# How Bad Can a Bug Get? An Empirical Analysis of Software Failures in the OpenStack Cloud Computing Platform

## TL;DR

This paper empirically investigates the severity and propagation of software failures in OpenStack, revealing many failures go undetected and can silently spread, highlighting the need for improved runtime checks.

## Contribution

It provides an empirical analysis of failure impacts in OpenStack, emphasizing failure detection issues and propagation, and suggests improvements for fault containment.

## Key findings

- Most failures are not detected promptly
- Failures can silently propagate across components
- Run-time checks need enhancement

## Abstract

Cloud management systems provide abstractions and APIs for programmatically configuring cloud infrastructures. Unfortunately, residual software bugs in these systems can potentially lead to high-severity failures, such as prolonged outages and data losses. In this paper, we investigate the impact of failures in the context widespread OpenStack cloud management system, by performing fault injection and by analyzing the impact of the resulting failures in terms of fail-stop behavior, failure detection through logging, and failure propagation across components. The analysis points out that most of the failures are not timely detected and notified; moreover, many of these failures can silently propagate over time and through components of the cloud management system, which call for more thorough run-time checks and fault containment.