citerefentry><refentrytitle>systemd-efi-boot-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 157                 will mount the EFI System Partition (ESP) to
 158                 <filename>/boot</filename> if not otherwise mounted.</para>
 159
 160                 <para>When using this generator in conjunction with
 161                 btrfs file systems, make sure to set the correct
 162                 default subvolumes on them, using <command>btrfs
 163                 subvolume set-default</command>.</para>
 164
 165                 <para><filename>systemd-gpt-auto-generator</filename>
 166                 implements the <ulink
 167                 url="http://www.freedesktop.org/wiki/Software/systemd/Generators">Generator
 168                 Specification</ulink>.</para>
 169         </refsect1>
 170
 171         <refsect1>
 172                 <title>See Also</title>
 173                 <para>
 174                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 175                         <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 176                         <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 177                         <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 178                         <citerefentry><refentrytitle>systemd-efi-boot-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 179                         <citerefentry><refentrytitle>systemd-cryptsetup@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 180                         <citerefentry><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 181                         <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 182                         <citerefentry><refentrytitle>btrfs</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 183                 </para>
 184         </refsect1>
 185
 186 </refentry>