We've confirmed that all systems are back to normal with no customer impact as of 03/28, 13:15 UTC. Our logs show the incident started on 03/28, 10:15 UTC and that during the 3 hours that it took to resolve the issue a small subset of customers would have seen incorrect alert states on the Azure Portal and received delayed notifications. This issue only impacted classic alerts.
Root Cause: The failure was due to a failure in one of our downstream services.
Incident Timeline: 3 Hours - 03/28, , 10:15 UTC through 03/28, 13:15 UTC
We understand that customers rely on Application Insights as a critical service and apologize for any impact this incident caused.
Initial Update: Thursday, 28 March 2019 12:10 UTC
We are aware of issues within Application Insights and are actively investigating. Some customers may see incorrect alert states. This impacts only classic alerts.
Work Around: None
Next Update: Before 03/28 16:30 UTC
We are working hard to resolve this issue and apologize for any inconvenience. -Varun