https://rudd-o.com/linux-and-free-software/using-varnish-to-fully-capitalize-on-image-hotlinking
Using Varnish to capitalize on image hotlinkers and retain referred visitors — Rudd-O.com
Hotlinkers suck your bandwidth dry, but referrals are valuable to you. Learn how to use Varnish to stop image hotlinkers while at the same time welcoming...
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