We've confirmed that all systems are back to normal with no customer impact as of 06/27, 10:06 UTC. Our logs show the incident started on 06/27, 09:48 UTC and that during the 18 minutes that it took to resolve the issue some of the customers in Central US region may have experienced issues accessing their data as well as missed or delayed alerts.
Root Cause: The failure was due to backend dependency service becoming unhealthy.
Incident Timeline: 18 minutes - 06/27, 09:48 UTC through 06/27, 10:06 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.