FreeBSD Handbook
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# 4.2 Virtual Consoles and Terminals

FreeBSD can be used in various ways. One of them is typing commands to a text terminal. A lot of the flexibility and power of a UNIX® operating system is readily available at your hands when using FreeBSD this way. This section describes what terminals and consoles are, and how you can use them in FreeBSD.

## 4.2.1 The Console

If you have not configured FreeBSD to automatically start a graphical environment during startup, the system will present you with a login prompt after it boots, right after the startup scripts finish running. You will see something similar to:

    Additional ABI support:.
    Local package initialization:.
    Additional TCP options:.

    Fri Sep 20 13:01:06 EEST 2002

    FreeBSD/i386 (pc3.example.org) (ttyv0)

    login:

The messages might be a bit different on your system, but you will see something similar. The last two lines are what we are interested in right now. The second last line reads:

    FreeBSD/i386 (pc3.example.org) (ttyv0)

This line contains some bits of information about the system you have just booted. You are looking at a FreeBSD console, running on an Intel or compatible processor of the x86 architecture[1]. The name of this machine (every UNIX machine has a name) is `pc3.example.org`, and you are now looking at its system console--the `ttyv0` terminal.

Finally, the last line is always:

    login:

This is the part where you are supposed to type in your username to log into FreeBSD. The next section describes how you can do this.

## 4.2.2 Logging into FreeBSD

FreeBSD is a multiuser, multiprocessing system. This is the formal description that is usually given to a system that can be used by many different people, who simultaneously run a lot of programs on a single machine.

Every multiuser system needs some way to distinguish one user from the rest. In FreeBSD (and all the UNIX-like operating systems), this is accomplished by requiring that every user must log into the system before being able to run programs. Every user has a unique name (the username) and a personal, secret key (the password). FreeBSD will ask for these two before allowing a user to run any programs.

Right after FreeBSD boots and finishes running its startup scripts[2], it will present you with a prompt and ask for a valid username:

    login:

For the sake of this example, let us assume that your username is `john`. Type `john` at this prompt and press Enter. You should then be presented with a prompt to enter a password:

    login: john
    Password:

Type in `john`'s password now, and press Enter. The password is not echoed! You need not worry about this right now. Suffice it to say that it is done for security reasons.

If you have typed your password correctly, you should by now be logged into FreeBSD and ready to try out all the available commands.

You should see the MOTD or message of the day followed by a command prompt (a `#`, `$`, or `%` character). This indicates you have successfully logged into FreeBSD.

## 4.2.3 Multiple Consoles

Running UNIX commands in one console is fine, but FreeBSD can run many programs at once. Having one console where commands can be typed would be a bit of a waste when an operating system like FreeBSD can run dozens of programs at the same time. This is where virtual consoles can be very helpful.

FreeBSD can be configured to present you with many different virtual consoles. You can switch from one of them to any other virtual console by pressing a couple of keys on your keyboard. Each console has its own different output channel, and FreeBSD takes care of properly redirecting keyboard input and monitor output as you switch from one virtual console to the next.

Special key combinations have been reserved by FreeBSD for switching consoles[3]. You can use Alt-F1, Alt-F2, through Alt-F8 to switch to a different virtual console in FreeBSD.

As you are switching from one console to the next, FreeBSD takes care of saving and restoring the screen output. The result is an illusion of having multiple virtual screens and keyboards that you can use to type commands for FreeBSD to run. The programs that you launch on one virtual console do not stop running when that console is not visible. They continue running when you have switched to a different virtual console.

## 4.2.4 The `/etc/ttys` File

The default configuration of FreeBSD will start up with eight virtual consoles. This is not a hardwired setting though, and you can easily customize your installation to boot with more or fewer virtual consoles. The number and settings of the virtual consoles are configured in the `/etc/ttys` file.

You can use the `/etc/ttys` file to configure the virtual consoles of FreeBSD. Each uncommented line in this file (lines that do not start with a `#` character) contains settings for a single terminal or virtual console. The default version of this file that ships with FreeBSD configures nine virtual consoles, and enables eight of them. They are the lines that start with `ttyv`:

    # name  getty                           type    status          comments
    #
    ttyv0   "/usr/libexec/getty Pc"         cons25  on  secure
    # Virtual terminals
    ttyv1   "/usr/libexec/getty Pc"         cons25  on  secure
    ttyv2   "/usr/libexec/getty Pc"         cons25  on  secure
    ttyv3   "/usr/libexec/getty Pc"         cons25  on  secure
    ttyv4   "/usr/libexec/getty Pc"         cons25  on  secure
    ttyv5   "/usr/libexec/getty Pc"         cons25  on  secure
    ttyv6   "/usr/libexec/getty Pc"         cons25  on  secure
    ttyv7   "/usr/libexec/getty Pc"         cons25  on  secure
    ttyv8   "/usr/X11R6/bin/xdm -nodaemon"  xterm   off secure

For a detailed description of every column in this file and all the options you can use to set things up for the virtual consoles, consult the ttys(5) manual page.

## 4.2.5 Single User Mode Console

A detailed description of what single user mode is can be found in Section 13.6.2. It is worth noting that there is only one console when you are running FreeBSD in single user mode. There are no virtual consoles available. The settings of the single user mode console can also be found in the `/etc/ttys` file. Look for the line that starts with `console`:

    # name  getty                           type    status          comments
    #
    # If console is marked "insecure", then init will ask for the root password
    # when going to single-user mode.
    console none                            unknown off secure

> Note: As the comments above the `console` line indicate, you can edit this line and change `secure` to `insecure`. If you do that, when FreeBSD boots into single user mode, it will still ask for the `root` password.

> Be careful when changing this to `insecure`. If you ever forget the `root` password, booting into single user mode is a bit involved. It is still possible, but it might be a bit hard for someone who is not very comfortable with the FreeBSD booting process and the programs involved.

## 4.2.6 Changing Console Video Modes

The FreeBSD console default video mode may be adjusted to 1024x768, 1280x1024, or any other size supported by your graphics chip and monitor. To use a different video mode, you first must recompile your kernel and include two additional options:

    options VESA
    options SC_PIXEL_MODE

Once the kernel has been recompiled with these two options, you can then determine what video modes are supported by your hardware by using the vidcontrol(1) utility. To get a list of supported video modes issue the following:

    # vidcontrol -i mode

The output of this command is a list of video modes that are supported by your hardware. You can then choose to use a new video mode by passing it to vidcontrol(1) in a `root` console:

    # vidcontrol MODE_279

If the new video mode is acceptable, it can be permanently set on boot by setting it in the `/etc/rc.conf` file:

    allscreens_flags="MODE_279"

### Notes

[1] | This is what `i386` means. Note that even if you are not running FreeBSD on an Intel 386 CPU, this is going to be `i386`. It is not the type of your processor, but the processor architecture that is shown here.
[2] | Startup scripts are programs that are run automatically by FreeBSD when booting. Their main function is to set things up for everything else to run, and start any services that you have configured to run in the background doing useful things.
[3] | A fairly technical and accurate description of all the details of the FreeBSD console and keyboard drivers can be found in the manual pages of syscons(4), atkbd(4), vidcontrol(1) and kbdcontrol(1). We will not expand on the details here, but the interested reader can always consult the manual pages for a more detailed and thorough explanation of how things work.

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