Introduction

This document serves as a Root Cause Analysis for the Alma service interruption experienced by Ex Libris customers on April 2, 2025.
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 interruption was experienced by Ex Libris customers served by the HEP NA01, NA02, NA03, NA91  instances during the following hours: 

April 2, 2025, from 2:45 PM until 3:35 PM Chicago time.

During the event, the service was intermittent.

Root Cause Analysis

Ex Libris engineers investigated this event to determine the root cause of this issue and concluded the following:

High CPU usage on the Web Application Firewall (WAF) caused slowness and disruptions to the services in the Data Center.

The WAF was disabled by the Network team, resulting in immediate restoration of normal operations.

Technical Action Items and Preventive Measures

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

The network team reviewed and optimized the WAF policies to ensure efficient CPU usage and improved performance.

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.