Postmortems, reliability notes, and operational lessons from engineering teams.
We have completed a massive engineering effort to make our infrastructure more resilient. Through new tools like Snapstone and the Engineering Codex, we've implemented safer configuration changes and automated best practices to prevent future incidents.
Cloudflare suffered a service outage on February 20, 2026. A subset of customers who use Cloudflare’s Bring Your Own IP (BYOIP) service saw their routes to the Internet withdrawn via Border Gateway Protocol (BGP).
An automated routing policy configuration error caused us to leak some Border Gateway Protocol prefixes unintentionally from a router at our Miami data center. We discuss the impact and the changes we are implementing as a result.
A recent change to 1.1.1.1 accidentally altered the order of CNAME records in DNS responses, breaking resolution for some clients. This post explores the technical root cause, examines the source code of affected resolvers, and dives into the inherent ambiguities of the DNS RFCs.
We have declared “Code Orange: Fail Small” to focus everyone at Cloudflare on a set of high-priority workstreams with one simple goal: ensure that the cause of our last two global outages never happens again.
Cloudflare experienced a significant traffic outage on December 5, 2025, starting approximately at 8:47 UTC. The incident lasted approximately 25 minutes before resolution. We are sorry for the impact that it caused to our customers and the Internet. The incident was not caused by an attack and was due to configuration changes being applied to attempt to mitigate a recent industry-wide vulnerability impacting React...
Cloudflare suffered a service outage on November 18, 2025. The outage was triggered by a bug in generation logic for a Bot Management feature file causing many Cloudflare services to be affected.
Cloudflare’s Dashboard and a set of related APIs were unavailable or partially available for an hour starting on Sep 12, 17:57 UTC. The outage did not affect the serving of cached files via the
An advanced threat actor, GRUB1, exploited the integration between Salesloft’s Drift chat agent and Salesforce to gain unauthorized access to Salesforce tenants of Cloudflare and many other companies.
On August 21, 2025, an influx of traffic directed toward clients hosted in AWS us-east-1 caused severe congestion on links between Cloudflare and us-east-1. In this post, we explain the details.
Workers KV is Cloudflare's global key-value store. After the incident on June 12, we re-architected KV’s redundant storage backend, remove single points of failure, and make substantial improvements.
Multiple Cloudflare services, including Workers KV, Access, WARP and the Cloudflare dashboard, experienced an outage for up to 2 hours and 28 minutes on June 12, 2025.