Why Your Lab Domain Suddenly Stopped Resolving (DNS Blocklists)

You wake up, grab coffee, and nothing works. Grafana won't load. Your reverse proxy is throwing 502s. SSH to your machines by hostname? Nope. But pinging by IP? Works fine. Congratulations, your domain just got added to a DNS blocklist and your entire homelab infrastructure fell over like dominoes. I hit this exact scenario a few months ago with a domain I'd been using for my lab for over a year. Everything was fine until it wasn't. Let me walk you through what happened, why it happens, and how