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# 7 Using a Serial Console on FreeBSD

The procedure for doing this is described in detail in the FreeBSD Handbook. This is a quick summary.

## 7.1 Check the kernel configuration

Check that the kernel configuration file has `flags 0x10` in the config line for the `sio0` device. This signals this device (known as `COM1` in DOS/Windows® or `/dev/ttyd0` in FreeBSD) can be used as a console. This flag is set on the `GENERIC` and `LINT` sample configs, so is likely to be set in your kernel.

## 7.2 Create the `/boot.conf` file

This file should be created containing a single line containing just `-h` (minus the quotes). This tells the FreeBSD boot blocks to use the serial console.

## 7.3 Edit `/etc/ttys`

Edit this file and make the following changes.

If you are not going to have any keyboard/video screen on this server at all, you should find all the lines for `ttyv` devices like

    ttyv1   "/usr/libexec/getty Pc"         cons25  on  secure

Change the `on` to `off`. This will stop login screens being run on the useless video consoles.

Find the line containing `ttyd0`. Change it from

    ttyd0   "/usr/libexec/getty std.9600"   dialup  off secure

to

    ttyd0   "/usr/libexec/getty std.9600"   vt100   on secure

(replacing `vt100` with the term type of your console. The `xterms` terminal type might be a good choice). This allows you to log in to the console port once the system is running multi-user.

Reboot and off you go!

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