Introduction

This document serves as a Root Cause Analysis for the service interruption experienced by Ex Libris customers.
The goal of this document is to share our findings regarding the event, specify the root cause analysis, outline actions to be taken to solve the downtime event, as well as preventive measures Ex Libris is taking to avoid similar cases in future.

Event Timeline

Service degradation was experienced by Ex Libris customers served by the Higher-Ed Platform EU03 instance at the Munich Data Center between:

December 3, 2025, from 11:00-11:11 AM Munich time.

During the event, the system was unavailable.

Root Cause Analysis

Ex Libris Engineers investigated this event to determine the root cause analysis with the following results:

For high availability, each search engine consists of two nodes—a leader and a replica.

During the incident, the replica suffered degraded performance because of a problem with its physical host.

Although the replica never went completely offline, its impaired state affected the leader, causing intermittent service across the entire instance.

Once our engineers shut down the replica, the leader was able to recover and restore normal operation.

Technical Action Items and Preventive Measures

Ex Libris has taken the following action and preventive measures to avoid such an occurrence in future:

• Our engineers migrated the replica to another physical host and restored the high availability for the instance.

Customer Communication

ExLibris is committed to providing customers with prompt and ongoing updates during Cloud events. Ongoing and prompt updates on service interruptions appear in the system status portal at this address: http://status.exlibrisgroup.com/

These updates are automatically sent as emails to registered customers.