[jrochkind1]

It's a good idea to always look up the docs on directives in apache configs you are copy-pasting from the internet, to make sure you know what they are doing.

For that matter, this probably applies to just about anything you copy paste on the internet. Understand what you're pasting, look up the docs if you don't or aren't sure or are using something you haven't seen before.

But apache httpd configs can be especially tricky. The accidental open proxy is definitely something that gets lots of people, you are not alone. The apache httpd directive names have a lot of 'legacy' in them, and probably should have been named more clearly in retrospect (i assume the apache httpd forward proxy feature came first, and reverse proxy was only added later; but in 2015 reverse proxy is a lot ore common a thing to want).

(But the solution to an accidental open proxy, if you didn't mean to be forward proxying at all.... is turning off the forward proxy in apache httpd, not other weird workarounds).