Introduction

This document serves as a Root Cause Analysis for the Primo 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 Primo MT EU03 instance at the European Data Center during the following hours: 

May 24, 2017 from 3:54 PM until 4:27 PM Amsterdam 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:

There was a massive misuse of the multiple recipient mail functionality in Primo.
As a result some ISPs put Ex Libris in blacklist and mails were blocked.
This caused high load in the mail relay queue which resulted in problems of disk space and DB connections.

Technical Action Items and Preventive Measures

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

• Application restart solved the specific problem
• The IPs that misused the mail functionality were blocked
• A fix regarding mail functionality in Primo was implemented immediately

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.

Publication History