We've confirmed that all systems are back to normal with no customer impact as of 12/7, 00:32 UTC. Our logs show the incident started on 12/6, 23:46 UTC and that during the 46 minutes that it took to resolve the issue customers may have experienced data access issues as well as failed or misfired alerts for Azure Log Analytics in North Europe.
Root Cause: The failure was due to an upgrade of one of our back end systems.
Incident Timeline: 46 minutes - 12/6, 23:46 UTC through 12/7, 00:32 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.
Update: Monday, 07 December 2020 00:17 UTC
We continue to investigate issues within Log Analytics. Root cause is not fully understood at this time. Some customers may experience experience data access issues as well as failed or misfired alerts for Azure Log Analytics in North Europe. We are working to establish the start time for the issue, initial findings indicate that the problem began at 12/06 23:46 UTC. We currently have no estimate for resolution.