Fast DNS resolvers are a crucial component in delivering a snappy internet experience for end-customers. If the resolvers are down or under heavy load, even the best internet connection is useless for most customers. In this talk I'll cover how to design and set up a scalable, highly available DNS resolver infrastructure for internet service providers. - Anycast IPs using BGP for horizontal scaling and high-availability - Health checks - Scaling nodes vertically to optimize cache ratios - Automation is key None about this event: https://pretalx.com/denog13/talk/PLT8NF/