EU04 - RCA - July 14, 2022
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 interruption was experienced by Ex Libris customers served by the Higher-Ed Platform EU04 instance at the Frankfurt Data Center between July 14, 2022, from 13:20 until 13:36 Frankfurt time.
During this time frame the service was either slow or unresponsive for the effected products. Primo VE was only mildly affected.
Root Cause Analysis
Ex Libris Engineers investigated this event to determine the root cause analysis with the following results:
High memory utilization on two search engine nodes caused slowness to gradually develop and eventually the system became unresponsive. The memory stress developed without early warning.
Once the issue was identified by our monitoring systems our engineers restarted both nodes to restore stable service.
This event is a repeat of the EU04 event which occurred on June 30, 2022 in which memory was added.
The added memory did not solve the root cause and only managed to shorten the event. Further analysis showed that a bug in the application eventually caused both events which was fixed accordingly on July 18th.
Technical Action Items and Preventive Measures
Ex Libris has taken the following action and preventive measures to avoid such an occurrence in future:
- The bug was fixed and injected to EU04 on July 18, 2022,
- We are monitoring the environment closely to ensure this fix is working as expected.
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.