Some parts of the content come from https://hostedtalk.net/t/connecting-uptime-robot-with-ns1-dns-api/3883 。 Goal I have quite a few VPSes around the world, but my website had been served by a single VPS in Los Angeles for a long time. Because I purchase VPSes from small providers for their specific routing configuration or low price, the network of this VPS can be unstable from time to time. Although it's rare, I had to manually point the DNS to another VPS in case of an outage and switch back after it's back up. Therefore, I want to serve my website with all my VPSes, and automatically reroute traffic to other VPSes if one VPS is down. Synchronizing website data is of no difficulty since I use Hexo, a static site generator....

Previously, if you wanted to build your own authoritative DNS system for a website, the (almost) only option was PowerDNS with its GeoIP backend. However, the GeoIP backend uses YAML configuration files and cannot work with databases like MySQL. This meant having to manually set up a cross-server file synchronization system instead of using more mature database synchronization technologies. Fortunately, PowerDNS added support for Lua records in its latest 4.2 version. Lua is a programming language specifically designed for "embedding functionality into other programs," which you may have encountered in nginx (as a plugin). Lua record support enables PowerDNS to return different responses based on user query requests, thus implementing GeoDNS functionality for regional resolution....