Why was the portal broken on August 29th?

Below is a synopsis of interruption to production campus portal service on Tuesday, August 29. The interruption began approximately 10:16am and was restored approximately 10:35am.
Automatic directory replication resulted in a source library version update being automatically deployed from a staging node to a production application node outside of a scheduled maintenance window. This version created a conflict condition with other DLL versions on the receiving node, creating a service interruption.
Service was restored by resolving versioning conflicts on the receiving node. Long term remediation will be accomplished by disabling automatic directory replication across nodes, isolating the staging environment outside of scheduled maintenance windows.