APT provides an effective way of installing packages and programs. Default settings are created and in some cases default users are created for managing the services and/or programs. APT handles all shared modules, dependencies and libraries of tools. When installing a program via APT - the default locations within Linux (Debian) should be consulted.<br>The following directories are where files are stored after APT - and are mostly default:<br> /etc/* → stores all scripts (/etc/init.d = Startup Scripts)<br> /var/* → stores things such as temp, logs, www, mail, backups, libraries etc.<br> /usr/* → stores bin files which can be executed using ./<br> /home/* → stores all user home files.<br> <br>

To download Updates and All Package Information for Debian Sarge apt-get update

To upgrade All Packages and Sources apt-get upgrade and/or apt-get install

To Install an Individual Package apt-get install package

To Remove an Individual Package apt-get remove package

To Show Information on a Particular Package apt-cache show package

To Search for New Packages (apart from web search) apt-cache search package

APT runs ontop of dpkg (front end) - a Package Manager To List Packages and perform more detailed operations: dpkg -l or dpkg -l | grep package<br> <br>

Even though APT is meant to provide an effective way to install packages etc., problems were experienced. Problems arose due to incorrect apt-get installing in the beginning and also due to suggests etc. with mail.<br> Pine was initially installed. Postfix and Courier were installed then. Pine suddenly dropped off, or was uninstalled due to dependancies & incomplete knowledge of what was happening. Care MUST be taken with apt. What was done in this case to fix pine, was to download a .deb package from the pine homepage. It was installed via:<br> dpkg -i package.deb <br>Another related problem is the fact that Horde does not want to install via apt-get after Mailserver install and config.<br> edit: Dont know if pine is available via apt-get due to licencing issues

apt config is located at: /etc/apt<br> 1. The following is required if using a proxy server to access the internet: apt.conf (May have to write a new file) Acquire::http::Proxy “http://proxy:port”;

2. To obtain apt packages fast from the nearest mirror (should be done from initial set-up) sources.list can be edited. It is also determined whether to use “STABLE” or “TESTING” apt source packages. sources.list (Should be OK as is) deb http://ftp.ie.debian.org/debian/ stable main deb-src http://ftp.ie.debian.org/debian/ stable main

Instead of Configuring Step 1. for using a Proxy server, an environment variable can also be set. This is useful if using links or a text based browser.<br> <root@debian»~$ export http_proxy=“http://proxy:port”

The following is taken from an excellent article on this: http://jaqque.sbih.org/kplug/apt-pinning.html

Include both stable and testing sources to /etc/apt/sources.list

vi /etc/apt/sources.list

deb http://ftp.de.debian.org/debian/ stable main deb http://ftp.de.debian.org/debian/ testing main

vi /etc/apt/preferences

Package: * Pin: release a=stable Pin-Priority: 700

Package: * Pin: release a=testing Pin-Priority: 650

Package: * Pin: release a=unstable Pin-Priority: 600

Thats it. apt-get install package (works as normal taking stable first) apt-get -t testing install <package> #or apt-get install <package>/unstable

dpkg is a very useful tool for getting a bit more hands-on with debian packages.

dpkg -i package.deb //generally the .deb can be downloaded from debian.org

dpkg -L package

Taken from: http://maketecheasier.com/become-an-apt-guru/2009/02/24/

dpkg -S /etc/mysql/my.cnf #shows which package created a particular file.

dpkg -L mysql-common #list all files associated with a particular package.

aptitude hold (packagename) echo “(packagename) hold” | dpkg –set-selections #both these do the same thing, i.e. prevent a package from been updated.