Advice For New Users On Not Breaking Their Debian System
Debian is a robust and reliable system, but it's still very easy for new users to break their systems by not doing things the Debian way. This page lists common mistakes made by new users. Some of the things listed here can be done safely, but only if you have enough experience to know how to fix your system when things go wrong.
The general theme to the advice here is that consequences are not always immediate, and can make future upgrades impossible without a complete reinstall. If upgrading without a complete reinstall is important to you, be careful not to make the mistakes outlined below.
One of the primary advantages of Debian is its central repository with thousands of software packages. If you're coming to Debian from another operating system, you might be used to installing software that you find on random websites. On Debian installing software from random websites is a bad habit. It's always better to use software from the official Debian repositories if at all possible. The packages in the Debian repositories are known to work well and install properly. Only using software from the Debian repositories is also much safer than installing from random websites which could bundle malware and other security risks.
Advice For New Users On Not Breaking Their Debian System
- Don't make a FrankenDebian
- Don't use GPU manufacturer install scripts
- Don't suffer from Shiny New Stuff Syndrome
- Don't 'make install'
- Don't blindly follow bad advice
- Don't forget to read the documentation
- Don't blindly remove software
- Don't install without reading descriptions
- Don't forget to take notes!
- Don't have poor etiquette when getting support!
- See Also
Don't make a FrankenDebian
Debian Stable should not be combined with other releases. If you're trying to install software that isn't available in the current Debian Stable release, it's not a good idea to add repositories for other Debian releases. The problems might not happen right away, but the next time you install updates.
The reason things can break is because the software packaged for one Debian release is built to be compatible with the rest of the software for that release. For example, installing packages from Jessie on a Wheezy system will also install newer versions of core libraries including glibc. This results in a system that is not Wheezy or Jessie but a broken mix of the two.
Repositories that can create a FrankenDebian if used with Debian Stable:
Debian testing release (currently stretch)
Debian unstable release (also known as sid)
Ubuntu, Mint or other derivative repositories are not compatible with Debian!
- Ubuntu PPAs
Don't use GPU manufacturer install scripts
Debian includes Free open source drivers that support most video cards. The Free drivers provide the best integration with the rest of the Debian system and work quite well for most users.
If you absolutely must have the proprietary closed source drivers, do not download them directly from the manufacturer's website!. Installing drivers this way only works for the current kernel, and after the next kernel update your video drivers will not work until they are manually reinstalled again.
Fortunately there is a Debian way to install proprietary video card drivers using packages in the repository. Installing the drivers the Debian way will make sure that the drivers continue to work after kernel updates.
AtiHowTo has instructions on using the Free open source drivers for ATI/AMD video cards.
ATIProprietary has instructions for installing ATI/AMD closed source drivers the Debian way.
NvidiaGraphicsDrivers has instructions for installing Nvidia closed source drivers the Debian way.
Don't suffer from Shiny New Stuff Syndrome
The reason that Debian Stable is so reliable is because software is extensively tested and bug-fixed before being included. This means that the most recent version of software is often not available in the Stable repositories. But it doesn't mean that the software is too old to be useful!
Before attempting to install the newest version of some software from somewhere other than the Debian Stable repositories, here are some things to keep in mind:
- Debian backports security fixes and new features, judging software by comparing the version number of the Debian package to the upstream version number does not take this into account.
- The latest version of the software you're trying to use might also have new bugs.
- Installing software from places other than official Debian repositories might not get security updates.
Sometimes newer versions are available from https://backports.debian.org/.
Those wishing to assume more risk and responsibility can sometimes make their own backports of the latest Debian software. While not without risk, self-backporting is usually safer than other approaches. When self-backporting fails it is likely that any other approach will break your system. Instructions are available through one of the Debian IRC bots (as are instructions for self-backporting the very latest from the software's authors). The judd IRC bot provides the checkbackport command to provide some guidance as to whether backporting is possible. You may wish to consult on IRC or elsewhere to investigate the risks and rewards of self-backporting.
Don't 'make install'
It's quite easy to compile software from source code tarballs downloaded from the software's website, but not always so easy to remove it later. Often the instructions that come with the source code include instructions to use commands like ./configure && make && make install.
When you install software this way, you will not be able to remove it with apt-get or Synaptic. The APT packaging system can only remove software that was installed by the APT packaging system. Even worse, software installed this way can sometimes conflict with the software packaged for Debian.
Software installed this way also does not benefit from security updates the way that Debian packages do. If you want to keep your system up to date without having to manually compile and reinstall for every update, stick to the Debian packages.
What can happen, and why it's bad
The make install script may make invalid assumptions about where the compiled binary and its associated files should exist in the filesystem and under what set of permissions / ownership it should run. Software installed with excessively high privilege on your system can cause errors and data loss.
How to avoid problems
- If you are building software from source obtained otherwise than from Debian, it's a good idea to build and run it as a normal user, within that user's home directory. If you keep sensitive, valuable, or non-replaceable data in your home directory, it might be a good idea to create another user account for this purpose.
automake, and other build systems, can install self-built software in non-standard locations. It is a bad idea to be root or use "sudo" to install self-built software into /usr/bin or the other standard locations where regular packages place files. It is almost always possible to instead install into your home directory instead. (Using ./configure --prefix=~/.local or similar.) If you understand how to edit Makefiles, then you can alter the makefile in such a way as to render make install useful for your system or add a prefix=~/.local option.
Another good choice is to use the /usr/local/ hierarchy for installation of unpackaged software. The stow package can be useful in managing this.
You can avoid the make install script by using CheckInstall. It will install the software and will give you the ability to uninstall it with your distribution's standard package management utilities.
Don't blindly follow bad advice
Unfortunately there's a lot of bad advice on the Internet. Tutorials found on blogs, forums and other sites often include instructions that will break your system in subtle ways. Don't simply follow the first advice you find, or the tutorial that seems the easiest. Spend some time reading the documentation and compare the difference between tutorials.
It's better to take the time to figure out the correct way to do something first than spending even more time fixing a broken system later. You would not let some random stranger feed your baby; do not execute commands without first understanding what they do.
Blog and forum posts don't expire. Instructions that might have been safe a couple of years ago might not be safe to follow any more. When in doubt keep researching and read your version's documentation.
Don't forget to read the documentation
Often reading a tutorial is only enough to get a general idea of how to install or use an application. Almost all of the software packaged for Debian has at least some documentation available. Some places to look:
The Debian documentation homepage: https://www.debian.org/doc/
The Debian Administrator's Handbook: https://debian-handbook.info/
The apropos command will help you find manual pages.
The man command for reading the manual pages for commands you don't understand.
Some software has a separate <package name>-doc package containing documentation.
Every Debian package installed on your system has a directory in /usr/share/doc that will often contain a README.Debian file with information about differences from the upstream version of the software along with additional documentation.
Don't blindly remove software
Sometimes when you remove a package, the package manager needs to remove other packages too. This is because the additional packages depend on the package you're trying to remove.
If this happens, the package manager will show you a list everything that will be removed and ask for your confirmation. Make sure to read this list carefully! If you don't know what some of the packages to be removed are for, read the descriptions for each one. When in doubt, do more research. Some resources that can help you understand what packages are for include:
apt-cache show <package name> on the command line
Don't install without reading descriptions
It's also wise to read the descriptions of packages before installing them. Sometimes software will have different packages available in the Debian repository, with each package configured a different way. Read the package descriptions and search for similar package names to make sure you get the one you want.
This point can be especially important for packages that install kernel modules.
Don't forget to take notes!
It's easy to forget the steps you took to do something on your computer, especially several months later when you're trying to upgrade. Sometimes when you try several different ways of solving a problem, it's easy to forget which method was successful the next day!
It's a very good idea to take notes about the software you've installed and configuration changes you've made. When editing configuration files, it's also a very good idea to include comments in the file explaining the reason for the changes and the date they were made.
Don't have poor etiquette when getting support!
When looking for support it's important to remember that Debian is a volunteer project and people will be more inclined to help if you're polite and willing to put a little effort in yourself. Here are some general guidelines that will help you get help:
- Research the issue on your own first, including reading documentation and using search engines.
Provide details and ask smart questions: http://www.catb.org/~esr/faqs/smart-questions.html.
- If you get frustrated don't take it out on the volunteers trying to help, even if they seem frustrated with you.
- Don't expect to be spoon fed, if you need to be guided through step by step it's a sign that you need to learn more on your own by reading documentation.
- On IRC especially:
Don't hit <enter> every few words it gets hard to follow.
- Wait around for a response, people often disappear just before someone answers their question.
Use https://paste.debian.net/ instead of pasting directly into the channel.