LAST UPDATE: September 2017
Due to issues with similar plugins, we decided to create our own spider/crawler blocker plugin, called Spider Blocker. It’s completely free, open-source and without footprints. You can easily add it to each new blog in the Easy Blog Networks Add Blog form or download it from WordPress.org and install it.
Setup Spider Blocker
Plugin will block the most common crawlers like Majestic, Ahrefs and MOZ and hide your blogs from prying eyes of your competitors. It will do so by editing .htaccess file. It has no footprints and responds with standard 404 error when pinged.
Once installed Spider Blocker can be found under Tools menu. You can easily add new, remove existing or just allow/disallow existing spiders.
Some users receive “fatal error” when activating the plugin. This is most commonly caused by outdated PHP. Make sure your server is running PHP 5.4+ and Apache 2.4+.