nixpkgs/nixos/doc/manual/administration/declarative-containers.xml
2015-12-10 19:17:33 +01:00

61 lines
2.2 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.

<section 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-declarative-containers">
<title>Declarative Container Specification</title>
<para>You can also specify containers and their configuration in the
hosts <filename>configuration.nix</filename>. For example, the
following specifies that there shall be a container named
<literal>database</literal> running PostgreSQL:
<programlisting>
containers.database =
{ config =
{ config, pkgs, ... }:
{ services.postgresql.enable = true;
services.postgresql.package = pkgs.postgresql92;
};
};
</programlisting>
If you run <literal>nixos-rebuild switch</literal>, the container will
be built. If the container was already running, it will be
updated in place, without rebooting. The container can be configured to
start automatically by setting <literal>containers.database.autoStart = true</literal>
in its configuration.</para>
<para>By default, declarative containers share the network namespace
of the host, meaning that they can listen on (privileged)
ports. However, they cannot change the network configuration. You can
give a container its own network as follows:
<programlisting>
containers.database =
{ privateNetwork = true;
hostAddress = "192.168.100.10";
localAddress = "192.168.100.11";
};
</programlisting>
This gives the container a private virtual Ethernet interface with IP
address <literal>192.168.100.11</literal>, which is hooked up to a
virtual Ethernet interface on the host with IP address
<literal>192.168.100.10</literal>. (See the next section for details
on container networking.)</para>
<para>To disable the container, just remove it from
<filename>configuration.nix</filename> and run <literal>nixos-rebuild
switch</literal>. Note that this will not delete the root directory of
the container in <literal>/var/lib/containers</literal>. Containers can be
destroyed using the imperative method: <literal>nixos-container destroy
foo</literal>.</para>
<para>Declarative containers can be started and stopped using the
corresponding systemd service, e.g. <literal>systemctl start
container@database</literal>.</para>
</section>