Your IPs, your rules: enabling more efficient address space usage

Cloudflare describes enhancements to BYOIP management that let customers dynamically split and rebind IP prefixes across CDN, Spectrum, and Magic Transit to improve utilization amid IPv4 scarcity and rising costs. The post details how Linux iptables/IP sets and an extended eBPF-based Tubular bind IPs and ports to services on the fly, integrating with the current NGINX ingress via a shared Unix socket and rolling out changes safely across the global fleet. It also previews reducing the current 4–6 hour routing uncertainty during migrations to minutes and enabling granular, programmable service bindings down to subranges and ports via API.