This document serves as a Root Cause Analysis for the Alma service interruption experienced by Ex Libris customers on April 21, 2021.
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.
Service interruption was experienced by Ex Libris customers served by the Alma NA04 instance during the following hours:
April 21, 2021 from 04:40 AM until 05:28 AM PST: During the event, the service was unavailable.
Root Cause Analysis
Ex Libris engineers investigated this event to determine the root cause of this issue and concluded the following:
A bug in the Database process that gathers statistics caused corruption in some indexes that resulted in an unresponsive Database.
Ex Libris engineers fixed the corrupted indexes and are working with the DB provider to deploy a fix.
Technical Action Items and Preventive Measures
Ex Libris has taken the following action and preventive measures to avoid such an occurrence in future:
- We are working with the DB provider support to deploy a permanent fix
- Added a New monitoring to identify the issue if reoccurs
- Created a new procedure to fix such issue if reoccurs
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.