For installing on multiple computers it's possible to do fully automatic installations using the Ubuntu Installer itself.
The Ubuntu Installer supports automating installs via preconfiguration files. A preconfiguration file can be loaded from the network or from removable media, and used to fill in answers to questions asked during the installation process.
Full documentation on preseeding including a working example that you can edit is in Appendix B, Automating the installation using preseeding.
The Ubuntu installer has preliminary support for automating installs using Kickstart files, as designed by Red Hat for use in their Anaconda installer. This method is not as flexible as the preconfiguration file method above, but it requires less knowledge of how the installer works.
This section documents only the basics, and differences between Anaconda and the Ubuntu installer. Refer to the Red Hat documentation for detailed instructions.
To generate a Kickstart file, install the
system-config-kickstart
package and run
system-config-kickstart
. This offers you a graphical
user interface to the various options available.
Once you have a Kickstart file, you can edit it if necessary, and place it on a web, FTP, or NFS server, or copy it onto the installer's boot media. Wherever you place the file, you need to pass a parameter to the installer at boot time to tell it to use the file.
To make the installer use a Kickstart file downloaded from a web or FTP server, add ks=http://url/to/ks.cfg or ks=ftp://url/to/ks.cfg respectively to the kernel boot parameters. This requires the installer to be able to set up the network via DHCP on the first connected interface without asking any questions; you may also need to add ksdevice=eth1 or similar if the installer fails to determine the correct interface automatically.
Similarly, to make the installer use a Kickstart file on an NFS server, add ks=nfs:server:/path/to/ks.cfg to the kernel boot parameters. The method supported by Anaconda of adding a plain "ks" boot parameter to work out the location of the Kickstart file from a DHCP response is not yet supported by the Ubuntu installer.
To place a Kickstart file on a CD, you would need to remaster the ISO image to include your Kickstart file, and add ks=cdrom:/path/to/ks.cfg to the kernel boot parameters. See the manual page for mkisofs for details. Alternatively, put the Kickstart file on a floppy, and add ks=floppy:/path/to/ks.cfg to the kernel boot parameters.
The Ubuntu installer supports a few extensions to Kickstart that were needed to support automatic installations of Ubuntu:
The rootpw
command now takes the
--disabled
option to disable the root password. If
this is used, the initial user will be given root privileges via
sudo
.
A new user
command has been added to control the
creation of the initial user:
user joe
--fullname "Joe User" --password iamjoe
The --disabled
option prevents any non-root users
from being created. The --fullname
option specifies
the user's full name, as opposed to the Unix username. The
--password
option supplies the user's password, by
default in the clear (in which case make sure your Kickstart file is kept
confidential!); the --iscrypted
option may be used to
state that the password is already MD5-hashed.
A new preseed
command has been added to provide a
convenient way to preseed additional items in the debconf database that are
not directly accessible using the ordinary Kickstart syntax:
preseed --owner gdm shared/default-x-display-manager select gdm
Note that if the value contains any special characters, then the value must be quoted, as follows:
preseed preseed/late_command string "sed -i 's/foo/bar/g' /target/etc/hosts"
The --owner
option sets the name of the package that
owns the question; if omitted, it defaults to d-i, which is generally
appropriate for items affecting the first stage of the installer. The three
mandatory arguments are the question name, question type, and answer, in
that order, just as would be supplied as input to the
debconf-set-selections
command.
As of Ubuntu 6.10, the keyboard
option takes X layout
names. To use an X keyboard variant, set this option to
layout_variant
, with appropriate values of
layout
and variant
. For
example, in_guj
selects the Gujarati variant of the
Indian layout.
You may use the apt-install command to install packages
in %post --nochroot
scripts (although you might also
choose to generate a %packages
section in a
%pre
script and include it using
%include
). Note that this does not work if the
post-installation script is run in the chroot environment.
As yet, the Ubuntu installer only supports a subset of Kickstart's features. The following is a brief summary of features that are known to be missing:
LDAP, Kerberos 5, Hesiod, and Samba authentication.
The auth --enablecache
command to enable
nscd
.
The bootloader --linear
,
--nolinear
, and --lba32
options for detailed LILO configuration.
Upgrades. To upgrade from one Ubuntu release to another, use the facilities
provided by apt
and its frontends.
Partitioning of multiple drives. Due to current limitations in the partition manager, it is only possible to partition a single drive.
Using the device
command to install extra kernel
modules.
Driver disks.
Firewall configuration.
Installation from an archive on a local hard disk or from an NFS archive.
The lilocheck
command to check for an existing LILO
installation.
The logvol --percent
,
--bytes-per-inode
, and
--fsoptions
options for certain kinds of detailed
Logical Volume Management (LVM) configuration. (LVM configuration in general
is experimentally supported as of Ubuntu 9.04; please let us know about your
experiences with it.)
Restrictions of a partition to a particular disk or device, and specifications of the starting or ending cylinder for a partition.
Checking a partition for bad sectors.
RAID configuration.
The xconfig --monitor
option to use a specified
monitor name.
Most package groups. As special cases, the "Ubuntu Desktop" and "Kubuntu Desktop" groups install the standard Ubuntu or Kubuntu desktop systems respectively, and any group name not containing a space (for example, "ubuntu-desktop") causes packages with the corresponding Task: header in the Packages file to be installed.
Exclusions in %packages sections are no longer supported as of Ubuntu 6.10, as a casualty of other improvements. You may need to use a %post script instead to remove unnecessary packages.
Pre-installation scripts and non-chrooted post-installation scripts may only be shell scripts; other interpreters are not available at this point in the installation.