Merge pull request #128937 from bobby285271/pr8
nixos/doc: convert "Chapter 55. Container Management" to CommonMark
This commit is contained in:
Jörg Thalheim
GitHub
commit
0d789e992f
10 changed files with 455 additions and 245 deletions
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@ -0,0 +1,44 @@
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# Container Networking {#sec-container-networking}
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When you create a container using `nixos-container create`, it gets it
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own private IPv4 address in the range `10.233.0.0/16`. You can get the
|
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container's IPv4 address as follows:
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|
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```ShellSession
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# nixos-container show-ip foo
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10.233.4.2
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$ ping -c1 10.233.4.2
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64 bytes from 10.233.4.2: icmp_seq=1 ttl=64 time=0.106 ms
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```
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Networking is implemented using a pair of virtual Ethernet devices. The
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network interface in the container is called `eth0`, while the matching
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interface in the host is called `ve-container-name` (e.g., `ve-foo`).
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The container has its own network namespace and the `CAP_NET_ADMIN`
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capability, so it can perform arbitrary network configuration such as
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setting up firewall rules, without affecting or having access to the
|
||||
host's network.
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By default, containers cannot talk to the outside network. If you want
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that, you should set up Network Address Translation (NAT) rules on the
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host to rewrite container traffic to use your external IP address. This
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can be accomplished using the following configuration on the host:
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```nix
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networking.nat.enable = true;
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networking.nat.internalInterfaces = ["ve-+"];
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networking.nat.externalInterface = "eth0";
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```
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where `eth0` should be replaced with the desired external interface.
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Note that `ve-+` is a wildcard that matches all container interfaces.
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If you are using Network Manager, you need to explicitly prevent it from
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managing container interfaces:
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```nix
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networking.networkmanager.unmanaged = [ "interface-name:ve-*" ];
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```
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You may need to restart your system for the changes to take effect.
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@ -1,59 +0,0 @@
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<section xmlns="http://docbook.org/ns/docbook"
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xmlns:xlink="http://www.w3.org/1999/xlink"
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xmlns:xi="http://www.w3.org/2001/XInclude"
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version="5.0"
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xml:id="sec-container-networking">
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<title>Container Networking</title>
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<para>
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When you create a container using <literal>nixos-container create</literal>,
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it gets it own private IPv4 address in the range
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<literal>10.233.0.0/16</literal>. You can get the container’s IPv4 address
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as follows:
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<screen>
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<prompt># </prompt>nixos-container show-ip foo
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10.233.4.2
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<prompt>$ </prompt>ping -c1 10.233.4.2
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64 bytes from 10.233.4.2: icmp_seq=1 ttl=64 time=0.106 ms
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</screen>
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</para>
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<para>
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Networking is implemented using a pair of virtual Ethernet devices. The
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network interface in the container is called <literal>eth0</literal>, while
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the matching interface in the host is called
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<literal>ve-<replaceable>container-name</replaceable></literal> (e.g.,
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<literal>ve-foo</literal>). The container has its own network namespace and
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the <literal>CAP_NET_ADMIN</literal> capability, so it can perform arbitrary
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network configuration such as setting up firewall rules, without affecting or
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having access to the host’s network.
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</para>
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<para>
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By default, containers cannot talk to the outside network. If you want that,
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you should set up Network Address Translation (NAT) rules on the host to
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rewrite container traffic to use your external IP address. This can be
|
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accomplished using the following configuration on the host:
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<programlisting>
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<xref linkend="opt-networking.nat.enable"/> = true;
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<xref linkend="opt-networking.nat.internalInterfaces"/> = ["ve-+"];
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<xref linkend="opt-networking.nat.externalInterface"/> = "eth0";
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</programlisting>
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where <literal>eth0</literal> should be replaced with the desired external
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interface. Note that <literal>ve-+</literal> is a wildcard that matches all
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container interfaces.
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</para>
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<para>
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If you are using Network Manager, you need to explicitly prevent it from
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managing container interfaces:
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<programlisting>
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networking.networkmanager.unmanaged = [ "interface-name:ve-*" ];
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</programlisting>
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</para>
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<para>
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You may need to restart your system for the changes to take effect.
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</para>
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</section>
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@ -28,7 +28,7 @@
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contrast, in the imperative approach, containers are configured and updated
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independently from the host system.
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</para>
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<xi:include href="imperative-containers.xml" />
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<xi:include href="declarative-containers.xml" />
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<xi:include href="container-networking.xml" />
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<xi:include href="../from_md/administration/imperative-containers.section.xml" />
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<xi:include href="../from_md/administration/declarative-containers.section.xml" />
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<xi:include href="../from_md/administration/container-networking.section.xml" />
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</chapter>
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@ -0,0 +1,48 @@
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# Declarative Container Specification {#sec-declarative-containers}
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You can also specify containers and their configuration in the host's
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`configuration.nix`. For example, the following specifies that there
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shall be a container named `database` running PostgreSQL:
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```nix
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containers.database =
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{ config =
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{ config, pkgs, ... }:
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{ services.postgresql.enable = true;
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services.postgresql.package = pkgs.postgresql_9_6;
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};
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};
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```
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If you run `nixos-rebuild switch`, the container will be built. If the
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container was already running, it will be updated in place, without
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rebooting. The container can be configured to start automatically by
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setting `containers.database.autoStart = true` in its configuration.
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By default, declarative containers share the network namespace of the
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host, meaning that they can listen on (privileged) ports. However, they
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cannot change the network configuration. You can give a container its
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own network as follows:
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```nix
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containers.database = {
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privateNetwork = true;
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hostAddress = "192.168.100.10";
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localAddress = "192.168.100.11";
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};
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```
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This gives the container a private virtual Ethernet interface with IP
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address `192.168.100.11`, which is hooked up to a virtual Ethernet
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interface on the host with IP address `192.168.100.10`. (See the next
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section for details on container networking.)
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To disable the container, just remove it from `configuration.nix` and
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run `nixos-rebuild
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switch`. Note that this will not delete the root directory of the
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container in `/var/lib/containers`. Containers can be destroyed using
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the imperative method: `nixos-container destroy foo`.
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Declarative containers can be started and stopped using the
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corresponding systemd service, e.g.
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`systemctl start container@database`.
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@ -1,60 +0,0 @@
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<section xmlns="http://docbook.org/ns/docbook"
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xmlns:xlink="http://www.w3.org/1999/xlink"
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xmlns:xi="http://www.w3.org/2001/XInclude"
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version="5.0"
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xml:id="sec-declarative-containers">
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<title>Declarative Container Specification</title>
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<para>
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You can also specify containers and their configuration in the host’s
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<filename>configuration.nix</filename>. For example, the following specifies
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that there shall be a container named <literal>database</literal> running
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PostgreSQL:
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<programlisting>
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containers.database =
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{ config =
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{ config, pkgs, ... }:
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{ <xref linkend="opt-services.postgresql.enable"/> = true;
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<xref linkend="opt-services.postgresql.package"/> = pkgs.postgresql_9_6;
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};
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};
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</programlisting>
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If you run <literal>nixos-rebuild switch</literal>, the container will be
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built. If the container was already running, it will be updated in place,
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without rebooting. The container can be configured to start automatically by
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setting <literal>containers.database.autoStart = true</literal> in its
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configuration.
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</para>
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<para>
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By default, declarative containers share the network namespace of the host,
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meaning that they can listen on (privileged) ports. However, they cannot
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change the network configuration. You can give a container its own network as
|
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follows:
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<programlisting>
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containers.database = {
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<link linkend="opt-containers._name_.privateNetwork">privateNetwork</link> = true;
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<link linkend="opt-containers._name_.hostAddress">hostAddress</link> = "192.168.100.10";
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<link linkend="opt-containers._name_.localAddress">localAddress</link> = "192.168.100.11";
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};
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</programlisting>
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This gives the container a private virtual Ethernet interface with IP address
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<literal>192.168.100.11</literal>, which is hooked up to a virtual Ethernet
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interface on the host with IP address <literal>192.168.100.10</literal>. (See
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the next section for details on container networking.)
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</para>
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<para>
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To disable the container, just remove it from
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<filename>configuration.nix</filename> and run <literal>nixos-rebuild
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switch</literal>. Note that this will not delete the root directory of the
|
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container in <literal>/var/lib/containers</literal>. Containers can be
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destroyed using the imperative method: <literal>nixos-container destroy
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foo</literal>.
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</para>
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<para>
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Declarative containers can be started and stopped using the corresponding
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systemd service, e.g. <literal>systemctl start container@database</literal>.
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</para>
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</section>
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115
nixos/doc/manual/administration/imperative-containers.section.md
Normal file
115
nixos/doc/manual/administration/imperative-containers.section.md
Normal file
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@ -0,0 +1,115 @@
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# Imperative Container Management {#sec-imperative-containers}
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We'll cover imperative container management using `nixos-container`
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first. Be aware that container management is currently only possible as
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`root`.
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You create a container with identifier `foo` as follows:
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```ShellSession
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# nixos-container create foo
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```
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This creates the container's root directory in `/var/lib/containers/foo`
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and a small configuration file in `/etc/containers/foo.conf`. It also
|
||||
builds the container's initial system configuration and stores it in
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||||
`/nix/var/nix/profiles/per-container/foo/system`. You can modify the
|
||||
initial configuration of the container on the command line. For
|
||||
instance, to create a container that has `sshd` running, with the given
|
||||
public key for `root`:
|
||||
|
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```ShellSession
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# nixos-container create foo --config '
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services.openssh.enable = true;
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||||
users.users.root.openssh.authorizedKeys.keys = ["ssh-dss AAAAB3N…"];
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||||
'
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```
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By default the next free address in the `10.233.0.0/16` subnet will be
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chosen as container IP. This behavior can be altered by setting
|
||||
`--host-address` and `--local-address`:
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||||
|
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```ShellSession
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# nixos-container create test --config-file test-container.nix \
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--local-address 10.235.1.2 --host-address 10.235.1.1
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```
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Creating a container does not start it. To start the container, run:
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```ShellSession
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# nixos-container start foo
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||||
```
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||||
|
||||
This command will return as soon as the container has booted and has
|
||||
reached `multi-user.target`. On the host, the container runs within a
|
||||
systemd unit called `container@container-name.service`. Thus, if
|
||||
something went wrong, you can get status info using `systemctl`:
|
||||
|
||||
```ShellSession
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# systemctl status container@foo
|
||||
```
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|
||||
If the container has started successfully, you can log in as root using
|
||||
the `root-login` operation:
|
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|
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```ShellSession
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||||
# nixos-container root-login foo
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||||
[root@foo:~]#
|
||||
```
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|
||||
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
|
||||
`login` operation, which is available to all users on the host:
|
||||
|
||||
```ShellSession
|
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# nixos-container login foo
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||||
foo login: alice
|
||||
Password: ***
|
||||
```
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|
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With `nixos-container run`, you can execute arbitrary commands in the
|
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container:
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|
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```ShellSession
|
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# nixos-container run foo -- uname -a
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||||
Linux foo 3.4.82 #1-NixOS SMP Thu Mar 20 14:44:05 UTC 2014 x86_64 GNU/Linux
|
||||
```
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|
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There are several ways to change the configuration of the container.
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First, on the host, you can edit
|
||||
`/var/lib/container/name/etc/nixos/configuration.nix`, and run
|
||||
|
||||
```ShellSession
|
||||
# nixos-container update foo
|
||||
```
|
||||
|
||||
This will build and activate the new configuration. You can also specify
|
||||
a new configuration on the command line:
|
||||
|
||||
```ShellSession
|
||||
# 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">…
|
||||
```
|
||||
|
||||
However, note that this will overwrite the container's
|
||||
`/etc/nixos/configuration.nix`.
|
||||
|
||||
Alternatively, you can change the configuration from within the
|
||||
container itself by running `nixos-rebuild switch` inside the container.
|
||||
Note that the container by default does not have a copy of the NixOS
|
||||
channel, so you should run `nix-channel --update` first.
|
||||
|
||||
Containers can be stopped and started using `nixos-container
|
||||
stop` and `nixos-container start`, respectively, or by using
|
||||
`systemctl` on the container's service unit. To destroy a container,
|
||||
including its file system, do
|
||||
|
||||
```ShellSession
|
||||
# nixos-container destroy foo
|
||||
```
|
||||
|
|
@ -1,123 +0,0 @@
|
|||
<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>
|
||||
<prompt># </prompt>nixos-container create <replaceable>foo</replaceable>
|
||||
</screen>
|
||||
This creates the container’s root directory in
|
||||
<filename>/var/lib/containers/<replaceable>foo</replaceable></filename> and a small configuration file
|
||||
in <filename>/etc/containers/<replaceable>foo</replaceable>.conf</filename>. It also builds the
|
||||
container’s initial system configuration and stores it in
|
||||
<filename>/nix/var/nix/profiles/per-container/<replaceable>foo</replaceable>/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>
|
||||
<prompt># </prompt>nixos-container create <replaceable>foo</replaceable> --config '
|
||||
<xref linkend="opt-services.openssh.enable"/> = true;
|
||||
<link linkend="opt-users.users._name_.openssh.authorizedKeys.keys">users.users.root.openssh.authorizedKeys.keys</link> = ["ssh-dss AAAAB3N…"];
|
||||
'
|
||||
</screen>
|
||||
By default the next free address in the <literal>10.233.0.0/16</literal> subnet will be chosen
|
||||
as container IP. This behavior can be altered by setting <literal>--host-address</literal> and
|
||||
<literal>--local-address</literal>:
|
||||
<screen>
|
||||
<prompt># </prompt>nixos-container create test --config-file test-container.nix \
|
||||
--local-address 10.235.1.2 --host-address 10.235.1.1
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Creating a container does not start it. To start the container, run:
|
||||
<screen>
|
||||
<prompt># </prompt>nixos-container start <replaceable>foo</replaceable>
|
||||
</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>
|
||||
<prompt># </prompt>systemctl status container@<replaceable>foo</replaceable>
|
||||
</screen>
|
||||
</para>
|
||||
|
||||
<para>
|
||||
If the container has started successfully, you can log in as root using the
|
||||
<command>root-login</command> operation:
|
||||
<screen>
|
||||
<prompt># </prompt>nixos-container root-login <replaceable>foo</replaceable>
|
||||
<prompt>[root@foo:~]#</prompt>
|
||||
</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>
|
||||
<prompt># </prompt>nixos-container login <replaceable>foo</replaceable>
|
||||
foo login: alice
|
||||
Password: ***
|
||||
</screen>
|
||||
With <command>nixos-container run</command>, you can execute arbitrary
|
||||
commands in the container:
|
||||
<screen>
|
||||
<prompt># </prompt>nixos-container run <replaceable>foo</replaceable> -- 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>
|
||||
<prompt># </prompt>nixos-container update <replaceable>foo</replaceable>
|
||||
</screen>
|
||||
This will build and activate the new configuration. You can also specify a
|
||||
new configuration on the command line:
|
||||
<screen>
|
||||
<prompt># </prompt>nixos-container update <replaceable>foo</replaceable> --config '
|
||||
<xref linkend="opt-services.httpd.enable"/> = true;
|
||||
<xref linkend="opt-services.httpd.adminAddr"/> = "foo@example.org";
|
||||
<xref linkend="opt-networking.firewall.allowedTCPPorts"/> = [ 80 ];
|
||||
'
|
||||
|
||||
<prompt># </prompt>curl http://$(nixos-container show-ip <replaceable>foo</replaceable>)/
|
||||
<!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>
|
||||
<prompt># </prompt>nixos-container destroy <replaceable>foo</replaceable>
|
||||
</screen>
|
||||
</para>
|
||||
</section>
|
||||
|
|
@ -0,0 +1,54 @@
|
|||
<section xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xml:id="sec-container-networking">
|
||||
<title>Container Networking</title>
|
||||
<para>
|
||||
When you create a container using
|
||||
<literal>nixos-container create</literal>, it gets it own private
|
||||
IPv4 address in the range <literal>10.233.0.0/16</literal>. You can
|
||||
get the container’s IPv4 address as follows:
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container show-ip foo
|
||||
10.233.4.2
|
||||
|
||||
$ ping -c1 10.233.4.2
|
||||
64 bytes from 10.233.4.2: icmp_seq=1 ttl=64 time=0.106 ms
|
||||
</programlisting>
|
||||
<para>
|
||||
Networking is implemented using a pair of virtual Ethernet devices.
|
||||
The network interface in the container is called
|
||||
<literal>eth0</literal>, while the matching interface in the host is
|
||||
called <literal>ve-container-name</literal> (e.g.,
|
||||
<literal>ve-foo</literal>). The container has its own network
|
||||
namespace and the <literal>CAP_NET_ADMIN</literal> capability, so it
|
||||
can perform arbitrary network configuration such as setting up
|
||||
firewall rules, without affecting or having access to the host’s
|
||||
network.
|
||||
</para>
|
||||
<para>
|
||||
By default, containers cannot talk to the outside network. If you
|
||||
want that, you should set up Network Address Translation (NAT) rules
|
||||
on the host to rewrite container traffic to use your external IP
|
||||
address. This can be accomplished using the following configuration
|
||||
on the host:
|
||||
</para>
|
||||
<programlisting language="bash">
|
||||
networking.nat.enable = true;
|
||||
networking.nat.internalInterfaces = ["ve-+"];
|
||||
networking.nat.externalInterface = "eth0";
|
||||
</programlisting>
|
||||
<para>
|
||||
where <literal>eth0</literal> should be replaced with the desired
|
||||
external interface. Note that <literal>ve-+</literal> is a wildcard
|
||||
that matches all container interfaces.
|
||||
</para>
|
||||
<para>
|
||||
If you are using Network Manager, you need to explicitly prevent it
|
||||
from managing container interfaces:
|
||||
</para>
|
||||
<programlisting language="bash">
|
||||
networking.networkmanager.unmanaged = [ "interface-name:ve-*" ];
|
||||
</programlisting>
|
||||
<para>
|
||||
You may need to restart your system for the changes to take effect.
|
||||
</para>
|
||||
</section>
|
||||
|
|
@ -0,0 +1,60 @@
|
|||
<section xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xml:id="sec-declarative-containers">
|
||||
<title>Declarative Container Specification</title>
|
||||
<para>
|
||||
You can also specify containers and their configuration in the
|
||||
host’s <literal>configuration.nix</literal>. For example, the
|
||||
following specifies that there shall be a container named
|
||||
<literal>database</literal> running PostgreSQL:
|
||||
</para>
|
||||
<programlisting language="bash">
|
||||
containers.database =
|
||||
{ config =
|
||||
{ config, pkgs, ... }:
|
||||
{ services.postgresql.enable = true;
|
||||
services.postgresql.package = pkgs.postgresql_9_6;
|
||||
};
|
||||
};
|
||||
</programlisting>
|
||||
<para>
|
||||
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:
|
||||
</para>
|
||||
<programlisting language="bash">
|
||||
containers.database = {
|
||||
privateNetwork = true;
|
||||
hostAddress = "192.168.100.10";
|
||||
localAddress = "192.168.100.11";
|
||||
};
|
||||
</programlisting>
|
||||
<para>
|
||||
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
|
||||
<literal>configuration.nix</literal> 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>
|
||||
|
|
@ -0,0 +1,131 @@
|
|||
<section xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xml:id="sec-imperative-containers">
|
||||
<title>Imperative Container Management</title>
|
||||
<para>
|
||||
We’ll cover imperative container management using
|
||||
<literal>nixos-container</literal> 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:
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container create foo
|
||||
</programlisting>
|
||||
<para>
|
||||
This creates the container’s root directory in
|
||||
<literal>/var/lib/containers/foo</literal> and a small configuration
|
||||
file in <literal>/etc/containers/foo.conf</literal>. It also builds
|
||||
the container’s initial system configuration and stores it in
|
||||
<literal>/nix/var/nix/profiles/per-container/foo/system</literal>.
|
||||
You can modify the initial configuration of the container on the
|
||||
command line. For instance, to create a container that has
|
||||
<literal>sshd</literal> running, with the given public key for
|
||||
<literal>root</literal>:
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container create foo --config '
|
||||
services.openssh.enable = true;
|
||||
users.users.root.openssh.authorizedKeys.keys = ["ssh-dss AAAAB3N…"];
|
||||
'
|
||||
</programlisting>
|
||||
<para>
|
||||
By default the next free address in the
|
||||
<literal>10.233.0.0/16</literal> subnet will be chosen as container
|
||||
IP. This behavior can be altered by setting
|
||||
<literal>--host-address</literal> and
|
||||
<literal>--local-address</literal>:
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container create test --config-file test-container.nix \
|
||||
--local-address 10.235.1.2 --host-address 10.235.1.1
|
||||
</programlisting>
|
||||
<para>
|
||||
Creating a container does not start it. To start the container, run:
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container start foo
|
||||
</programlisting>
|
||||
<para>
|
||||
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@container-name.service</literal>. Thus, if
|
||||
something went wrong, you can get status info using
|
||||
<literal>systemctl</literal>:
|
||||
</para>
|
||||
<programlisting>
|
||||
# systemctl status container@foo
|
||||
</programlisting>
|
||||
<para>
|
||||
If the container has started successfully, you can log in as root
|
||||
using the <literal>root-login</literal> operation:
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container root-login foo
|
||||
[root@foo:~]#
|
||||
</programlisting>
|
||||
<para>
|
||||
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
|
||||
<literal>login</literal> operation, which is available to all users
|
||||
on the host:
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container login foo
|
||||
foo login: alice
|
||||
Password: ***
|
||||
</programlisting>
|
||||
<para>
|
||||
With <literal>nixos-container run</literal>, you can execute
|
||||
arbitrary commands in the container:
|
||||
</para>
|
||||
<programlisting>
|
||||
# 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
|
||||
</programlisting>
|
||||
<para>
|
||||
There are several ways to change the configuration of the container.
|
||||
First, on the host, you can edit
|
||||
<literal>/var/lib/container/name/etc/nixos/configuration.nix</literal>,
|
||||
and run
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container update foo
|
||||
</programlisting>
|
||||
<para>
|
||||
This will build and activate the new configuration. You can also
|
||||
specify a new configuration on the command line:
|
||||
</para>
|
||||
<programlisting>
|
||||
# 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">…
|
||||
</programlisting>
|
||||
<para>
|
||||
However, note that this will overwrite the container’s
|
||||
<literal>/etc/nixos/configuration.nix</literal>.
|
||||
</para>
|
||||
<para>
|
||||
Alternatively, you can change the configuration from within the
|
||||
container itself by running <literal>nixos-rebuild switch</literal>
|
||||
inside the container. Note that the container by default does not
|
||||
have a copy of the NixOS channel, so you should run
|
||||
<literal>nix-channel --update</literal> 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
|
||||
<literal>systemctl</literal> on the container’s service unit. To
|
||||
destroy a container, including its file system, do
|
||||
</para>
|
||||
<programlisting>
|
||||
# nixos-container destroy foo
|
||||
</programlisting>
|
||||
</section>
|
||||
Loading…
Reference in a new issue