IT outages can have far-reaching repercussions, disrupting services and affecting millions of people. We are all so used to being connected to various networks that we take it for granted that systems are robust and almost infallible. So when global system "crashes" occur, panic and despair spread like wildfire.

On more than one occasion, the world has witnessed such collapses, which have caused widespread chaos, at many levels, and triggered collective nervous breakdowns. The lessons behind the panic? The critical importance of robust and reliable systems and the need for effective contingency plans.

Recently, a widespread IT outage caused disruption in several sectors in Australia, affecting major airlines, media and banks. The incident caused grounded flights, chaos in supermarkets and failures in the broadcasting network. At Sydney airport, departure boards went blank. Retail operations and banking services were also severely affected: supermarkets suffered checkout chaos and major banks, including National Australia Bank, suffered major service disruptions. The media sector was not spared either. The cause of the outage remains unclear, but there is speculation that it is related to Microsoft's operating systems for personal computers.

Computer failures can be caused by many factors. Simple errors such as typos in code, faulty hardware and power outages are common culprits in disrupting services. Cyber-attacks add another layer of vulnerability, where malicious actors exploit weaknesses to cause widespread disruptions. Environmental factors also play an important role: adverse weather conditions such as heat waves, storms and natural disasters can damage data centres, large facilities that house servers essential for online services.

The shift from in-house server management to cloud-based infrastructure has further complicated the picture. While cloud services have enabled companies to innovate and scale quickly, they also create single points of failure. An outage at a major cloud provider such as Amazon Web Services (AWS), Microsoft Azure or Google Cloud can affect thousands of customers simultaneously. Sudden spikes in demand, such as during peak events or periods of staff reductions, can exacerbate these problems and lead to prolonged or more complex outages.
Read also: Article: Want to improve the cyber resilience of your workforce? Here are 8 strategies (peoplemattersglobal.com)
Below, we explore five of the most significant IT outages that have left a lasting impact on the world of technology.

1. CrowdStrike Crash: Faulty Software Update

On 19 July 2024, cybersecurity giant CrowdStrike faced an unprecedented crisis when a faulty software update caused a widespread outage. The update caused Microsoft's operating system to crash, resulting in a worldwide outage that affected approximately 8.5 million devices with the infamous blue screen of death (BSOD). Major services such as airports, hospitals, public transport, financial services and media were paralysed. The incident cost Fortune 500 companies an estimated $5.4 billion, making it the most expensive computer outage in history. CrowdStrike's rapid response was crucial in mitigating further damage, highlighting the need for diverse software solutions to prevent such global disruptions.

2. Amazon Web Services Outage: A Human Typo

In 2017, the tech industry was rocked by a major outage at Amazon Web Services (AWS), the leading cloud computing provider. The cause? A simple human error during a debugging session. The four-hour outage triggered a cascade of outages across numerous websites and services, including Slack, Quora, Medium and Business Insider. The outage had a substantial financial impact, with losses of $150 million for S&P 500 companies. This event highlighted the importance of system redundancy and the risks associated with reliance on a single vendor, prompting many companies to diversify their IT strategies.

3. Facebook outage: System failure

In October 2021, a system failure caused a massive global outage of Meta (formerly Facebook), affecting billions of users. Facebook, WhatsApp and Instagram were down for 6-7 hours, leading to a sharp decline in user engagement and advertising revenue. Meta's market value plummeted by $47.3 billion, and its CEO, Mark Zuckerberg, saw his personal fortune decline by approximately $6 billion. The company later revealed that the root cause was a faulty command, exacerbated by the glitch. This incident not only disrupted social connectivity around the world, but also served as a stark reminder of the vulnerabilities inherent in complex digital infrastructures.

4. Google outage: Storage problems

Tech giant Google experienced a major outage in 2020, lasting 45 minutes, due to an internal storage problem in its authentication system. The inability to free up space caused a system crash that affected a wide range of services, including YouTube, Google Drive, Gmail and Google Maps. Millions of users were unable to log in, leading to widespread frustration and a loss of $1.7 million in advertising revenue on YouTube alone. This outage illustrated the critical role of robust data management and storage solutions in keeping digital operations running smoothly.

5. DYN Outage: Overwhelming DDoS Attack

In 2016, DYN, a leading DNS provider, suffered a massive distributed denial of service (DDoS) attack. The attack, orchestrated through the Mirai botnet, used IP cameras and IoT devices to flood DYN's servers. This caused a major outage affecting numerous high-profile services, including Twitter, Reddit, Spotify, CNN, Netflix and Amazon, mainly in Europe and North America. The attack highlighted vulnerabilities in internet infrastructure and the potential for widespread disruption from cyber threats.