Final Update: Saturday, 19 September 2020 01:13 UTC
We've confirmed that all systems are back to normal with no customer impact for our USGov Virginia, USGov Texas, USGov Arizona, DoDCentral, and DoDEast regions of the US Gov cloud as of 9/18, 20:00 EDT. Our logs show the incident started on 5/18, 13:00 EDT and that during the 7 hours that it took to resolve the issue customers using Diagnostic Settings to export logs and metrics to Log Analytics would have experienced data loss/gaps in their Log Analytics workspaces during this time. Due to this customers may have also experienced false and missed alerts.
Root Cause: The failure was due to an authentication issue that took down our data export to Log Analytics.