Update: Dyn says services were restored at 9:36 A.M. Eastern time, and I can now connect to the affected websites again—which indicates the two events were indeed related.
Update 2: Dyn says it was hit with another DDoS attack at 11:52 A.M. Eastern. Currently, Twitter, Etsy, Spotify and the other sites affected by the earlier attack are offline from my location in the Northeast U.S.
Every morning, I sit down at my PC with a cup of coffee, crank some tunes on Spotify, and scour r/techsupportgore for gnarly PC disaster pics to tweet out. Not this morning, because it appears a massive Distributed Denial of Service attack targeting DNS host Dyn has knocked a big chunk of the Internet offline Friday morning.
The Domain Name System (DNS) converts human-readable URLs (like "pcworld.com") to their underlying numeric IP addresses. Dyn hasn't confirmed that the outages and its DDoS attack are related, but it seems likely.
Hacker News users report the following sites are down:
Trying to connect to all of those sites indeed proved fruitless this morning. Zoho, SaneBox, and iHeart Radio also appear to be down on my end, in New Hampshire. Your mileage may vary, however, as Dyn says the connectivity issues are largely limited to the east coast. A DownDetector.com check of backbone Internet provider Level3 helps reveal the extent of the problem, as first reported by Gizmodo.
Two hours ago, Dyn posted the following status report:
“Starting at 11:10 UTC on October 21th-Friday 2016 we began monitoring and mitigating a DDoS attack against our Dyn Managed DNS infrastructure. Some customers may experience increased DNS query latency and delayed zone propagation during this time.”
The company says its engineers are toiling to fix the issues. If the sound of silence is troubling you in the meantime, Twitch and YouTube are still working just fine.