We've confirmed that all systems are back to normal with no customer impact as of 01/10, 14:35 UTC. Our logs show the incident started on 01/10, 10:45 UTC and that during the 3 hours 50 minutes that it took to resolve the issue some customers with Application Insights components in Brazil South geographical region during impacted window may have experienced intermittent metric data gaps and incorrect metric alert activation..
Root Cause: The failure was due to issue with one of instance in unhealthy state.
Incident Timeline: 3 Hours & 50 minutes - 01/10, 10:45 UTC through 01/10, 14:35 UTC
We understand that customers rely on Application Insights as a critical service and apologize for any impact this incident caused.