We've confirmed that all systems are back to normal with no customer impact as of 8/16, 19:30 UTC. Our logs show the incident started on 8/16, 16:56 UTC and that during the 2 hours and 34 minutes that it took to resolve the issue small set of customers in West Central US Region experienced issues with data access in Log Analytics and also issues with delayed or missed Log Search Alerts.
Root Cause: The failure was due to issues with one of the dependent services.
Incident Timeline: 2 Hours & 34 minutes - 8/16, 16:56 UTC through 8/16, 19:30 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.