nixpkgs/nixos/doc/manual/development/building-parts.xml
Wilhelm Schuster 5f8d14546b Manual: Explicitly mark commands that require to be run as root (#15589)
* manual: Mark commands that require root

Mark every command that requires to be run as root by prefixing them
with '#' instead of '$'.

* manual: Add note about commands that require root
2016-06-01 15:23:32 +01:00

114 lines
3.6 KiB
XML
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<chapter xmlns="http://docbook.org/ns/docbook"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:xi="http://www.w3.org/2001/XInclude"
version="5.0"
xml:id="sec-building-parts">
<title>Building Specific Parts of NixOS</title>
<para>With the command <command>nix-build</command>, you can build
specific parts of your NixOS configuration. This is done as follows:
<screen>
$ cd <replaceable>/path/to/nixpkgs/nixos</replaceable>
$ nix-build -A config.<replaceable>option</replaceable></screen>
where <replaceable>option</replaceable> is a NixOS option with type
“derivation” (i.e. something that can be built). Attributes of
interest include:
<variablelist>
<varlistentry>
<term><varname>system.build.toplevel</varname></term>
<listitem>
<para>The top-level option that builds the entire NixOS system.
Everything else in your configuration is indirectly pulled in by
this option. This is what <command>nixos-rebuild</command>
builds and what <filename>/run/current-system</filename> points
to afterwards.</para>
<para>A shortcut to build this is:
<screen>
$ nix-build -A system</screen>
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>system.build.manual.manual</varname></term>
<listitem><para>The NixOS manual.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>system.build.etc</varname></term>
<listitem><para>A tree of symlinks that form the static parts of
<filename>/etc</filename>.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>system.build.initialRamdisk</varname></term>
<term><varname>system.build.kernel</varname></term>
<listitem>
<para>The initial ramdisk and kernel of the system. This allows
a quick way to test whether the kernel and the initial ramdisk
boot correctly, by using QEMUs <option>-kernel</option> and
<option>-initrd</option> options:
<screen>
$ nix-build -A config.system.build.initialRamdisk -o initrd
$ nix-build -A config.system.build.kernel -o kernel
$ qemu-system-x86_64 -kernel ./kernel/bzImage -initrd ./initrd/initrd -hda /dev/null
</screen>
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>system.build.nixos-rebuild</varname></term>
<term><varname>system.build.nixos-install</varname></term>
<term><varname>system.build.nixos-generate-config</varname></term>
<listitem>
<para>These build the corresponding NixOS commands.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><varname>systemd.units.<replaceable>unit-name</replaceable>.unit</varname></term>
<listitem>
<para>This builds the unit with the specified name. Note that
since unit names contain dots
(e.g. <literal>httpd.service</literal>), you need to put them
between quotes, like this:
<screen>
$ nix-build -A 'config.systemd.units."httpd.service".unit'
</screen>
You can also test individual units, without rebuilding the whole
system, by putting them in
<filename>/run/systemd/system</filename>:
<screen>
$ cp $(nix-build -A 'config.systemd.units."httpd.service".unit')/httpd.service \
/run/systemd/system/tmp-httpd.service
# systemctl daemon-reload
# systemctl start tmp-httpd.service
</screen>
Note that the unit must not have the same name as any unit in
<filename>/etc/systemd/system</filename> since those take
precedence over <filename>/run/systemd/system</filename>.
Thats why the unit is installed as
<filename>tmp-httpd.service</filename> here.</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</chapter>