All you need to know can be found
here. That being said, you can find basics for status checkers around written in
perl,
php,
bash or even
assembler out of all languages
Just grab w/e suits you best (or write something own basing on cvet's post), display it, done.
If you're familiar with php, take a look how fodev-status displays servers summary [
code,
result] and adjust to your needs.
Long, long time ago there was a single-php-file where you could simply define server address/port via url, so it worked with any server you wanted and was easiest to setup. Originally written by
jan0s1k, maybe it's still around saved by someone, somewhere~