System-wide configuration files are usually found in /etc. Personalized configuration files are stored in the user's home directory, in files and subdirectories preceded by a "." in their name.
NIS
text file
NIS package
Unix / Linux are both file based operating systems. The majority of configuration can be amended by system configuration files, although as the systems have developed more and more of this is automated and hidden from the user. User configuration files will normally reside under the /etc directory.
NIS (Network Information Service).
According to the Linux+ Guide to Linux Certification 2nd ed., most configuration files on Linux systems are delimited using the colon symbol (:) while the awk command uses spaces or tabs as delimiters for each field in a line. SudoKing, please note that the hash symbol (#) allows the commenting of lines, not the delimiting of lines. This is not to be confused with a hashpling (such as #!/bin/bash) which is located on the first line in a shell script, and specifies the pathname to the shell that interprets the contents of the shell script.
Look at these files: /etc/hosts /etc/NetworkManager/NetworkManager.conf /etc/ncsd.conf
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One common problem that is faced by Linux system administrators is not understanding permissions. Not backing up critical configuration files and not choosing good root passwords are other problems new Linux system administrators may face.
You don't mention what you are looking for in terms of a "running configuration file". In Unix/Linux there are many of these. Most of them can be found in the /etc directory or its subdirectories but not all of them are located in /etc.
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/dev