Debian Linux remove unwanted packages and files to reclaim disk space

After few months or years later, you will notice unnecessary files, libraries and/or documentation eating up your disk space under Debian Linux. Try the following tips to free up disk space:

Remove cached .deb files

When you run apt-get command, it downloads and caches the package in /var/cache/apt/archives directory.
# cd /var/cache/apt/archives # du –ch
Output:

8.0K    ./partial
838M    .
838M    total

Next remove all cached *.deb files:
# rm –f *.deb

Remove Orphaned package

deborphan command finds packages that have no packages depending on them. The default operation is to search only within the libs and oldlibs sections to hunt down unused libraries.

Following command displays Orphaned package list:
$ deborphan -sz
Where,

-s: Show the sections the packages are in.
-z: Show the installed size of the packages found.

You can remove orphaned package with apt-get remove command:
# apt-get remove packagename
Alternatively, remove all orphaned package in one command:
# apt-get remove $(deborphan)
Better try:
# apt-get remove --purge $(deborphan)

If you find command line hard to use try orphaner command which is nothing but a neat frontend for deborphan displaying a list of orphaned packages with dialog or whiptail. Packages may be selected for removal with apt-get which is then called to do the work. After removal a new list of orphaned packages is gathered from deborphan. The program ends when either "Cancel" is pressed or no package is marked for removal.
# orphaner

(Fig 01: orphaner command in action )

However some packages are important and if you want to keep them forever, use editkeep command which is a frontend for deborphan displaying a list of orphaned packages (-a for all-sections is implied) and packages which are tagged to never been shown using dialog or whiptail:
# editkeep

cruft command

cruft is a program that goes over the Debian packaging system's database, and compares the contents of that with the files actually on your system, and produces a summary of the differences. For example, you can clean spool with following command:
# cruft –k

Read the cruft man page for advance usage.