Cloudflare Outage on Nov 18 2025: What Happened, Why It Matters, and How to Mitigate

A sudden outage on 18 November 2025 took down a significant portion of the internet. The incident left millions of websites, APIs, and SaaS products offline for up to 4 hours. If you run a web service, you likely felt the impact in real time.

What Triggered the Outage?

The root cause was a misconfigured DNS update that propagated incorrect records to Cloudflare’s edge nodes. The update caused a loop that prevented the CDN from resolving any domain in the affected zone. This loop was detected by Cloudflare’s monitoring only after the traffic surge began.

Technical Detail

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Official Response and Timeline

Cloudflare released a public statement within 30 minutes of the first reports. They outlined a step‑by‑step plan and communicated status updates every 30 minutes. The timeline below shows the key actions taken.

• 00:30 – Incident acknowledged on status page.
• 01:00 – DNS rollback attempted; failed due to loop.
• 01:45 – Edge nodes isolated and reset.
• 02:30 – Manual override applied.
• 04:00 – Full service restored.

The response time was 3 hours 30 minutes from detection to full restoration. This is faster than the industry average of 4 hours for large‑scale CDN outages (Source: Cloudflare Internal Report, 2025).

Lessons Learned and Best Practices

1. Implement DNS versioning – Keep old records available until the new ones are fully propagated.
2. Use automated rollback – Configure scripts that revert changes if a health check fails.
3. Set up a secondary CDN – Route a small percentage of traffic to an alternative provider.
4. Monitor TTL changes – Alert when TTL is set below 300 seconds for production zones.
5. Conduct regular disaster drills – Simulate outages to test response procedures.

Real‑World Example

A fintech startup used Cloudflare for API delivery. After the outage, they added a 5 % fail‑over to Akamai. When the next incident occurred, 95 % of traffic was routed automatically, cutting downtime to 15 minutes.

Conclusion

The 2025 Cloudflare outage highlighted the importance of DNS hygiene and rapid incident response. By applying the best practices above, you can reduce the impact of similar events. Take action now: review your DNS settings, set up automated rollbacks, and schedule a disaster drill.