Problem
If you setup a system, you want to make sure that it complies to a pre-defined config. You can do that with some configuration management system, but there are cases where it useful to do that outside of this context.
Solution
The shell script below I started to write in 2008. Over time (until 2016) it extended into something which is able to output a report of over 1000 items. You can configure it via ${HOME}/.check_host.cfg and /etc/check_host.cfg (it reads both in this order, first config wins and other config is not read). You can use option “-h” to see the usage text. Option “-n” suppresses messages which help to fix issues, “-a” prints out simple HTML instead of text.