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 the partition type GUIDs of
  64                 GUID partition tables (GPT). Note that this generator
  65                 has no effect on non-GPT systems, on systems where the
  66                 units are explicitly configured (for example, listed
  67                 in
  68                 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>),
  69                 or where the mount points are non-empty.</para>
  70
  71                 <para>This generator will only look for root
  72                 partitions on the same physical disk the EFI System
  73                 Partition (ESP) is located on. It will only look for
  74                 the other partitions on the same physical disk the
  75                 root file system is located on. These partitions will
  76                 not be search on systems where the root file system is
  77                 distributed on multiple disks, for example via btrfs
  78                 RAID.</para>
  79
  80                 <para><filename>systemd-gpt-auto-generator</filename>
  81                 is useful for centralizing file system configuration
  82                 in the partition table and making manual configuration
  83                 in <filename>/etc/fstab</filename> or suchlike
  84                 unnecessary.</para>
  85
  86                 <para>This generator looks for the partitions based on
  87                 their partition type GUID. The following partition
  88                 type GUIDs are identified:</para>
  89
  90                 <table>
  91                         <title>Partition Type GUIDs</title>
  92                         <tgroup cols='3' align='left' colsep='1' rowsep='1'>
  93                                 <colspec colname="guid" />
  94                                 <colspec colname="name" />
  95                                 <colspec colname="explanation" />
  96                                 <thead>
  97                                         <row>
  98                                                 <entry>Partition Type GUID</entry>
  99                                                 <entry>Name</entry>
 100                                                 <entry>Explanation</entry>
 101                                         </row>
 102                                 </thead>
 103                                 <tbody>
 104                                         <row>
 105                                                 <entry>44479540-f297-41b2-9af7d131d5f0458a</entry>
 106                                                 <entry><filename>Root Partition (x86)</filename></entry>
 107                                                 <entry>On 32bit 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>
 108                                         </row>
 109                                         <row>
 110                                                 <entry>4f68bce3-e8cd-4db1-96e7fbcaf984b709</entry>
 111                                                 <entry><filename>Root Partition (x86-64)</filename></entry>
 112                                                 <entry>On 64bit 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>
 113                                         </row>
 114                                         <row>
 115                                                 <entry>933ac7e1-2eb4-4f13-b8440e14e2aef915</entry>
 116                                                 <entry>Home Partition</entry>
 117                                                 <entry>The first home partition on the disk the root partition is located on is mounted to <filename>/home</filename>.</entry>
 118                                         </row>
 119                                         <row>
 120                                                 <entry>3b8f8425-20e0-4f3b-907f1a25a76f98e8</entry>
 121                                                 <entry>Server Data Partition</entry>
 122                                                 <entry>The first server data partition on the disk the root partition is located on is mounted to <filename>/srv</filename>.</entry>
 123                                         </row>
 124                                         <row>
 125                                                 <entry>0657fd6d-a4ab-43c4-84e50933c84b4f4f</entry>
 126                                                 <entry>Swap</entry>
 127                                                 <entry>All swap partitions located on the disk the root partition is located on are enabled.</entry>
 128                                         </row>
 129                                 </tbody>
 130                         </tgroup>
 131                 </table>
 132
 133                 <para>The <filename>/home</filename> and
 134                 <filename>/srv</filename> partitions may be encrypted
 135                 in LUKS format. In this case a device mapper device is
 136                 set up under the names
 137                 <filename>/dev/mapper/home</filename> and
 138                 <filename>/dev/mapper/srv</filename>. Note that this
 139                 might create conflicts if the same partition is listed
 140                 in <filename>/etc/crypttab</filename> with a different
 141                 device mapper device name.</para>
 142
 143                 <para>Also note that
 144                 <citerefentry><refentrytitle>systemd-efi-boot-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 145                 will mount the EFI System Partition (ESP) to
 146                 <filename>/boot</filename> if not otherwise mounted.</para>
 147
 148                 <para>When using this generator in conjunction with
 149                 btrfs file systems make sure to set the correct
 150                 default subvolumes on them, using <command>btrfs
 151                 subvolume set-default</command>.</para>
 152
 153                 <para><filename>systemd-gpt-auto-generator</filename>
 154                 implements the <ulink
 155                 url="http://www.freedesktop.org/wiki/Software/systemd/Generators">generator
 156                 specification</ulink>.</para>
 157         </refsect1>
 158
 159         <refsect1>
 160                 <title>See Also</title>
 161                 <para>
 162                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 163                         <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 164                         <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 165                         <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 166                         <citerefentry><refentrytitle>systemd-efi-boot-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 167                         <citerefentry><refentrytitle>systemd-cryptsetup@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 168                         <citerefentry><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 169                         <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 170                         <citerefentry><refentrytitle>btrfs</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 171                 </para>
 172         </refsect1>
 173
 174 </refentry>