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Package Management Tools

For those people who reside inside the United States, several important pack 

ages are not available from US servers because of cryptographic laws there.

These packages can be legally obtained by US citizens from servers outside the

US, so if you want access to these packages you will need to add another line

specifying that server and the section you wish to access.

Updating Packages Files

When the system is installed using CDROMs, the Packages file is read from

each CD inserted during the installation process. These files are used to update

the apt database so that apt get will be able to find the packages it is asked to

install. For the 2.2 release this amounted to 4 binary CDs when the complete

archives is included, providing over 4000 packages.

Under these circumstances you will not need to update the apt get database

again until you are ready to use a new release set of CDs. Then you will use

the command apt get update, and insert the new CDs when requested. This

will bring the database up to date with the packages on the new CDs.

If you use an FTP archives of Debian to maintain your new system in the

future, you only need to do an update whenever the archives changes. For the

stable release this is quite rare, although it does happen, making it useful to

keep track of the latest update release for stable. Running update when the

release changes will keep your system up to date with the archives.

If apt get's sources.list file references the unstable distribution, you will prob 

ably need to run update each time you wish to upgrade your system. Since

the unstable distribution changes often, and without notice, this is the only

way to keep in sync with the archives.