mirror of
https://github.com/systemd/systemd.git
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597c6cc119
Some ambiguity (e.g., same-named man pages in multiple volumes)
makes it impossible to fully automate this, but the following
Python snippet (run inside the man/ directory of the systemd repo)
helped to generate the sed command lines (which were subsequently
manually reviewed, run and the false positives reverted):
from pathlib import Path
import lxml
from lxml import etree as ET
man2vol: dict[str, str] = {}
man2citerefs: dict[str, list] = {}
for file in Path(".").glob("*.xml"):
tree = ET.parse(file, lxml.etree.XMLParser(recover=True))
meta = tree.find("refmeta")
if meta is not None:
title = meta.findtext("refentrytitle")
if title is not None:
vol = meta.findtext("manvolnum")
if vol is not None:
man2vol[title] = vol
citerefs = list(tree.iter("citerefentry"))
if citerefs:
man2citerefs[title] = citerefs
for man, refs in man2citerefs.items():
for ref in refs:
title = ref.findtext("refentrytitle")
if title is not None:
has = ref.findtext("manvolnum")
try:
should_have = man2vol[title]
except KeyError: # Non-systemd man page reference? Ignore.
continue
if has != should_have:
print(
f"sed -i '\\|<citerefentry><refentrytitle>{title}"
f"</refentrytitle><manvolnum>{has}</manvolnum>"
f"</citerefentry>|s|<manvolnum>{has}</manvolnum>|"
f"<manvolnum>{should_have}</manvolnum>|' {man}.xml"
)
485 lines
29 KiB
XML
485 lines
29 KiB
XML
<?xml version='1.0'?> <!--*-nxml-*-->
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
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<refentry id="systemd-sysext" conditional='ENABLE_SYSEXT'
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xmlns:xi="http://www.w3.org/2001/XInclude">
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<refentryinfo>
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<title>systemd-sysext</title>
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<productname>systemd</productname>
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</refentryinfo>
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<refmeta>
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<refentrytitle>systemd-sysext</refentrytitle>
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<manvolnum>8</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>systemd-sysext</refname>
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<refname>systemd-sysext.service</refname>
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<refname>systemd-confext</refname>
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<refname>systemd-confext.service</refname>
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<refpurpose>Activates System Extension Images</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<cmdsynopsis>
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<command>systemd-sysext</command>
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<arg choice="opt" rep="repeat">OPTIONS</arg>
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<arg choice="plain">COMMAND</arg>
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</cmdsynopsis>
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<para><filename>systemd-sysext.service</filename></para>
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<cmdsynopsis>
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<command>systemd-confext</command>
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<arg choice="opt" rep="repeat">OPTIONS</arg>
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<arg choice="plain">COMMAND</arg>
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</cmdsynopsis>
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<para><filename>systemd-confext.service</filename></para>
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</refsynopsisdiv>
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<refsect1>
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<title>Description</title>
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<para><command>systemd-sysext</command> activates/deactivates system extension images. System extension
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images may – dynamically at runtime — extend the <filename>/usr/</filename> and
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<filename>/opt/</filename> directory hierarchies with additional files. This is particularly useful on
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immutable system images where a <filename>/usr/</filename> and/or <filename>/opt/</filename> hierarchy
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residing on a read-only file system shall be extended temporarily at runtime without making any
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persistent modifications.</para>
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<para>System extension images should contain files and directories similar in fashion to regular
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operating system tree. When one or more system extension images are activated, their
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<filename>/usr/</filename> and <filename>/opt/</filename> hierarchies are combined via
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<literal>overlayfs</literal> with the same hierarchies of the host OS, and the host
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<filename>/usr/</filename> and <filename>/opt/</filename> overmounted with it ("merging"). When they are
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deactivated, the mount point is disassembled — again revealing the unmodified original host version of
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the hierarchy ("unmerging"). Merging thus makes the extension's resources suddenly appear below the
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<filename>/usr/</filename> and <filename>/opt/</filename> hierarchies as if they were included in the
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base OS image itself. Unmerging makes them disappear again, leaving in place only the files that were
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shipped with the base OS image itself.</para>
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<para>Files and directories contained in the extension images outside of the <filename>/usr/</filename>
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and <filename>/opt/</filename> hierarchies are <emphasis>not</emphasis> merged, and hence have no effect
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when included in a system extension image. In particular, files in the <filename>/etc/</filename> and
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<filename>/var/</filename> included in a system extension image will <emphasis>not</emphasis> appear in
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the respective hierarchies after activation.</para>
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<para>System extension images are strictly read-only by default. On mutable host file systems,
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<filename>/usr/</filename> and <filename>/opt/</filename> hierarchies become read-only while extensions
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are merged, unless mutability is enabled. Mutability may be enabled via the <option>--mutable=</option>
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option; see "Mutability" below for more information.</para>
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<para>System extensions are supposed to be purely additive, i.e. they are supposed to include only files
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that do not exist in the underlying basic OS image. However, the underlying mechanism (overlayfs) also
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allows overlaying or removing files, but it is recommended not to make use of this.</para>
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<para>System extension images may be provided in the following formats:</para>
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<orderedlist>
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<listitem><para>Plain directories or btrfs subvolumes containing the OS tree</para></listitem>
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<listitem><para>Disk images with a GPT disk label, following the <ulink
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url="https://uapi-group.org/specifications/specs/discoverable_partitions_specification">Discoverable Partitions Specification</ulink></para></listitem>
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<listitem><para>Disk images lacking a partition table, with a naked Linux file system (e.g. erofs,
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squashfs or ext4)</para></listitem>
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</orderedlist>
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<para>These image formats are the same ones that
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<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
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supports via its <option>--directory=</option>/<option>--image=</option> switches and those that the
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service manager supports via <option>RootDirectory=</option>/<option>RootImage=</option>. Similar to
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them they may optionally carry Verity authentication information.</para>
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<para>System extensions are searched for in the directories
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<filename>/etc/extensions/</filename>, <filename>/run/extensions/</filename> and
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<filename>/var/lib/extensions/</filename>. The first two listed directories are not suitable for
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carrying large binary images, however are still useful for carrying symlinks to them. The primary place
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for installing system extensions is <filename>/var/lib/extensions/</filename>. Any directories found in
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these search directories are considered directory based extension images; any files with the
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<filename>.raw</filename> suffix are considered disk image based extension images. When invoked in the
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initrd, the additional directory <filename>/.extra/sysext/</filename> is included in the directories that
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are searched for extension images. Note however, that by default a tighter image policy applies to images
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found there, though, see below. This directory is populated by
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<citerefentry><refentrytitle>systemd-stub</refentrytitle><manvolnum>7</manvolnum></citerefentry> with
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extension images found in the system's EFI System Partition.</para>
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<para>During boot OS extension images are activated automatically, if the
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<filename>systemd-sysext.service</filename> is enabled. Note that this service runs only after the
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underlying file systems where system extensions may be located have been mounted. This means they are not
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suitable for shipping resources that are processed by subsystems running in earliest boot. Specifically,
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OS extension images are not suitable for shipping system services or
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<citerefentry><refentrytitle>systemd-sysusers</refentrytitle><manvolnum>8</manvolnum></citerefentry>
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definitions. See the <ulink url="https://systemd.io/PORTABLE_SERVICES">Portable Services</ulink> page
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for a simple mechanism for shipping system services in disk images, in a similar fashion to OS
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extensions. Note the different isolation on these two mechanisms: while system extension directly extend
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the underlying OS image with additional files that appear in a way very similar to as if they were
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shipped in the OS image itself and thus imply no security isolation, portable services imply service
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level sandboxing in one way or another. The <filename>systemd-sysext.service</filename> service is
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guaranteed to finish start-up before <filename>basic.target</filename> is reached; i.e. at the time
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regular services initialize (those which do not use <varname>DefaultDependencies=no</varname>), the files
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and directories system extensions provide are available in <filename>/usr/</filename> and
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<filename>/opt/</filename> and may be accessed.</para>
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<para>Note that there is no concept of enabling/disabling installed system extension images: all
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installed extension images are automatically activated at boot. However, you can place an empty directory
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named like the extension (no <filename>.raw</filename>) in <filename>/etc/extensions/</filename> to "mask"
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an extension with the same name in a system folder with lower precedence.</para>
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<para>A simple mechanism for version compatibility is enforced: a system extension image must carry a
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<filename>/usr/lib/extension-release.d/extension-release.<replaceable>NAME</replaceable></filename>
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file, which must match its image name, that is compared with the host <filename>os-release</filename>
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file: the contained <varname>ID=</varname> fields have to match unless <literal>_any</literal> is set
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for the extension. If the extension <varname>ID=</varname> is not <literal>_any</literal>, the
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<varname>SYSEXT_LEVEL=</varname> field (if defined) has to match. If the latter is not defined, the
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<varname>VERSION_ID=</varname> field has to match instead. If the extension defines the
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<varname>ARCHITECTURE=</varname> field and the value is not <literal>_any</literal> it has to match the kernel's
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architecture reported by <citerefentry><refentrytitle>uname</refentrytitle><manvolnum>2</manvolnum></citerefentry>
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but the used architecture identifiers are the same as for <varname>ConditionArchitecture=</varname>
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described in <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
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<varname>EXTENSION_RELOAD_MANAGER=</varname> can be set to 1 if the extension requires a service manager reload after application
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of the extension. Note that for the reasons mentioned earlier:
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<ulink url="https://systemd.io/PORTABLE_SERVICES">Portable Services</ulink> remain
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the recommended way to ship system services.
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System extensions should not ship a <filename>/usr/lib/os-release</filename> file (as that would be merged
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into the host <filename>/usr/</filename> tree, overriding the host OS version data, which is not desirable).
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The <filename>extension-release</filename> file follows the same format and semantics, and carries the same
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content, as the <filename>os-release</filename> file of the OS, but it describes the resources carried
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in the extension image.</para>
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<para>The <command>systemd-confext</command> concept follows the same principle as the
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<citerefentry><refentrytitle>systemd-sysext</refentrytitle><manvolnum>8</manvolnum></citerefentry>
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functionality but instead of working on <filename>/usr</filename> and <filename>/opt</filename>,
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<command>confext</command> will extend only <filename>/etc</filename>. Files and directories contained
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in the confext images outside of the <filename>/etc/</filename> hierarchy are <emphasis>not</emphasis>
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merged, and hence have no effect when included in the image. Formats for these images are of the
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same as sysext images. The merged hierarchy will be mounted with <literal>nosuid</literal> and
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(if not disabled via <option>--noexec=false</option>) <literal>noexec</literal>.</para>
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<para>Just like sysexts, confexts are strictly read-only by default. Merging confexts on mutable host
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file systems will result in <filename>/etc/</filename> becoming read-only. As with sysexts, mutability
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can be enabled via the <option>--mutable=</option> option. Refer to "Mutability" below for more
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information.</para>
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<para>Confexts are looked for in the directories <filename>/run/confexts/</filename>,
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<filename>/var/lib/confexts/</filename>, <filename>/usr/lib/confexts/</filename> and
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<filename>/usr/local/lib/confexts/</filename>. The first listed directory is not suitable for
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carrying large binary images, however is still useful for carrying symlinks to them. The primary place
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for installing configuration extensions is <filename>/var/lib/confexts/</filename>. Any directories found
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in these search directories are considered directory based confext images; any files with the
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<filename>.raw</filename> suffix are considered disk image based confext images.</para>
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<para>Again, just like sysext images, the confext images will contain a
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<filename>/etc/extension-release.d/extension-release.<replaceable>NAME</replaceable></filename>
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file, which must match the image name (with the usual escape hatch of
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the <varname>user.extension-release.strict</varname>
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<citerefentry project='man-pages'><refentrytitle>xattr</refentrytitle><manvolnum>7</manvolnum></citerefentry>),
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and again with content being one or more of <varname>ID=</varname>, <varname>VERSION_ID=</varname>, and
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<varname>CONFEXT_LEVEL</varname>. Confext images will then be checked and matched against the base OS
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layer.</para>
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</refsect1>
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<refsect1>
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<title>Uses</title>
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<para>The primary use case for system images are immutable environments where debugging and development
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tools shall optionally be made available, but not included in the immutable base OS image itself (e.g.
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<citerefentry project='man-pages'><refentrytitle>strace</refentrytitle><manvolnum>1</manvolnum></citerefentry>
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and
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<citerefentry project='man-pages'><refentrytitle>gdb</refentrytitle><manvolnum>1</manvolnum></citerefentry>
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shall be an optionally installable addition in order to make debugging/development easier). System
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extension images should not be misunderstood as a generic software packaging framework, as no dependency
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scheme is available: system extensions should carry all files they need themselves, except for those
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already shipped in the underlying host system image. Typically, system extension images are built at the
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same time as the base OS image — within the same build system.</para>
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<para>Another use case for the system extension concept is temporarily overriding OS supplied resources
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with newer ones, for example to install a locally compiled development version of some low-level
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component over the immutable OS image without doing a full OS rebuild or modifying the nominally
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immutable image. (e.g. "install" a locally built package with <command>DESTDIR=/var/lib/extensions/mytest
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make install && systemd-sysext refresh</command>, making it available in
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<filename>/usr/</filename> as if it was installed in the OS image itself.) This case works regardless if
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the underlying host <filename>/usr/</filename> is managed as immutable disk image or is a traditional
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package manager controlled (i.e. writable) tree.</para>
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<para>With systemd-confext one can perform runtime reconfiguration of OS services.
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Sometimes, there is a need to swap certain configuration parameter values or restart only a specific
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service without deployment of new code or a complete OS deployment. In other words, we want to be able
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to tie the most frequently configured options to runtime updateable flags that can be changed without a
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system reboot. This will help reduce servicing times when there is a need for changing the OS configuration.
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It also provides a reliable tool for managing configuration because all old configuration files disappear when
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the systemd-confext image is removed.</para></refsect1>
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<refsect1>
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<title>Mutability</title>
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<para>By default, merging system extensions on mutable host file systems will render <filename>/usr/</filename>
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and <filename>/opt/</filename> hierarchies read-only. Merging configuration extensions will have the same
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effect on <filename>/etc/</filename>. Mutable mode allows writes to these locations when extensions are
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merged.</para>
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<para>The following modes are supported:
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<orderedlist>
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<listitem><para><option>disabled</option>: Force immutable mode even if write routing directories exist
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below <filename>/var/lib/extensions.mutable/</filename>. This is the default.</para></listitem>
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<listitem><para><option>auto</option>: Automatic mode. Mutability is disabled by default and only
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enabled if a corresponding write routing directory exists below
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<filename>/var/lib/extensions.mutable/</filename>.</para></listitem>
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<listitem><para><option>enabled</option>: Force mutable mode and automatically create write routing
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directories below <filename>/var/lib/extensions.mutable/</filename> when required.</para></listitem>
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<listitem><para><option>import</option>: Force immutable mode like <option>disabled</option> above, but
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merge the contents of directories below <filename>/var/lib/extensions.mutable/</filename> into the host
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file system.</para></listitem>
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<listitem><para><option>ephemeral</option>: Force mutable mode like <option>enabled</option> above, but
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instead of using write routing directory below <filename>/var/lib/extensions.mutable/</filename>,
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<command>systemd-sysext</command> will use empty ephemeral directories. This means that the
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modifications made in the merged hierarchies will be gone when the hierarchies are
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unmerged.</para></listitem>
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<listitem><para><option>ephemeral-import</option>: Force mutable mode like <option>ephemeral</option>
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above, but instead of ignoring the contents of write routing directories under
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<filename>/var/lib/extensions.mutable/</filename>, merge them into the host file system, like
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<option>import</option> does.</para></listitem>
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</orderedlist>
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See "Options" below on specifying modes using the <option>--mutable=</option> command line option.</para>
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<para>With exception of the ephemeral mode, the mutable mode routes writes to subdirectories in
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<filename>/var/lib/extensions.mutable/</filename>.
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<simplelist type="horiz">
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<member>Writes to <filename>/usr/</filename> are directed to <filename>/var/lib/extensions.mutable/usr/</filename></member>,
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<member>writes to <filename>/opt/</filename> are directed to <filename>/var/lib/extensions.mutable/opt/</filename>, and</member>
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<member>writes to <filename>/etc/</filename> land in <filename>/var/lib/extensions.mutable/etc/</filename>.</member>
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</simplelist></para>
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<para>If <filename>usr/</filename>, <filename>opt/</filename>, or <filename>etc/</filename>
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in <filename>/var/lib/extensions.mutable/</filename> are symlinks, then writes are directed to the
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symlinks' targets.
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Consequently, to retain mutability of a host file system, create symlinks
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<simplelist type="horiz">
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<member><filename>/var/lib/extensions.mutable/etc/</filename> → <filename>/etc/</filename></member>
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<member><filename>/var/lib/extensions.mutable/usr/</filename> → <filename>/usr/</filename></member>
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<member><filename>/var/lib/extensions.mutable/opt/</filename> → <filename>/opt/</filename></member>
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</simplelist>
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to route writes back to the original base directory hierarchy.</para>
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<para>Alternatively, a temporary file system may be mounted to
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<filename>/var/lib/extensions.mutable/</filename>, or symlinks in
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<filename>/var/lib/extensions.mutable/</filename> may point to sub-directories on a temporary file system
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(e.g. below <filename>/tmp/</filename>) to only allow ephemeral changes. Note that this is not the same
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as ephemeral mode, because the temporary file system will still exist after unmerging.</para>
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<xi:include href="version-info.xml" xpointer="v256"/>
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</refsect1>
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<refsect1>
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<title>Commands</title>
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<para>The following commands are understood by both the sysext and confext concepts:</para>
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<variablelist>
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<varlistentry>
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<term><option>status</option></term>
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<listitem><para>When invoked without any command verb, or when <option>status</option> is specified
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the current merge status is shown, separately (for both <filename>/usr/</filename> and
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<filename>/opt/</filename> of sysext and for <filename>/etc/</filename> of confext).</para>
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<xi:include href="version-info.xml" xpointer="v248"/></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>merge</option></term>
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<listitem><para>Merges all currently installed system extension images into
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<filename>/usr/</filename> and <filename>/opt/</filename>, by overmounting these hierarchies with an
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<literal>overlayfs</literal> file system combining the underlying hierarchies with those included in
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the extension images. This command will fail if the hierarchies are already merged. For confext, the merge
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happens into the <filename>/etc/</filename> directory instead.</para>
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<xi:include href="version-info.xml" xpointer="v248"/></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>unmerge</option></term>
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<listitem><para>Unmerges all currently installed system extension images from
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<filename>/usr/</filename> and <filename>/opt/</filename> for sysext and <filename>/etc/</filename>,
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for confext, by unmounting the <literal>overlayfs</literal> file systems created by <option>merge</option>
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prior.</para>
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<xi:include href="version-info.xml" xpointer="v248"/></listitem>
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</varlistentry>
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<varlistentry>
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<term><option>refresh</option></term>
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<listitem><para>A combination of <option>unmerge</option> and <option>merge</option>: if already
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mounted the existing <literal>overlayfs</literal> instance is unmounted temporarily, and then
|
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replaced by a new version. This command is useful after installing/removing system extension images,
|
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in order to update the <literal>overlayfs</literal> file system accordingly. If no system extensions
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are installed when this command is executed, the equivalent of <option>unmerge</option> is executed,
|
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without establishing any new <literal>overlayfs</literal> instance.
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Note that currently there's a brief moment where neither the old nor the new <literal>overlayfs</literal>
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file system is mounted. This implies that all resources supplied by a system extension will briefly
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disappear — even if it exists continuously during the refresh operation.</para>
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||
|
||
<xi:include href="version-info.xml" xpointer="v248"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>list</option></term>
|
||
|
||
<listitem><para>A brief list of installed extension images is shown.</para>
|
||
|
||
<xi:include href="version-info.xml" xpointer="v248"/></listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="help" />
|
||
<xi:include href="standard-options.xml" xpointer="version" />
|
||
</variablelist>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Options</title>
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>--root=</option></term>
|
||
|
||
<listitem><para>Operate relative to the specified root directory, i.e. establish the
|
||
<literal>overlayfs</literal> mount not on the top-level host <filename>/usr/</filename> and
|
||
<filename>/opt/</filename> hierarchies for sysext or <filename>/etc/</filename> for confext,
|
||
but below some specified root directory.</para>
|
||
|
||
<xi:include href="version-info.xml" xpointer="v248"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--force</option></term>
|
||
|
||
<listitem><para>When merging system extensions into <filename>/usr/</filename> and
|
||
<filename>/opt/</filename> for sysext and <filename>/etc/</filename> for confext,
|
||
ignore version incompatibilities, i.e. force merging regardless of
|
||
whether the version information included in the images matches the host or not.</para>
|
||
|
||
<xi:include href="version-info.xml" xpointer="v248"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--image-policy=<replaceable>policy</replaceable></option></term>
|
||
|
||
<listitem><para>Takes an image policy string as argument, as per
|
||
<citerefentry><refentrytitle>systemd.image-policy</refentrytitle><manvolnum>7</manvolnum></citerefentry>. The
|
||
policy is enforced when operating on system extension disk images. If not specified defaults to
|
||
<literal>root=verity+signed+encrypted+unprotected+absent:usr=verity+signed+encrypted+unprotected+absent</literal>
|
||
for system extensions, i.e. only the root and <filename>/usr/</filename> file systems in the image
|
||
are used. For configuration extensions defaults to
|
||
<literal>root=verity+signed+encrypted+unprotected+absent</literal>. When run in the initrd and
|
||
operating on a system extension image stored in the <filename>/.extra/sysext/</filename> directory a
|
||
slightly stricter policy is used by default: <literal>root=signed+absent:usr=signed+absent</literal>,
|
||
see above for details.</para>
|
||
|
||
<xi:include href="version-info.xml" xpointer="v254"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--mutable=<replaceable>BOOL</replaceable>|<replaceable>auto</replaceable>|<replaceable>import</replaceable></option></term>
|
||
<listitem><para>Set mutable mode.</para>
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>no</option></term>
|
||
<listitem><para>force immutable mode even with write routing directories present.
|
||
This is the default.</para>
|
||
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>auto</option></term>
|
||
<listitem><para>enable mutable mode individually for <filename>/usr/</filename>,
|
||
<filename>/opt/</filename>, and <filename>/etc/</filename> if write routing sub-directories
|
||
or symlinks are present in <filename>/var/lib/extensions.mutable/</filename>; disable otherwise.
|
||
See "Mutability" above for more information on write routing.</para>
|
||
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>yes</option></term>
|
||
<listitem><para>force mutable mode. Write routing directories will be created in
|
||
<filename>/var/lib/extensions.mutable/</filename> if not present.</para>
|
||
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>import</option></term>
|
||
<listitem><para>immutable mode, but with contents of write routing directories in
|
||
<filename>/var/lib/extensions.mutable/</filename> also merged into the host file system.</para>
|
||
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>ephemeral</option></term>
|
||
<listitem><para>force mutable mode, but with contents of write routing directories in
|
||
<filename>/var/lib/extensions.mutable/</filename> being ignored, and modifications of the host
|
||
file system being discarded after unmerge.</para>
|
||
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>ephemeral-import</option></term>
|
||
<listitem><para>force mutable mode, with contents of write routing directories in
|
||
<filename>/var/lib/extensions.mutable/</filename> being merged into the host file system, but
|
||
with the modifications made to the host file system being discarded after unmerge.</para>
|
||
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
|
||
</varlistentry>
|
||
</variablelist>
|
||
|
||
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--noexec=<replaceable>BOOL</replaceable></option></term>
|
||
|
||
<listitem><para>When merging configuration extensions into <filename>/etc/</filename> the
|
||
<literal>MS_NOEXEC</literal> mount flag is used by default. This option can be used to disable
|
||
it.</para>
|
||
|
||
<xi:include href="version-info.xml" xpointer="v254"/></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--no-reload</option></term>
|
||
|
||
<listitem>
|
||
<para>When used with <command>merge</command>,
|
||
<command>unmerge</command> or <command>refresh</command>, do not reload daemon
|
||
after executing the changes even if an extension that is applied requires a reload via the
|
||
<varname>EXTENSION_RELOAD_MANAGER=</varname> set to 1.</para>
|
||
|
||
<xi:include href="version-info.xml" xpointer="v255"/>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<xi:include href="standard-options.xml" xpointer="no-pager" />
|
||
<xi:include href="standard-options.xml" xpointer="no-legend" />
|
||
<xi:include href="standard-options.xml" xpointer="json" />
|
||
</variablelist>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>Exit status</title>
|
||
|
||
<para>On success, 0 is returned.</para>
|
||
</refsect1>
|
||
|
||
<refsect1>
|
||
<title>See Also</title>
|
||
<para><simplelist type="inline">
|
||
<member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
|
||
<member><citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
|
||
<member><citerefentry><refentrytitle>systemd-stub</refentrytitle><manvolnum>7</manvolnum></citerefentry></member>
|
||
<member><citerefentry><refentrytitle>importctl</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
|
||
</simplelist></para>
|
||
</refsect1>
|
||
|
||
</refentry>
|