When: 01:08 - 01:34 PDT September 12 (08:08 - 08:34 GMT; 17:08 - 17:34 KST) Impact: Full outage - all services unavailable Root cause: Ongoing investigation with AWS regarding high engine CPU utilization and ElastiCache replication lag that caused auto-scaling policies to take effect. Remediation: Terminated instances, and scaled in auto-scaled resources.