We've confirmed that all systems are back to normal with no customer impact as of 07/08, 15:55 UTC. Our logs show the incident started on 07/08, 11:55 UTC and that during the 4 hours that it took to resolve the issue 15% of customers using Log Analytics would have experienced data access issues in East US region including issues accessing Log Search Alerts and Log Search queries via the Azure Portal..
Root Cause: The failure was due to issues with one of our backend services which went in to unhealthy state.
Incident Timeline: 4 Hours - 07/08, 11:55 UTC through 07/08, 15:55 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.
Update: Monday, 08 July 2019 15:38 UTC
We continue to investigate issues within Log Analytics. Root cause is not fully understood at this time. Some customers using Log Analytics in East US may experience data access issues including issues accessing Log Search Alerts and Log Search queries via the Azure Portal.. We are working to establish the start time for the issue, initial findings indicate that the problem began at 07/08 ~11:55 UTC. We currently have no estimate for resolution.
Work Around: None
Next Update: Before 07/08 18:00 UTC
Initial Update: Monday, 08 July 2019 13:21 UTC
We are aware of issues within Log Analytics and are actively investigating. Some customers may experience data access issue in east US region as our dependent backend service is having issues. Some customers may also see query degradation and face issues with log search alerts.
Work Around: none
Next Update: Before 07/08 15:30 UTC
We are working hard to resolve this issue and apologize for any inconvenience. -Rama