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+# Imperative Container Management {#sec-imperative-containers}
+
+We'll cover imperative container management using `nixos-container`
+first. Be aware that container management is currently only possible as
+`root`.
+
+You create a container with identifier `foo` as follows:
+
+```ShellSession
+# nixos-container create foo
+```
+
+This creates the container's root directory in `/var/lib/containers/foo`
+and a small configuration file in `/etc/containers/foo.conf`. It also
+builds the container's initial system configuration and stores it in
+`/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`:
+
+```ShellSession
+# nixos-container create foo --config '
+  services.openssh.enable = true;
+  users.users.root.openssh.authorizedKeys.keys = ["ssh-dss AAAAB3N…"];
+'
+```
+
+By default the next free address in the `10.233.0.0/16` subnet will be
+chosen as container IP. This behavior can be altered by setting
+`--host-address` and `--local-address`:
+
+```ShellSession
+# nixos-container create test --config-file test-container.nix \
+    --local-address 10.235.1.2 --host-address 10.235.1.1
+```
+
+Creating a container does not start it. To start the container, run:
+
+```ShellSession
+# nixos-container start foo
+```
+
+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
+# systemctl status container@foo
+```
+
+If the container has started successfully, you can log in as root using
+the `root-login` operation:
+
+```ShellSession
+# nixos-container root-login foo
+[root@foo:~]#
+```
+
+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
+# nixos-container login foo
+foo login: alice
+Password: ***
+```
+
+With `nixos-container run`, you can execute arbitrary commands in the
+container:
+
+```ShellSession
+# 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
+```
+
+There are several ways to change the configuration of the container.
+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
+```