On September 17, 2024, Cloudflare experienced an outage affecting some Business plan websites for approximately one hour due to an internal software error. The issue occurred during routine maintenance when IPv4 prefixes were inadvertently stopped from being announced, causing traffic not to reach the affected websites. This was a result of a batch of websites that remained linked to old addresses after renumbering work in July 2024. Cloudflare has since fixed the specific bug and is implementing measures to prevent similar issues in the future, including adding tests for outstanding website assignments, improving processes associated with prefix withdrawal, and reviewing every use of stored procedures and functions related to legacy systems.