Security advisories

Summary

On October 21st, 2016, Dyn, a major managed DNS provider, experienced a Distributed Denial of Service attack, which led to outages affecting several major websites, including Fastly infrastructure (such as the Fastly Control Panel and API) and Fastly customers.

Fastly worked with our additional managed DNS providers to ensure availability during the incident. This mitigated impact on Fastly customers.

Fastly is working with customers to help them adjust DNS configurations to increase DNS resiliency. Customers that continue to see impact are advised to contact Fastly Customer Engineering for further assistance.

Impact

During the initial attack on Dyn, users of Fastly customers may have seen performance degradations or DNS resolution errors while visiting websites on the Fastly CDN, or Fastly infrastructure.

Detail

A Distributed Denial of Service attack on the Dyn managed DNS infrastructure led to several name servers authoritative for fastly.net, as well as several customer domains, becoming unresponsive.

Fix / workarounds

Fastly worked with our additional managed DNS providers to increase resilience and ensure availability during the incident to reduce impact on Fastly customers. However, due to the nature of DNS and DNS caching, it is possible that customers experienced outages while the modification propagated.

Fastly is working with customers to help them adjust DNS configurations. Customers that continue to see impact are advised to contact Fastly Customer Engineering for further assistance. Customers who use Dyn as their authoritative DNS provider should work with their provider to mitigate continued issues related to the availability of their domain.

More information

Updates on the incident affecting Dyn can be found on the Dyn status page at https://www.dynstatus.com/.