Legacy systems defined: examples, main problems and solutions

In the digital age, “move fast and break things” is the mantra. But behind the modern interfaces and digital bravado of many organizations are relics of the past: legacy systems. These legacy systems, sometimes called legacy applications, power critical operations and are deeply intertwined with established business processes.

However, the challenge of maintaining legacy systems can become overwhelming, especially when these outdated technologies struggle to keep pace with today's rapidly evolving technological environment. Is it time to consider replacing a legacy system?

Let’s pull back the curtain on legacy systems – why they persist and the potential pitfalls they present.

What is a legacy system?

Let’s start at the beginning: what is a legacy system? Basically, it is outdated software and other technologies that companies continue to use in their organizations despite the many problems they are causing. Too often, tools have become so deeply integrated into the organization's structure and procedures that both employees and leaders don't even consider replacing them with updated models.

There are many reasons why people continue to use old systems. They may have invested significant time and resources in maintaining these systems. Furthermore, there is often a fear of having to learn and use tools that are unfamiliar. Other times, the system seems simply irreplaceable.

However, these reasons should not stop you from considering adopting new software. This is because it is generally a much better solution than continuing to rely on legacy systems, which are riddled with problems.

According to the AppDynamics 2020 Transformers Report: COVID-19 Special Edition , 66% of IT professionals reported that the COVID-19 pandemic “exposed weaknesses” in their digital strategy. And many technology problems occur because organizations rely on legacy systems.

Examples of legacy software and systems

Legacy systems, often referred to as legacy applications, continue to play essential roles in many IT architectures. Let's look at some real-world examples of legacy systems to understand them better.

Old database systems

• Hierarchical databases : In the early days of databases, hierarchical systems such as IBM's IMS (Information Management System) dominated. They followed a parent-child structure. Although innovative at the time, their inflexibility with complex many-to-many relationships makes them less suitable today.
• Relational databases : You may still find older versions of popular relational databases, such as Oracle 8i or Microsoft SQL Server 2000, in some organizations. Although state-of-the-art in their day, they lack the features, efficiency, and security of modern versions.

Outdated enterprise software

• ERP Systems : First-generation ERP (Enterprise Resource Planning) systems, such as SAP R/2, had a monolithic architecture. Although comprehensive, these systems often suffer from rigidity and integration issues with newer technologies.
• Custom software : Many companies still use proprietary software developed decades ago, adapted to the needs of the time. They may be in outdated languages ​​like COBOL, making maintenance and updates difficult.

Obsolete hardware infrastructure

• Mainframes : Despite the rise of cloud computing, some organizations still rely on mainframes, the large, high-performance computers of the 1960s and 1970s. IBM's zSeries is a classic example. Although robust and reliable, they often lack the agility and scalability of modern solutions.
• Older Servers : Physical servers from the late 1990s or early 2000s may still operate in some server rooms, running older software and operating systems. They often need specialized knowledge for maintenance.

Older operating systems

• Windows XP : Released in 2001, Windows XP has become ubiquitous in business and for home use. However, with Microsoft ending support in 2014, XP systems are now vulnerable and missing features of modern operating systems.
• UNIX variants : Although UNIX-based systems such as Linux continue to thrive, older variants of the UNIX operating system (e.g. SunOS, AIX) face decreasing support and compatibility issues with new software.

By exploring these legacy applications and understanding the challenges of maintaining legacy systems, organizations can make an informed decision about whether to embark on a software modernization journey. This could involve upgrading existing infrastructure or replacing the entire legacy system with more modern and efficient technologies.

In the end, these legacy systems are a testament to their longevity and their fundamental role in shaping today's technological landscape. However, it is important to recognize its limitations. Organizations often struggle to balance respect for the history of these systems with the practical need to modernize them.

Legacy technology has persevered, but at some point it must give way to more agile and capable solutions. The trick is to determine when that time will come.

7 main problems associated with legacy systems

Modern IT infrastructures can be a tangled web of new and old systems. To navigate this complex terrain, organizations need to identify not only the strengths of these technologies, but also their vulnerabilities. As we explore the world of legacy systems, we uncover a number of pressing concerns that companies should be aware of.

These issues range from immediate security risks to general business inefficiencies. Let's take a closer look at the top seven challenges that legacy systems can create in a company's technology landscape.

#1 Security

Cybercrime is on the rise. Data breaches , ransomware attacks and cybersecurity issues are becoming increasingly prevalent as hackers become more sophisticated in their approaches. While there is no silver bullet when it comes to preventing cybercrime, there are circumstances that make it more likely — and put organizations at risk of it occurring.

Legacy systems, as you may have guessed, are one of them. Outdated hardware and software are more susceptible to cyberattacks. This is because vendors prioritize their up-to-date models when releasing upgrades and updates, ones that take into account the latest malware iterations and protect against issues. However, when you rely on old, outdated technology, you won't receive these updates, thus putting your entire business at risk.

Legacy systems also tend to lack newer, more advanced features like firewalls and encryption protocols. Again, cybercriminals can exploit these weaknesses and hack systems. Additionally, they may not be compatible with more up-to-date security tools and protocols, leaving them even more vulnerable to threats.

#2 Expensive maintenance

Many business leaders assume that updating software is exorbitantly expensive. In reality, it is often a much less expensive solution than trying to maintain outdated software. Legacy systems require extensive maintenance, and you will very well find that the costs of keeping them running are high – much more expensive than it would cost to simply overhaul your software and hardware.

Additionally, you can continue to invest money in your older systems, but they will never reach the quality level of newer models. Consequently, you are essentially wasting your funding on technology that will never meet the necessary standards.

#3 Inefficiency

"Slow." This is how many workers describe legacy systems. Despite being used for years and years, this technology continues to frustrate employees in all departments.

This is because legacy systems tend to be extremely inefficient. Long loading times , delays, and more — this is how these tools are often characterized. While they may have been a solid solution in the past, the software slows down over time. And since manufacturers no longer release updates, there's no real way to resolve the issues other than futilely trying to mitigate them.

This often negatively impacts employee productivity, creating delays and setbacks that make processes inefficient.

#4 Incompatibility

Your company likely uses a variety of technologies, and some systems are newer and more advanced than others. When you try to combine older systems with newer systems, a series of problems will inevitably occur.

Newer software and older software simply don't integrate well, and because of these incompatibilities, you will likely find that you need to use more systems than you would otherwise, as more modern models offer a multitude of features that support a wider range of processes.

#5 Data Silos

This issue is related to incompatibilities. When you try to rely on outdated systems, you will use them in isolation as they will not integrate properly. This creates data silos which means information is isolated in specific systems.

This is extremely problematic for organizations of all types and sizes. This means employees must turn to many different tools to find what they need, while modern systems like ERPs store this data in a single location. This is a huge waste of time – not to mention extremely frustrating.

#6 Lack of support

Depending on their age, most legacy systems are no longer supported by manufacturers because they are no longer sold. This means that if you have questions or encounter problems with the software, the vendor cannot help you resolve the issue. You may receive support from third-party providers, but even this will become increasingly unlikely as the technology becomes obsolete.

#7 Compliance

Organizations must adhere to regulations governed by the territories in which they operate. Take, for example, the General Data Protection Regulation (GDPR). This law concerns data privacy in the European Union and establishes rules on how companies can treat information. When companies use outdated technology, they are more than likely to encounter problems remaining compliant, as older systems do not take into account the latest compliance regulations.

Solutions to overcome legacy systems challenges

As companies' technology stack continues to change, legacy systems can easily become obstacles that hinder innovation and efficiency. While their continued presence pays homage to an organization's history, the problems they create cannot be ignored.

Addressing these legacy system challenges requires a careful and deliberate strategy. In the following section, we will explore several strategies that organizations can use to address the obstacles and limitations imposed by legacy systems.

The goal is to explore various legacy systems modernization strategies, such as modernizing, transitioning, or integrating these legacy technologies so that they no longer obstruct operational progress and growth. With the right approach, legacy technology need not be a barrier to future success.

Modernization of legacy systems

The idea behind modernization is to update and refine the existing legacy system, giving it new life with today's technological advancements. It's like renovating an old house by incorporating modern amenities.

Benefits

• Preserves the essential functions on which the organization depends. No need to start from scratch.
• It may cause less disruption than ripping out everything and doing a complete overhaul.
• It makes the system more flexible, adaptable and scalable for the future.

Disadvantages

• It can be an expensive and time-consuming process. Significant investment is required.
• It won't necessarily address fundamental flaws if the underlying architecture is outdated or inherently problematic. Lipstick on a lipstick on a pig backdrop.

Migration

Migration, a key component of legacy system modernization strategies, takes a more radical approach: completely transitioning the legacy system to newer systems while ensuring a successful data migration.

Main steps

• Data migration – Transfer all critical data from the old system to the new one. This is a delicate process that ensures nothing gets corrupted or lost in the shuffle.
• Transition period – Run legacy and new systems in parallel for a while. This allows time to resolve any issues and ensure that the new configuration does not disrupt normal business operations.
• Staff training – Employees need to be trained and familiarized with the new system. This is essential for smooth adoption across the organization. We can't have people fumbling around without knowing how to do their jobs.

Integration with New Systems

Instead of abandoning the legacy system entirely, integration aims to make it work well with new modern solutions.

• Using Middleware – Middleware acts as a translator between old and new systems. It bridges the technical gap so they can talk to each other and work together harmoniously.
• Custom APIs – Application programming interfaces can be developed to allow different software platforms to interact. This allows organizations to get the best of both worlds – maintain critical legacy functions while benefiting from flashy new features.

Retirement in phases

For organizations that aren't ready to throw off the Band-Aid, phased retirement provides a more gradual transition approach.

• The legacy system does not shut down overnight. Instead, it is slowly retired as the new system progressively takes over its functions.
• This minimizes disruption to operations and gives the organization plenty of time to adapt. Less shock to the system.
• Having a detailed transition plan is essential. This roadmap describes the step-by-step process of eliminating the old system and introducing the new one.

Conclusion

Controlling legacy systems is crucial – not only because of their historical role, but even more so to deal with the problems they cause in today's rapidly changing digital world. While these aging systems are a testament to past achievements, their limitations can actually hamper future innovation and growth.

Therefore, the real value is not just recognizing the existence of these systems, but taking decisive action – modernizing, migrating or integrating them with newer solutions. This allows organizations to not only protect current operations but also pave the way for future success.

The goal is to ensure your technology base remains robust and adaptable and keeps up with the modern era. Don't let legacy systems remain stuck in the past. By taking the right steps, they can propel their organization into the future with confidence.

Common questions

What is the main reason companies still use legacy systems?

The main reason companies still use legacy systems is the cost and effort required to replace them. Data migration, staff retraining, and potential downtime during transitions can be costly and disruptive. Companies are reluctant to fix what still works functionally despite limitations.

How does technical debt from legacy systems impact business?

Technical debt leads to long-term costs from inefficient maintenance and integration workarounds. Reduces the agility to adopt new technologies. Outdated systems cannot take advantage of innovations like AI, harming competitiveness.

Are legacy systems always a bad choice for companies?

Not necessarily. They can perform restricted functions reliably and at low cost. Forcing a change when the business impact is minimal may not be financially sensible. But limitations need to be strategically assessed.