Final Update: Wednesday, 09 January 2019 18:47 UTC
We've confirmed that all systems are back to normal with no customer impact as of 1/9, 18:20 UTC. Our logs show the incident started on 1/9, 14:50 UTC and that during the time it took to resolve the issue customers who would have normally received a web test failure alert may have not received the expected alert.
Root Cause: The failure was due to a certificate chain validation problem on a number of hosts.
Incident Timeline: 3 Hours & 30 minutes - 1/9, 14:50 UTC through 1/9, 18:20 UTC
We understand that customers rely on Application Insights as a critical service and apologize for any impact this incident caused.
Initial Update: Wednesday, 09 January 2019 17:30 UTC
We are aware of issues within Application Insights and are actively investigating. Some customers may experience Alerting failure.
Work Around: None
Next Update: Before 01/09 19:30 UTC
We are working hard to resolve this issue and apologize for any inconvenience.