Cloudflare: firmware reboot time investigation using UEFI debugging

Category: Engineering post
Status: confirmed
Sources: Cloudflare Blog
Summary: Cloudflare published a post on 2026-06-01 investigating why firmware updates caused core servers to take four hours to reboot. The investigation involved diving into UEFI data structures and iPXE automation. Eliminating unnecessary timeouts cut boot times back to minutes.
Why it matters: Demonstrates systematic bare-metal debugging combining UEFI internals analysis and boot automation, applicable to any team operating physical server fleets.