We've confirmed that all systems are back to normal with no customer impact as of 03/03, 06:15 PM UTC. Our logs show the incident started on 03/02, 06:15 AM UTC and that during the 12 hours that it took to resolve the issue 10 customers experienced issues while ingesting and viewing a particular data type: Syslog (LINUX_SYS_LOGS_TABLE) in Log Analytics.
Root Cause: The failure was due to a recent change in one of our dependent services.
Incident Timeline: 12 Hours - 03/02, 06:15 AM UTC through 03/03, 06:15 AM UTC
We understand that customers rely on Azure Log Analytics Service as a critical service and apologize for any impact this incident caused.
Update: Saturday, 03 March 2018 04:41 UTC
We continue to investigate issues within Log Analytics. Root cause is not fully understood at this time. Some customers may face issues while ingesting a particular data type: Syslog (LINUX_SYS_LOGS_TABLE) to Log Analytics. We are working to establish the start time for the issue, initial findings indicate that the problem began at 03/02 ~06:15 AM UTC. We currently have no estimate for resolution.