Introduction

This document serves as a Root Cause Analysis for the Primo service interruption experienced by Ex Libris customers on October 5, 2015.

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 Primo TC EU00 instance at the Europe Data Center during the following hours: 

October 5, 2015 from 11:04 AM until 11:40 AM Central European Time.

During the event the environment was very slow and became unavailable.

Root Cause Analysis

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

An unexpected load on Search engines and on the Front Ends had taken place. The extensive load on the system elements had caused the slowness and in the extreme cases it had caused the system to build a high queue that prevented it from operating at all.

Technical Action Items and Preventive Measures

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

• To accommodate the load, the environment had been updated with the following :
  o Additional computing unit (CPU) were added to the Search Engines
  o A code correction was added to the environment to allow better performance of the front ends.
• Monitoring had been set to have a more sensitive thresholds to allow identification of possible slowness earlier

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/