Legacy IT infrastructure is like an old car: It might be your favorite, it might still run, but it’s inefficient, unreliable, and lacks the safety features of a newer model.

While legacy IT systems may still be functional, they can hold a business back from reaching its full potential – especially if market competitors are busy upgrading their own systems. Companies need to carefully evaluate the costs and benefits of keeping legacy systems in place and develop a plan to modernize their IT infrastructure. Investing in a modern data center solution can, over time, improve business agility, security, and your organization’s bottom line.

Legacy data center equipment simply won’t cut it anymore for jobs such as genomic mapping, generative artificial intelligence (genAI) apps, and other large language model (LLM) workloads. IT transformation is all about evolving to stay agile and intentionally moving from old to new at certain points during an IT system's lifetime. Overall performance, capacity, and networking can become bottlenecks in systems that cannot move large data loads efficiently.

Legacy IT systems can be a real burden to enterprises for a number of reasons, some more obvious than others.

Increasing costs – both obvious and hidden

Original costs may have been lower in the past, but maintaining legacy systems can be expensive. A large portion of IT budgets, sometimes 60% to 80%, can be dedicated to simply keeping these old systems running. This diverts funds from investments in new technologies that could improve efficiency and innovation.

Next-generation servers, storage ,and networking are inevitably faster and more efficient as new models are made available. Legacy equipment, depending upon how old it is, has intrinsic costs simply for being what it is: older technology needing special support, parts, and software apart from the rest of the system.

“Legacy on-premises equipment can cost you, whether the velocity is too slow for delivery, whether there are continual hardware issues, bandwidth and constraints, or increasing costs, and so on,” Armon Petrossian, co-founder and CEO of Coalesce.io, maker of data management automation software for Snowflake, told SDXCentral. “A lot of companies are still using legacy equipment. If you follow the news, if you follow stock prices, you would think everybody's on the cloud today. That couldn't be further from the truth.”

Legacy systems often have hidden costs associated with maintaining outdated infrastructure, including power consumption and cooling requirements. Newer, more energy-efficient technologies can significantly reduce these costs.

Limited functionality for newer applications

Lost functionality from old legacy software and hardware can cost the owners of an IT system in a number of ways, impacting both their finances and overall business agility.

Most of the time, legacy systems will not have the features and functionality that businesses need to compete in the current marketplace. This is especially true when it comes to next-generation applications using LLMs and machine learning (ML) for AI-dependent applications. Enterprise servers, storage and networking hardware, and software manufactured before about 2016 were not designed with scaled-up data workloads in mind – especially workloads for genAI, which just started to take off in 2021. This can hinder growth and force companies to invest in additional hardware or software just to maintain their current operations.

Legacy systems are also more prone to failures and outages due to aging hardware and software. This downtime disrupts operations and leads to lost revenue, especially for critical business functions. Additionally, data loss from system crashes can be costly to recover from.

Employees may have to resort to manual processes and workarounds to complete tasks that could be automated with newer software. This is time-consuming and error-prone, impacting overall productivity.

Finding and accounting for it all

Legacy software and hardware tends to be forgotten, intentionally sidelined by new staff or superseded by newer equipment and software, but it often remains online, available to use and sucking power. Often it is difficult to find and account for old tools, applications, and hardware – especially for multinational companies with widespread locations.

“Here's the thing about legacy software (and hardware): you've got to know where it lives,” Thomas Johnson, co-founder of collaborative development platform-maker Multiplayer, told SDxCentral. “You've got to know the quirks, you've got to gather the intelligence about older items. People who used legacy equipment and software come and go.”

“It's like: 'there's probably some documentation over there on that network driver in that place or whatever, and maybe there's a sketch over there' – it's all just distributed. So to put it in a central place is critical because your infrastructure is getting more complex, too. All that documentation, that knowledge, is going to get lost if you're not careful,” Johnson said

Increased security risks

Legacy environments can be a security nightmare for security operations (SecOps) staff. Older systems often lack the latest security patches and are incompatible with modern security tools, making them prime targets for attackers. Legacy systems also may be vulnerable to security breaches because they may not have the latest security patches or be compatible with modern security protocols. This can put a company's data at risk.

Legacy systems were built with the security standards of a bygone era. They often lack the capability to implement modern security features such as multifactor authentication (MFA), encryption protocols, and robust access controls. This makes them vulnerable to known exploits, creating easier targets for attackers.

Vendors typically stop providing security updates and patches for older software and hardware. These unpatched vulnerabilities create gaping holes in the system's defenses, allowing attackers to exploit them and gain unauthorized access.

Lack of flexibility and support

Legacy systems are often inflexible and difficult to update. Software providers eventually stop supporting legacy versions after a set period of time. This can make it hard for businesses to adapt to changing market conditions or implement new business processes. The rigidity of legacy systems can slow down product development and make it difficult to integrate with newer technologies.

Lack of skilled talent for outdated systems

Finding skilled IT professionals who can work on outdated systems can be difficult. Younger generations of IT workers may not have the experience or knowledge required to maintain these systems.

Working with outdated and clunky systems can be frustrating and demotivating for employees. This can lead to decreased morale, higher turnover rates, and reduced productivity.

Legacy systems cause 'technical debt'

Technical debt refers to the concept of choosing an easier or faster solution now, knowing it will likely cause problems or require more work later. It's like taking on a loan to finish a project quickly but with the understanding that you'll need to pay it back (with interest) in the form of future maintenance and rework.

When data center operators migrate to a more modern infrastructure, they encounter several technical debt challenges. These include:

• Legacy hardware and infrastructure: Outdated technology in data centers can hinder the data center’s ability to produce results. Legacy hardware and infrastructure increases energy costs and the risk of unplanned outages.
• Data control and transformation: Transforming operations involves getting control of all corporate data. This is time-consuming and expensive to pull off while maintaining normal operations. Enterprises must focus on efficient data management to break free from technical debt.
• Operational transformation: Organizations must break the cycle of technical debt by adopting new practices. For example, a hypothetical government agency with 30,000 devices nearing end-of-support faces major risks. Their existing processes may take too long to refresh all devices, leaving them at risk for an extended period.

IT managers need to take frequent rolls of all of the enterprise's equipment and software to determine what needs to be ushered out – and what needs to be rolled in – at any point in time.