man: extend systemd-gpt-auto-generator with XBOOTLDR info

This commit is contained in:
Lennart Poettering 2019-02-12 16:06:21 +01:00
parent 82dad52818
commit aa4c06844d

View file

@ -32,22 +32,18 @@
<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),
see <ulink url="http://www.uefi.org/specifications">UEFI Specification</ulink>, chapter 5.
It implements the <ulink
url="https://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 overridden, but additional
implicit dependencies might be created.</para>
<para><filename>systemd-gpt-auto-generator</filename> is a unit generator that automatically discovers
root, <filename>/home/</filename>, <filename>/srv/</filename>, the EFI System Partition, the Extended
Boot Loader Partition and swap partitions and creates mount and swap units for them, based on the
partition type GUIDs of GUID partition tables (GPT), see <ulink
url="http://www.uefi.org/specifications">UEFI Specification</ulink>, chapter 5. It implements the <ulink
url="https://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/">Discoverable Partitions
Specification</ulink>. Note that this generator has no effect on non-GPT systems, and on specific mount
points that are directories already containing files. 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 overridden, but additional implicit 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.
@ -70,11 +66,13 @@
<tgroup cols='3' align='left' colsep='1' rowsep='1'>
<colspec colname="guid" />
<colspec colname="name" />
<colspec colname="where" />
<colspec colname="explanation" />
<thead>
<row>
<entry>Partition Type GUID</entry>
<entry>Name</entry>
<entry>Mount Point</entry>
<entry>Explanation</entry>
</row>
</thead>
@ -82,48 +80,63 @@
<row>
<entry>44479540-f297-41b2-9af7-d131d5f0458a</entry>
<entry><filename>Root Partition (x86)</filename></entry>
<entry><filename>/</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><filename>/</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><filename>/</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><filename>/</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>993d8d3d-f80e-4225-855a-9daf8ed7ea97</entry>
<entry><filename>Root Partition (Itanium/IA-64)</filename></entry>
<entry><filename>/</filename></entry>
<entry>On Itanium systems, the first Itanium 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><filename>/home/</filename></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><filename>/srv/</filename></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>n/a</entry>
<entry>All swap partitions located on the disk the root partition is located on are enabled.</entry>
</row>
<row>
<entry>c12a7328-f81f-11d2-ba4b-00a0c93ec93b</entry>
<entry>EFI System Partition (ESP)</entry>
<entry><filename>/efi/</filename> or <filename>/boot/</filename></entry>
<entry>The first ESP located on the disk the root partition is located on is mounted to <filename>/boot</filename> or <filename>/efi</filename>, see below.</entry>
</row>
<row>
<entry>bc13c2ff-59e6-4262-a352-b275fd6f7172</entry>
<entry>Extended Boot Loader Partition</entry>
<entry><filename>/boot/</filename></entry>
<entry>The first Extended Boot Loader Partition is mounted to <filename>/boot</filename>, see below.</entry>
</row>
</tbody>
</tgroup>
</table>
@ -149,44 +162,49 @@
<row>
<entry><constant>GPT_FLAG_READ_ONLY</constant></entry>
<entry>0x1000000000000000</entry>
<entry><filename>/</filename>, <filename>/srv</filename>, <filename>/home</filename></entry>
<entry><filename>/</filename>, <filename>/home/</filename>, <filename>/srv/</filename>, Extended Boot Loader Partition</entry>
<entry>Partition is mounted read-only</entry>
</row>
<row>
<entry><constant>GPT_FLAG_NO_AUTO</constant></entry>
<entry>0x8000000000000000</entry>
<entry><filename>/</filename>, <filename>/srv</filename>, <filename>/home</filename></entry>
<entry><filename>/</filename>, <filename>/home/</filename>, <filename>/srv/</filename>, Extended Boot Loader Partition</entry>
<entry>Partition is not mounted automatically</entry>
</row>
<row>
<entry><constant>GPT_FLAG_NO_BLOCK_IO_PROTOCOL</constant></entry>
<entry>0x0000000000000002</entry>
<entry>ESP</entry>
<entry>EFI System Partition (ESP)</entry>
<entry>Partition is not mounted automatically</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>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) are generated on EFI systems. The ESP is mounted
to <filename>/boot</filename>, unless a mount point directory <filename>/efi</filename> exists, in which case it is
mounted there. Since this generator creates an automount unit, the mount will only be activated on-demand, when
accessed. On systems where <filename>/boot</filename> (or <filename>/efi</filename> if it exists) 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> (or <filename>/efi</filename>) mount point is non-empty, no mount units are
generated.</para>
<para>Mount and automount units for the EFI System Partition (ESP) are generated on EFI systems. The ESP
is mounted to <filename>/boot/</filename> (except if an Extended Boot Loader partition exists, see
below), unless a mount point directory <filename>/efi/</filename> exists, in which case it is mounted
there. Since this generator creates an automount unit, the mount will only be activated on-demand, when
accessed. On systems where <filename>/boot/</filename> (or <filename>/efi/</filename> if it exists) 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> (or <filename>/efi/</filename>) mount point is non-empty, no mount units
are generated.</para>
<para>If the disk contains an Extended Boot Loader partition, as defined in the <ulink
url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink>, it is made
available at <filename>/boot</filename> (by means of an automount point, similar to the ESP, see
above). If both an EFI System Partition and an Extended Boot Loader partition exist the latter is
preferably mounted to <filename>/boot/</filename>. Make sure to create both <filename>/efi/</filename>
and <filename>/boot/</filename> to ensure both partitions are mounted.</para>
<para>When using this generator in conjunction with btrfs file
systems, make sure to set the correct default subvolumes on them,