The boot loader on S/390 is ``zipl''. ZIPL is similar in
configuration and usage to LILO, with a few exceptions. Please
take a look at ``LINUX for S/390 Device Drivers and Installation Commands''
from IBM's developerWorks web site if you want to know more about
ZIPL.
You system's first boot on its own power is what electrical engineers call the ``smoke test''. Select the ``Reboot the System'' menu item which will halt the system because rebooting is not supported on S/390 in this case. You then need to IPL GNU/Linux from the DASD which you selected for the root filesystem during the first steps of the installation.
Debian should boot, and you should see the same messages as when you first booted the installation system, followed by some new messages.
After booting, you will be prompted to complete the configuration of your basic
system, and then to select what additional packages you wish to install. The
application which guides you through this process is called
base-config. If you wish to re-run the base-config
at any point after installation is complete, as root run
base-config.
You will first be prompted to configure your time zone. After selecting local vs. GMT hardware clock setting, you will select a region and then a city within that region which is in the same time zone you are. When making selections in these lists, you can type a single letter to take you to the section of the list beginning with that letter.
You will next be prompted whether to install MD5 passwords. This is an alternate method of storing passwords on your system which is more secure than the standard means (called ``crypt'').
The default is ``No'', but if you do not require NIS support and are very concerned about security on this machine, you may say ``Yes''.
Unless you said ``Yes'' to MD5 passwords, the system will ask whether you want
to enable shadow passwords. This is a system in which your GNU/Linux system is
made to be a bit more secure. In a system without shadow passwords, passwords
are stored (encrypted) in a world-readable file, /etc/passwd.
This file has to be readable to anyone who can log in because it contains vital
user information, for instance, how to map between numeric user identifiers and
login names. Therefore, someone could conceivably grab your
/etc/passwd file and run a brute force attack (i.e. run an
automated test of all possible password combinations) against it to try to
determine passwords.
If you have shadow passwords enabled, passwords are instead stored in
/etc/shadow, which is readable and writable only by root, and
readable by group shadow. Therefore, we recommend that you enable shadow
passwords.
Reconfiguration of the shadow password system can be done at any time with the
shadowconfig program. After installation, see
/usr/share/doc/passwd/README.debian.gz for more information.
The root account is also called the super-user; it is a login that bypasses all security protection on your system. The root account should only be used to perform system administration, and only used for as short a time as possible.
Any password you create should contain from 6 to 8 characters, and should contain both upper- and lower-case characters, as well as punctuation characters. Take extra care when setting your root password, since it is such a powerful account. Avoid dictionary words or use of any personal information which could be guessed.
If anyone ever tells you they need your root password, be extremely wary. You should normally never give your root account out, unless you are administering a machine with more than one system administrator.
The system will ask you whether you wish to create an ordinary user account at this point. This account should be your main personal log-in. You should not use the root account for daily use or as your personal login.
Why not? Well, one reason to avoid using root's privileges is that it is very easy to do irreparable damage as root. Another reason is that you might be tricked into running a Trojan-horse program — that is a program that takes advantage of your super-user powers to compromise the security of your system behind your back. Any good book on Unix system administration will cover this topic in more detail — consider reading one if it is new to you.
Name the user account anything you like. If your name is John Smith, you might use ``smith'', ``john'', ``jsmith'' or ``js''. You will also be prompted for the full name of the user, and, like before, a password.
If at any point after installation you would like to create another account,
use the adduser command.
You need to create a user account on S/390 if you want to login over the network using telnet. The telnet server does not allow root logins in Debian's default configuration. However, you can use ssh (Secure SHell) to remotely login as root but this is not recommended.
The main means that people use to install packages on their system is via a
program called apt-get, from the apt package.[4] APT must be configured, however,
so that it knows where to retrieve packages from. The helper application which
assists in this task is called apt-setup.
The next step in your configuration process is to tell APT where other Debian
packages can be found. Note that you can re-run this tool at any point after
installation by running apt-setup, or by manually editing
/etc/apt/sources.list.
If you are booting from an official CD-ROM, then that CD-ROM should automatically be configured as an apt source without prompting. You will notice this because you will see the CD-ROM being scanned, and then asked if you want to configure another CD-ROM. If you have a multiple CD-ROM set — and most people will — then you should go ahead and scan each of them one by one.
For users without an official CD-ROM, you will be offered an array of choices for how Debian packages are accessed: FTP, HTTP, CD-ROM, or a local file system. For CD-ROM users, you can get to this step by specifically asking to add another source.
You should know that it's perfectly acceptable to have a number of different
APT sources, even for the same Debian archive. apt-get will
automatically pick the package with the highest version number given all the
available versions. Or, for instance, if you have both an HTTP and a CD-ROM
APT source, apt-get should automatically use the local CD-ROM when
possible, and only resort to HTTP if a newer version is available there.
However, it is not a good idea to add unnecessary APT sources, since this will
tend to slow down the process of checking the network archives for new
versions.
If you plan on installing the rest of your system via the network, the most common option is to select the ``http'' source. The ``ftp'' source is also acceptable, but tends to be a little slower making connections.
Next you will be asked whether you wish to have any non-free software. That
refers to commercial software or any other software whose licensing does not
comply with the Debian Free Software
Guidelines. It's fine to say ``Yes'', but be careful when
installing such software, because you will need to ensure that you are using
the software in compliance with its license.
The next step during the configuration of network packages sources is to tell
apt-setup which country you live in. This configures which of the
official Debian Internet mirror network you connect to. Depending on which
country you select, you will be given a list of possible machines. Its
generally fine to pick the one on the top of the list, but any of them should
work.
If you are installing via HTTP, you will be asked to configure your proxy server. This is sometimes required by people behind firewalls, on corporate networks, etc.
Finally, your new network package source will be tested. If all goes well, you will be prompted whether you want to do it all over again with another network source.
You will next be prompted whether you wish to install packages the simple way, or the more fine-grained, advanced way. We recommend you start with the simple way, since you can always run the more advanced way at any time.
You should know that for simple installation, base-config is
merely invoking the tasksel program. For advanced package
installation, the dselect program is being run. Either of these
can be run at any time after installation to install more packages. If you are
looking for a specific single package, after installation is complete, simply
run apt-get install package, where package
is the name of the package you are looking for.
If you chose ``simple'' installation, you will next be thrown into the Task
Installer (tasksel). This technique offers you a number of
pre-rolled software configurations offered by Debian. You could always choose,
package by package, what you want to install on your new machine. This is the
purpose of the dselect program, described below. But this can be
a long task with around 8100 packages available in Debian!
So, you have the ability to choose tasks first, and then add on more individual packages later. These tasks loosely represent a number of different jobs or things you want to do with your computer, such as `desktop environment', `development in C', or `file server'.
For each task, you can highlight that task and select ``Task Info'' to see more information on that task. This will show you an extended description and the list of packages which will be installed for that task. A table showing approximate sizes of the various tasks for planning purposes is in Disk Space Needed for Tasks, Section 11.4.
Once you've selected your tasks, select ``Finish''. At this point,
apt-get will install the packages you've selected. Note, if you
did not select any tasks at all, any standard, important, or required priority
packages that are not yet present on your system will be installed. This
functionality is the same as running tasksel -s at the command line, and
currently involves a download of about 37M of archives. You will be shown the
number of packages to be installed, and how many kilobytes of packages, if any,
need to be downloaded.
Of the 8100 packages available in Debian, only a small minority are covered by
tasks offered in the Task Installer. To see information on more packages,
either use apt-cache search search-string for some
given search string (see the apt-cache(8) man page), or run
dselect as described below.
dselect
If you selected ``advanced'' package selection, you'll be dropped into the
dselect program. The dselect Tutorial is required reading
before you run dselect. dselect allows you to select
packages to be installed on your system. You must be the super-user
(root) when you run dselect.
Each package you selected with either tasksel and/or
dselect is unpacked and then installed in turn by the
apt-get and dpkg programs. If a particular program
needs more information from the user, it will prompt you during this process.
You might also want to keep an eye on the output during the process, to watch
for any installation errors (although you will be asked to acknowledge errors
which prevented a package's installation).
After you've installed packages, you'll be presented with the login prompt. Log in using the personal login and password you selected. Your system is now ready to use.
If you are a new user, you may want to explore the documentation which is already installed on your system as you start to use it. There are currently several documentation systems, work is proceeding on integrating the different types of documentation. Here are a few starting points.
Documentation accompanying programs you have installed is in
/usr/share/doc/, under a subdirectory named after the program.
For example, the APT User's Guide for using apt to install other
programs on your system, is located in
/usr/share/doc/apt/guide.html/index.html.
In addition, there are some special folders within the
/usr/share/doc/ hierarchy. Linux HOWTOs are installed in .gz
format, in /usr/share/doc/HOWTO/en-txt/ and
/usr/share/doc/HOWTO/en-txt/mini/. The
/usr/share/doc/HTML/index.html contains browse-able indexes of
documentation installed by dhelp.
One easy way to view these documents is to cd /usr/share/doc/, and type lynx followed by a space and a dot (the dot stands for the current directory).
You can also type info (command) or man (command) to see documentation on most commands available at the command prompt. Typing help will display help on shell commands. And typing a command followed by --help will usually display a short summary of the command's usage. If a command's results scroll past the top of the screen, type | more after the command to cause the results to pause before scrolling past the top of the screen. To see a list of all commands available which begin with a certain letter, type the letter and then two tabs.
For a more complete introduction to Debian and GNU/Linux, see
/usr/share/doc/debian-guide/html/noframes/index.html.
Installing Debian GNU/Linux 3.0 For S/390
version 3.0.23, 16 May, 2002