Having your our own Debian/Ubuntu Linux Mirror enables you to drastically speed up the process of installing packages or complete netbuilds on your single or networked Linux PC (s).
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Using the following tutorial, the same method can be used for building a Ubuntu Mirror if desired.
Note: This process was tested using both Debian Etch and Lenny. If step 2 fails to find and install the apt-mirror package, you may need to add the following line to your /etc/apt/sources.list