Final Update: Wednesday, 15 December 2021 04:24 UTC
We've confirmed that all systems are back to normal as of 12/15, 02:43 UTC. Our logs show the incident started on 12/15, 00:14 UTC and during the time it took to resolve the issue Azure Log Analytics and / or Azure Sentinel customers experienced data ingestion delays and missed log search alerts. Additionally during this time, customer may have encountered failures with Control Plan CRUD operations.
Root Cause: The failure was due to service performance degradation.
Incident Timeline: 2 Hours & 29 minutes - 12/15, 00:14 UTC through 12/15, 02:43 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.