Deploying Debian GNU/Linux with ICE-Linux

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The Debian GNU/LINUX Distribution
Debian® GNU/Linux is a collection of GNU applications compiled and distributed with the Linux®
kernel. Together they are called a dist, or distribution, of the Linux operating system.
Debian GNU/Linux is unique. It is among the most complex of the Linux distributions because of its
flexibility in providing distributions for other hardware architectures and operating system kernels. It
also standardizes software packaging on all these hardware platforms and kernels while deliberately
presenting the least amount of upstream source code management and code customization. Both the
upstream source code maintainers and the users of code from a particular source are often most
familiar with the defaults provided for their code.
Therefore, there are few surprises when installing a Debian Linux software package. It generally just
works the way the programmer intended and works identically on different hardware platforms and
under different kernels.
So while Debian provides maximum flexibility and a minimal approach to software management, it
does provide a means for collecting useful information from a user when a software package is
installed.
Optionally, when a software package is created for a Debian distribution, it can include a list of
questions or a template for the debconf system and a script for asking those questions. Despite its
name, debconf is not a management or configuration system. It provides a means for a software
package maintainer or writer to supply a series of questions for a user in a common user interface
when a software package is installed. The debconf system does not use the answers to configure a
software package, rather the answers are saved into the debconf database and can be referenced
by a software packages install script, if the maintainer or software package writer so chooses.
Debian Mirrors
Using an analogy, Debian is a huge spinning accretion disk like that surrounding a large black hole.
It tends to absorb the code from other projects and pack them into packages for distribution. The
Debian logo is a spinning spiral, which even suggests as much.
To make the collection and distribution of Debian possible, it is founded on the concept of a
distribution mirror, which is a common place to collect and share software packages. Local Mirrors
are copies of all the shared files from one machine to another on the Internet.
Debian organizes its mirror in a particular way to make sharing the files easier.
First, Debian recognizes that a mirroring program needs a list of files to copy, so it provides index
files of all the files for a particular purpose and where there are located on the server. These index
files are kept in directories named for their purpose. For example, the index files for Debian 3.0 are
kept in the Debian3.0 directory, and the index files for Debian 4.0 are kept in the Debian4.0
directory. A mirroring program that wants to copy only the files for Debian 4.0 downloads the index
files for Debian 4.0, and uses those files to fetch and create its local copies.
To avoid recopying the index files, the index file directories are kept in a directory named dists and
the software packages are kept in a directory named pools. The software packages in pools are
arranged in directories alphabetically beginning with the first letter in the software package name. So
the
a/ directory could have packages for Debian 3.0 and Debian 4.0, but the index files know
which packages are appropriate for the corresponding distribution.