Final Update: Wednesday, 24 February 2021 00:59 UTC
We've confirmed that all systems are back to normal with no customer impact as of 2/24, 00:20 UTC. Our logs show the incident started on 2/23, 19:45 UTC and that during the ~4 hours 25 min that it took to resolve the issue customers in East US2 experienced intermittent data latency and incorrect alert activation.
Root Cause: The failure was due to one of the backend services becoming unhealthy.
Incident Timeline: 4 Hours & 25 minutes - 2/23, 19:45 UTC through 2/24, 00:20 UTC
We understand that customers rely on Azure Log Analytics as a critical service and apologize for any impact this incident caused.