What happens when a system reaches End of Life (EOL)?
For years, legacy systems have supported the growth of organizations.
These are platforms that sustain core processes, critical applications, and complex integrations, often custom‑built and deeply embedded in day‑to‑day operations. The problem is not their existence.
The problem begins when they reach End of Life (EOL) or End of Support (EOS).
When a vendor declares the end of support for a technology, as has happened with several versions of solutions from Microsoft, Oracle, or VMware, the impact goes far beyond the simple absence of updates. It means there are no longer security patches, critical fixes, or official support. The system may remain operational, but it starts functioning outside the manufacturer’s protection perimeter. And in an increasingly demanding regulatory and cybersecurity context, this stops being a technical issue and becomes a risk‑driven decision.
It is common to hear that a given system “is stable” and that changing it represents a greater risk than keeping it. This perception ignores an essential point: stability is not the same as sustainability. A legacy system at the end of its life accumulates technical debt, increases reliance on specific knowledge — often concentrated in just a few people — and limits the ability to integrate with new platforms, APIs, and cloud models. As the market evolves, these limitations become real barriers to innovation.
Security risk is one of the most critical dimensions. Unsupported platforms become preferred targets precisely because identified vulnerabilities are no longer fixed. For organizations subject to strict regulatory requirements, keeping EOL systems can jeopardize audits, certifications, and even institutional reputation. The cost of a security incident usually far exceeds the investment required for modernization.
There is also a less visible, yet equally relevant, financial impact. Corrective maintenance of older environments is typically more expensive and less predictable. Hard‑to‑replace components, fragile integrations, and manual interventions increase operational costs over time. What initially seemed like savings — delaying modernization — turns into a structural burden.
It is also important to demystify the idea that modernizing means migrating everything abruptly.
Technological transformation should not be impulsive or driven by trends. It should be structured, phased, and aligned with business priorities. A rigorous assessment process allows organizations to map dependencies, evaluate real risks, identify quick wins, and design a sustainable roadmap. In many cases, the strategy involves hybrid models, progressive replatforming, or environment consolidation, reducing complexity without compromising continuity.
Postponing the decision until a critical failure, a negative audit, or a security incident arises is acting under pressure. And decisions made under pressure are rarely strategic. The right time to assess a legacy environment is before urgency sets in.
Link has been supporting organizations in this process with an approach centered on architecture, risk, and financial impact. The first step is not to propose a migration. It is to understand the client’s context: which systems are truly critical, what the dependencies are, where the real risks lie, and what scenarios make sense over the next three to five years. From there, a plan is built that balances modernization, operational continuity, and budget control.
Legacy systems are not, by definition, a mistake. They were solutions appropriate for their time. The challenge lies in ensuring they remain aligned with current security, compliance, and agility requirements. Keeping an end‑of‑life system is a strategic decision — whether consciously or by omission.
The fundamental question is not whether the technology still works. It is whether it continues to protect and support the business with the level of resilience demanded by today’s context.
