# Using the &debian; Installer

## How the Installer Works

For this architecture the &d-i; supports two different user interfaces: a graphical one and a text-based one. The graphical interface is used by default unless you select an Install option in the boot menu. For more information about booting the graphical installer, please refer to graphical.

For this architecture the &d-i; supports two different user interfaces: a text-based one and a graphical one. The text-based interface is used by default unless you select an Graphical install option in the boot menu. For more information about booting the graphical installer, please refer to graphical.

For this architecture the installer uses a text-based user interface. A graphical user interface is currently not available.

The &debian; Installer consists of a number of special-purpose components to perform each installation task. Each component performs its task, asking the user questions as necessary to do its job. The questions themselves are given priorities, and the priority of questions to be asked is set when the installer is started.

When a default installation is performed, only essential (high priority) questions will be asked. This results in a highly automated installation process with little user interaction. Components are automatically run in sequence; which components are run depends mainly on the installation method you use and on your hardware. The installer will use default values for questions that are not asked.

If there is a problem, the user will see an error screen, and the installer menu may be shown in order to select some alternative action. If there are no problems, the user will never see the installer menu, but will simply answer questions for each component in turn. Serious error notifications are set to priority critical so the user will always be notified.

Some of the defaults that the installer uses can be influenced by passing boot arguments when &d-i; is started. If, for example, you wish to force static network configuration (IPv6 autoconfiguration and DHCP are used by default if available), you could add the boot parameter `netcfg/disable_autoconfig=true`. See installer-args for available options.

Power users may be more comfortable with a menu-driven interface, where each step is controlled by the user rather than the installer performing each step automatically in sequence. To use the installer in a manual, menu-driven way, add the boot argument `priority=medium`.

If your hardware requires you to pass options to kernel modules as they are installed, you will need to start the installer in expert mode. This can be done by either using the `expert` command to start the installer or by adding the boot argument `priority=low`. Expert mode gives you full control over &d-i;.

In the text-based environment the use of a mouse is not supported. Here are the keys you can use to navigate within the various dialogs. The Tab or right arrow keys move forward, and the Shift Tab or left arrow keys move backward between displayed buttons and selections. The up and down arrow select different items within a scrollable list, and also scroll the list itself. In addition, in long lists, you can type a letter to cause the list to scroll directly to the section with items starting with the letter you typed and use Pg-Up and Pg-Down to scroll the list in sections. The space bar selects an item such as a checkbox. Use &enterkey; to activate choices.

Some dialogs may offer additional help information. If help is available this will be indicated on the bottom line of the screen by displaying that help information can be accessed by pressing the F1 key.

S/390 does not support virtual consoles. You may open a second and third ssh session to view the logs described below.

Error messages and logs are redirected to the fourth console. You can access this console by pressing Left Alt F4 (hold the left Alt key while pressing the F4 function key); get back to the main installer process with Left Alt F1.

These messages can also be found in `/var/log/syslog`. After installation, this log is copied to `/var/log/installer/syslog` on your new system. Other installation messages may be found in `/var/log/` during the installation, and `/var/log/installer/` after the computer has been booted into the installed system.

### Using the graphical installer

The graphical installer basically works the same as the text-based installer and thus the rest of this manual can be used to guide you through the installation process.

If you prefer using the keyboard over the mouse, there are two things you need to know. To expand a collapsed list (used for example for the selection of countries within continents), you can use the + and - keys. For questions where more than one item can be selected (e.g. task selection), you first need to tab to the &BTN-CONT; button after making your selections; hitting enter will toggle a selection, not activate &BTN-CONT;.

If a dialog offers additional help information, a Help button will be displayed. The help information can be accessed either by activating the button or by pressing the F1 key.

To switch to another console, you will also need to use the Ctrl key, just as with the X Window System. For example, to switch to VT2 (the first debug shell) you would use: Ctrl Left Alt F2 . The graphical installer itself runs on VT5, so you can use Left Alt F5 to switch back.

## Components Introduction

Here is a list of installer components with a brief description of each component's purpose. Details you might need to know about using a particular component are in module-details.

main-menu

- Shows the list of components to the user during installer operation, and starts a component when it is selected. Main-menu's questions are set to priority medium, so if your priority is set to high or critical (high is the default), you will not see the menu. On the other hand, if there is an error which requires your intervention, the question priority may be downgraded temporarily to allow you to resolve the problem, and in that case the menu may appear.

  You can get to the main menu by selecting the &BTN-GOBACK; button repeatedly to back all the way out of the currently running component.

localechooser

- Allows the user to select localization options for the installation and the installed system: language, country and locales. The installer will display messages in the selected language, unless the translation for that language is not complete in which case some messages may be shown in English.

console-setup

- Shows a list of keyboard (layouts), from which the user chooses the one which matches his own model.

hw-detect

- Automatically detects most of the system's hardware, including network cards, disk drives, and PCMCIA.

cdrom-detect

- Looks for and mounts a &debian; installation media.

netcfg

- Configures the computer's network connections so it can communicate over the internet.

iso-scan

- Searches for ISO images (`.iso` files) on hard drives.

choose-mirror

- Presents a list of &debian; archive mirrors. The user may choose the source of his installation packages.

cdrom-checker

- Checks integrity of installation media. This way, the user may assure him/herself that the installation image was not corrupted.

lowmem

- Lowmem tries to detect systems with low memory and then does various tricks to remove unnecessary parts of &d-i; from the memory (at the cost of some features).

anna

- Anna's Not Nearly APT. Installs packages which have been retrieved from the chosen mirror or installation media.

user-setup

- Sets up the root password, and adds a non-root user.

clock-setup

- Updates the system clock and determines whether the clock is set to UTC or not.

tzsetup

- Selects the time zone, based on the location selected earlier.

partman

- Allows the user to partition disks attached to the system, create file systems on the selected partitions, and attach them to the mountpoints. Included are also interesting features like a fully automatic mode or LVM support. This is the preferred partitioning tool in &debian;.

partman-lvm

- Helps the user with the configuration of the LVM (Logical Volume Manager).

partman-md

- Allows the user to set up Software RAID (Redundant Array of Inexpensive Disks). This Software RAID is usually superior to the cheap IDE (pseudo hardware) RAID controllers found on newer motherboards.

base-installer

- Installs the most basic set of packages which would allow the computer to operate under &debian-gnu; when rebooted.

apt-setup

- Configures apt, mostly automatically, based on what media the installer is running from.

pkgsel

- Uses `tasksel` to select and install additional software.

os-prober

- Detects currently installed operating systems on the computer and passes this information to the bootloader-installer, which may offer you an ability to add discovered operating systems to the bootloader's start menu. This way the user could easily choose at the boot time which operating system to start.

bootloader-installer

- The various bootloader installers each install a boot loader program on the hard disk, which is necessary for the computer to start up using &arch-kernel; without using a USB stick or CD-ROM. Many boot loaders allow the user to choose an alternate operating system each time the computer boots.

shell

- Allows the user to execute a shell from the menu, or in the second console.

save-logs

- Provides a way for the user to record information on a USB stick, network, hard disk, or other media when trouble is encountered, in order to accurately report installer software problems to &debian; developers later.

&using-d-i-components.xml; &loading-firmware.xml; &customization.xml;