On Sun, 29 October 2000, smd@clock.org wrote:
P.S.: any chance you can be a bit more concrete about what's happening?
When I'm concrete, providers complain I'm picking on them, and getting them bad press. But since you asked.... At approximately 7:37am EDT on Friday, about 258 Cisco 12000's on UUNET's primary backbone reloaded. This appeared to be isolated to routers in ASN 701. It disrupted reachability to about 15% of the world-wide Internet based on data from Matrix measurements. A contributing cause was a bad IS-IS packet which confused certain IOS versions in the 12.0 IOS software train. I haven't heard what the root cause was or what originated the bad IS-IS packet. The Cisco bug id is CSCdr05779. Any provider running the affected IOS version may be vulnerable depending on what the root cause turns out to be. Although the bad IS-IS packet didn't propagate to other providers, several other providers did report BGP resets and route flaps about the same time.