This document serves as a Root Cause Analysis for the Higher-Ed Platform service interruption experienced by Ex Libris customers on August 12, 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.
Higher-Ed Platform NA06
Service interruption was experienced by Ex Libris customers served by the Higher-Ed Platform NA06 instance at the Seattle Data Center between August 12, 2021 from 01:06 until 01:34 Seattle time.
During the event, Service was unavailable for the environment
Root Cause Analysis
Ex Libris engineers investigated this event to determine the root cause of this issue and concluded the following:
The service disruption was due to a DB failure as a result of a connection pileup during the one-by-one restart of the nodes followed the code injection, the code injection is a standard practice for the Higher-Ed Platform, which is always executed during nighttime and designed to be a non-disruptive, we determined that the underlying reason is in the cache startup code.
Technical Action Items and Preventive Measures
Ex Libris has taken the following action and preventive measures to avoid such an occurrence in future:
Once the DB failure was detected the DB was restarted to restore normal service
We are currently examining the cache startup code to determine why it had the adverse effect on the DB connection pool which was not experience before, once this is determined the code will be fixed
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.