mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-11-15 22:36:23 +01:00
115 lines
3.5 KiB
Markdown
115 lines
3.5 KiB
Markdown
# 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/nixos-containers/foo`
|
|
and a small configuration file in `/etc/nixos-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/nixos-containers/foo/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
|
|
```
|