Ubuntu Linux--Would You Like Some Community With That?
Installing Ubuntu

Bill von Hagen
Thursday, February 3, 2005 08:03:37 PM
This section focuses on the default 4.10 (Warty) installation
process. Installation is largely a misnomer for the Hoary live CDs,
which boot and run from CD on an existing system without disturbing
anything that's already there (though they will take advantage of
existing swap partitions). Live CD "installs" still prompt for some
information, such as the language and keyboard layout that you want to
use, and do so in the same interactive framework as when installing
Ubuntu to disk.
By default, Ubuntu installs a desktop system centered around the GNOME
desktop. Server-type or custom-hardware installs are still possible
through the extensive options that you can read about by pressing F1
at the initial Ubuntu install screen. For example, to install a
minimal system, you specify "custom" at the initial prompt and must
then bypass automatic updates later on in the install. This will give
you a basic, command-line system that you can tweak to your heart's
content using apt-get before breaking out your collection of VT100s or
H19s.
After pressing Return to begin my initial Ubuntu 4.10 install, I
immediately thought I was having a flashback to Yggdrasil days
(http://en.wikipedia.org/wiki/Yggdrasil_Linux) or was accidentally
installing Slackware. See Figure 1 for a shot of one of the
4.10 installation dialogs. Luckily, at that point, the epiphany
occurred and I realized that my mind had been warped by graphical
bells and whistles. What I was actually seeing "what I needed to see."
An interesting concept--a modern Linux distribution that serves people
who might not have 256MB video cards and a Terabyte of disk
space. Even my toaster has SVGA nowadays, but it's still nice to see
an installer that will easily work on 32-bit PC hardware of almost any
vintage.
Warty's installation process is a two-phase process. The first
captures basic information about the language and keyboard layout that
you want to use, and then probes and configures your system's
hardware. It provides its own disk partitioner, which supports ext2,
ext3, ReiserFS, JFS, XFS, and FAT16 and FAT32 filesystems, as well as
software RAID and logical volumes. By default, the partitioner creates
a single swap partition and a single ext3 filesystem. The partitioner
can be a tad confusing if you opt for manual partitioning, but works
nicely once you get the hang of it.
After partitioning the disk, the installer installs the base system,
copies remaining packages to the disk, installs GRUB, and then ejects
the CD and reboots into the second phase of the installer. The second
phase installer enables you to create the system's default user and
then installs the packages that were formerly cached to disk and,
optionally, updates to those packages over the net. Figure 2 shows
a sample screen of the vast number of package installs during the
second phase of the installer. GUI-lovers, avert your eyes!
Unique to Ubuntu and "Live" distributions such as Knoppix is the fact
that you do not create a superuser account or set a superuser
password. In Ubuntu, the user whose account you create during the
second phase of the install process has the ability to run "execute as
root" process (using sudo under the covers) and can even start a root
shell in a terminal window from one of the desktop menus. Figure 3
shows the type of dialog that displays whenever you attempt to execute
an application that uses root privileges. Because Ubuntu is using sudo
under the covers, the password that you must type is the password of
the user that is currently logged in--typically yourself. Frankly,
this is somewhat confusing for many people since you are already
logged in as that user, but this is the wrong place for a discussion
of the history and implementation of Linux/Unix security mechanisms
and ways of maintaining backward compatibility.
If you're using Ubuntu in a commercial setting, the implications of
giving normal users the ability to run privileged commands requires
some sysadmin forethought. It requires a significant amount of trust
in anyone with physical access to anyone else's system, but it is a
great way to discourage people from asking for or using the root
account when it isn't actually necessary. Whether or not sudo is a
complete replacement for root access on an installed systems is a
philosophical discussion that is scheduled to complete shortly after
the vi/emacs flames wars finish.
Next: What's in the Box »