# Configuration

## Automatic

You can use an USB drive with HassOS to configure network options, SSH access to the host and to install updates.
Format a USB stick with FAT32/EXT4/NTFS and name it `CONFIG`. Alternative you can create a `CONFIG` folder inside boot partition. Use the following directory structure within the USB drive:

```text
network/
modules/
modprobe/
udev/
authorized_keys
timesyncd.conf
hassos-xy.raucb
```

- The `network` folder can contain any kind of NetworkManager connection files. For more information see [Network][network.md].
- The `modules` folder is for modules-load configuration files.
- The `modprobe` folder is for modules configuration files (/etc/modprobe.d)
- The `udev` folder is for udev rules files.
- The `authorized_keys` file activates debug SSH access on port `22222`. See [Debugging Hassio][debug-hassio].
- The `timesyncd.conf` file allow you to set different NTP servers. HassOS won't boot without correct working time servers!
- The `hassos-*.raucb` file is a firmware OTA update which will be installed. These can be found on on the [release][hassos-release] page.

You can put this USB stick into the device and it will be read on startup. You can also trigger this process later over the
API/UI or by calling `systemctl restart hassos-config` on the host.

## Local

### Bootargs

You can edit or create a `cmdline.txt` in your boot partition. That will be read from the bootloader.

### Kernel-Module

The kernel module folder `/etc/modules-load.d` is persistent and you can add your configuration files there. See [Systemd modules load][systemd-modules]. You can add the modules configuration files in `/etc/modprobe.d` that is also persistent.

### Udev rules

The udev rules folder `/etc/udev/rules.d` is persistent and you can add your configuration files there.

### Network

You can manual add, edit or remove connections configurations from `/etc/NetworkManager/system-connections`.

### NTP

You can manual edit the systemd timesync file on `/etc/systemd/timesyncd.conf`.
Our default ntp configuration look like:
```
[Time]
NTP=time1.google.com time2.google.com time3.google.com
FallbackNTP=0.pool.ntp.org 1.pool.ntp.org 2.pool.ntp.org 3.pool.ntp.org
```

[systemd-modules]: https://www.freedesktop.org/software/systemd/man/modules-load.d.html
[network.md]: network.md
[hassos-release]: https://github.com/home-assistant/hassos/releases/
[debug-hassio]: https://developers.home-assistant.io/docs/en/hassio_debugging.html