Upgrade of software
1. How to know when you need to upgrade
there are several ways you can learn about security issues. the most common way would be to subscribe to the Debian Security Announce email list. This is a low volume list that you realy should read if you feel resposible for a Debian-Edu/Skolelinux system. But not all packages in Debian-Edu are in Debian. So Debian-Edu have their own security advisories for their uniqe packages. to be alterted about those you can join one of the project mailinglists or your native language userlist.
A different aproch might be to run apticon or cron-apt and have those email you needed upgrades. Note that it's not very clever to let scripts do your upgrades. Since you usualy want to be the first to know when a packages overwrites your configuration.
The final and most unpleasant way is when your system is hijacked and you get notices from your ISP about your servers participating in spam runs, ddos attacks, acts as a storage for illegal files, or all of the above.
2. How do I keep my server up-to-date with Security Updates?
Make sure that the file /etc/apt/source.lists contains the line
deb http://security.debian.org/ etch/updates main contrib non-free
which tells APT (the Advanced Package Tool) to look for new packages on the security.debian.org website. Regularly run these two commands:
apt-get update apt-get upgrade
The first command (update) downloads the list of available packages in the configured apt sources. The second command (upgrade) checks if any packages are out of date and upgrades them if necessary. This automatically keeps all of your packages up-to-date including security patches. You may also like to join the Debian Security Announcement mailing list, to get an email whenever a security update is released.
3. What must I place in /etc/apt/source.lists in order that I can install packages from the Debian software archive? The server in Norway contains a complete Debian Mirror. Therefore all you must do is remove the CD-ROM lines (used during installation) and uncomment (remove the preceding # symbol from) the deb lines in the source list.
# security updates # deb http://security.debian.org/ etch/updates main contrib non-free # # Skolelinux debian packages # deb http://ftp.skolelinux.no/debian etch main non-free contrib
It might be wise to consider using your local debian mirror for the debian repository if you'r located outside of norway. You can find them all at the Debian mirror list
A functioning Internet connection is a requirement for this to work.