We've confirmed that all systems are back to normal with no customer impact as of 06/11, 08:33 UTC. Our logs show the incident started on 06/11, 06:53 UTC and that during the 1 hour 40 minutes that it took to resolve the issue some of customers may have experienced data access issue and missed delayed alerts in West Central US region.
Root Cause: The failure was due to one of our back end services.
Incident Timeline: 1 Hours & 40 minutes - 06/11, 06:53 UTC through 06/11, 08:33 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused. -Syed