84b1c0c481
Since some time Nixos has firewall enabled by default, so update example. Also, remove newline escaping (it isn't needed). Closes https://github.com/NixOS/nixpkgs/issues/25174
134 lines
3.9 KiB
XML
134 lines
3.9 KiB
XML
<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-imperative-containers">
|
||
|
||
<title>Imperative Container Management</title>
|
||
|
||
<para>We’ll cover imperative container management using
|
||
<command>nixos-container</command> first.
|
||
Be aware that container management is currently only possible
|
||
as <literal>root</literal>.</para>
|
||
|
||
<para>You create a container with
|
||
identifier <literal>foo</literal> as follows:
|
||
|
||
<screen>
|
||
# nixos-container create foo
|
||
</screen>
|
||
|
||
This creates the container’s root directory in
|
||
<filename>/var/lib/containers/foo</filename> and a small configuration
|
||
file in <filename>/etc/containers/foo.conf</filename>. It also builds
|
||
the container’s initial system configuration and stores it in
|
||
<filename>/nix/var/nix/profiles/per-container/foo/system</filename>. You
|
||
can modify the initial configuration of the container on the command
|
||
line. For instance, to create a container that has
|
||
<command>sshd</command> running, with the given public key for
|
||
<literal>root</literal>:
|
||
|
||
<screen>
|
||
# nixos-container create foo --config '
|
||
services.openssh.enable = true;
|
||
users.extraUsers.root.openssh.authorizedKeys.keys = ["ssh-dss AAAAB3N…"];
|
||
'
|
||
</screen>
|
||
|
||
</para>
|
||
|
||
<para>Creating a container does not start it. To start the container,
|
||
run:
|
||
|
||
<screen>
|
||
# nixos-container start foo
|
||
</screen>
|
||
|
||
This command will return as soon as the container has booted and has
|
||
reached <literal>multi-user.target</literal>. On the host, the
|
||
container runs within a systemd unit called
|
||
<literal>container@<replaceable>container-name</replaceable>.service</literal>.
|
||
Thus, if something went wrong, you can get status info using
|
||
<command>systemctl</command>:
|
||
|
||
<screen>
|
||
# systemctl status container@foo
|
||
</screen>
|
||
|
||
</para>
|
||
|
||
<para>If the container has started succesfully, you can log in as
|
||
root using the <command>root-login</command> operation:
|
||
|
||
<screen>
|
||
# nixos-container root-login foo
|
||
[root@foo:~]#
|
||
</screen>
|
||
|
||
Note that only root on the host can do this (since there is no
|
||
authentication). You can also get a regular login prompt using the
|
||
<command>login</command> operation, which is available to all users on
|
||
the host:
|
||
|
||
<screen>
|
||
# nixos-container login foo
|
||
foo login: alice
|
||
Password: ***
|
||
</screen>
|
||
|
||
With <command>nixos-container run</command>, you can execute arbitrary
|
||
commands in the container:
|
||
|
||
<screen>
|
||
# nixos-container run foo -- uname -a
|
||
Linux foo 3.4.82 #1-NixOS SMP Thu Mar 20 14:44:05 UTC 2014 x86_64 GNU/Linux
|
||
</screen>
|
||
|
||
</para>
|
||
|
||
<para>There are several ways to change the configuration of the
|
||
container. First, on the host, you can edit
|
||
<literal>/var/lib/container/<replaceable>name</replaceable>/etc/nixos/configuration.nix</literal>,
|
||
and run
|
||
|
||
<screen>
|
||
# nixos-container update foo
|
||
</screen>
|
||
|
||
This will build and activate the new configuration. You can also
|
||
specify a new configuration on the command line:
|
||
|
||
<screen>
|
||
# nixos-container update foo --config '
|
||
services.httpd.enable = true;
|
||
services.httpd.adminAddr = "foo@example.org";
|
||
networking.firewall.allowedTCPPorts = [ 80 ];
|
||
'
|
||
|
||
# curl http://$(nixos-container show-ip foo)/
|
||
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">…
|
||
</screen>
|
||
|
||
However, note that this will overwrite the container’s
|
||
<filename>/etc/nixos/configuration.nix</filename>.</para>
|
||
|
||
<para>Alternatively, you can change the configuration from within the
|
||
container itself by running <command>nixos-rebuild switch</command>
|
||
inside the container. Note that the container by default does not have
|
||
a copy of the NixOS channel, so you should run <command>nix-channel
|
||
--update</command> first.</para>
|
||
|
||
<para>Containers can be stopped and started using
|
||
<literal>nixos-container stop</literal> and <literal>nixos-container
|
||
start</literal>, respectively, or by using
|
||
<command>systemctl</command> on the container’s service unit. To
|
||
destroy a container, including its file system, do
|
||
|
||
<screen>
|
||
# nixos-container destroy foo
|
||
</screen>
|
||
|
||
</para>
|
||
|
||
</section>
|