We've confirmed that all systems are back to normal with no customer impact as of 12/10, 09:35 UTC. Our logs show the incident started on 12/10, 09:10 UTC and that during the 25 minutes that it took to resolve the issue some customers in Australia South East region may have experienced data access issue in the azure portal and query failure.
Root Cause: The failure was due to an issue with one of our backend service.
Incident Timeline: 25 minutes - 12/10, 09:10 UTC through 12/10, 09:35 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.