This chapter is only intended as an introduction to the files in the /etc/sysconfig/ directory. The following source contains more comprehensive information.
/usr/share/doc/initscripts-<version-number>/sysconfig.txt — This file contains a more authoritative listing of the files found in the /etc/sysconfig/ directory and the configuration options available for them. The <version-number> in the path to this file corresponds to the version of the initscripts package installed.