Overzealous Configuration Tools

Another class of problems relates to configuration tools that are overzealous in one way or another. Typically, these tools overwrite existing configuration files without just cause, and sometimes without asking you whether it's acceptable to do so. One common source of such problems is upgrading software packages, and especially servers and other system software. For instance, you may have spent hours creating the ideal Apache web server configuration. When you use rpm, apt-get, or some other tool to upgrade to the latest version, you discover that you've lost your changes because the replacement package included a new default configuration file that overwrote the original. Fortunately, both RPM and the Debian package system can mark configuration files as such. When the system installs a package, it backs up your existing configuration files by renaming them with a new extension, such as .rpmsave. Nonetheless, the need to go in and swap in your own working configuration file can be annoying. If a package is built incorrectly, it may lack the configuration file flag, causing your originals to be lost.

Some tools change the original configuration files, or other aspects of a system's configuration, when you run them—even if you don't ask for these changes to occur. For instance, Mandrake includes a package called Mandrake Security (msec), which periodically checks assorted directories for preconfigured levels of security. If the tool finds a problem, such as too-permissive permissions on a directory, the tool corrects the problem. This practice is a good one overall, but if you, as an informed and intelligent system administrator, don't want this tool changing your directory permissions without warning or even notification, you must dig into the tool's configuration and change it. Other tools might run even when you don't ask them to do so, or they might make changes beyond those you'd expect. For instance, it's becoming increasingly common for programs to try to add themselves to KDE, GNOME, and other environments' menus after they're installed. This practice might be fine if the tools do their jobs correctly, but sometimes they might delete entries for programs you've added manually, or they might create multiple entries for themselves if they run multiple times. Such problems can be difficult to track down, because it might not be obvious which program made the unauthorized changes. In the end, the best defense is to make backups of all your configuration files—both system files in

/etc and user configuration files, which are generally dot-files in users' home directories.

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