Introduction

This document serves as a Root Cause Analysis for the Alma service interruption experienced by Ex Libris customers on April 16th, 2018.

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 Alma AP01 instance at the APAC Data Center during the following hours:

April 16th, 2018 from 10:14 AM until 12:38 PM Singapore time

During the event, the service was unavailable for the environment.

Root Cause Analysis

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

A defect in a frequently used SQL query, caused a severe load on the DB server which lead to a general unavailability of the entire system

Technical Action Items and Preventive Measures

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

• During the event Ex Libris engineers tried to locate where the application call to DB is coming from.
• Once the problematic SQL was identified DB statistics were re-created to restore normal system behavior.
• An application fix that will address this from the root is being applied at the beginning of this week.

Customer Communication 

April 25th session

May 7th session

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.

Publication History