We've confirmed that all systems are back to normal with no further customer impact as of 10/21, 20:11 UTC. Our logs show the incident started on 10/21, 20:03 UTC and that during the 8 minutes that it took to resolve the issue 9.2% of customers experienced difficulties accessing data in the West US 2 region.
Root Cause: The failure was due to a back end data system.
Incident Timeline: 8 minutes - 10/21, 20:03 UTC through 10/21, 20:11 UTC
We understand that customers rely on Application Insights as a critical service and apologize for any impact this incident caused.