Why backup validation is the most overlooked part of OT disaster recovery
Despite what we tend to imagine, the vulnerability most likely to compromise OT resilience is not backup.
In the majority of organisations, backup is familiar, well-documented and well-monitored. Yet there is one aspect of recovery planning that even mature environments frequently fail to invest in properly. This is generally not through neglect, but because it is harder to schedule, riskier to test and far easier to put off
‘for tomorrow’.
The step that turns system recovery from a comforting idea into a capability you can trust in a crisis is validation. Not simply confirming that a backup looks clean, but proving that the system itself can be restored, booted and returned to service on the hardware it must actually run on.
In speaking with customers across OT environments, this is often the point where unexpected recovery challenges surface.
Verification vs validation - and why the distinction matters to your recovery
Almost all tools report that a backup has completed successfully. Some go a little further and run integrity checks or boot an image to the point where a login screen appears. These are useful confirmations, but they only answer the question: “Does the backup file look intact?”
This is verification.
Validation asks a far more important question: "Can we actually recover this system quickly and dependably, in its real operational environment?"
Answering this means checking how the backup restores, how it handles your drivers and existing hardware, how applications behave once they’re running and whether the restored environment is genuinely ready to return to service.
So where backup verification tells you what’s been saved, validation tells you what you can recover. It transforms fingers-crossed optimism into a peace-of-mind-inducing, dependable and reproducible outcome.
It’s the step that determines how well you’re able to respond when something actually does go wrong.
Why does validation so often get postponed?
As teams responsible for ensuring fast, untroubled OT recovery know well, validation is often the hardest part of recovery readiness to maintain consistently.
Why? Recovery testing takes time and involves coordination across teams. In OT environments, even arranging access to production hardware can be a challenge. So when backups appear to run smoothly week after week, it’s tempting to settle for the assumption that ‘everything is fine’.
But in practice, many recovery failures happen not because backups are missing, but because restores have not been proven under real conditions.
Validation. The cornerstone of disaster recovery
The number of restore points you retain doesn’t matter. Nor does the speed of your storage or the sophistication of your reporting. And while provider success messages are helpful, they can’t confirm how your own environment will behave.
A backup is theoretical until you validate it. Up until then, you’re relying on assumptions that may well prove false when confronted by ransomware, hardware failure or unpredictable updates.
By replacing the uncertain with the proven and predictable, validation strengthens confidence around your RTOs (recovery time objective) and RPOs (recovery point objective) and ensures your disaster recovery plan reflects reality rather than intention.
It shows you how your people, systems and tooling behave when recovery genuinely matters. And it aligns with a broader best practice move towards zero trust: don’t assume anything works until it has been tested.
The four layers of backup validation
At Macrium we see meaningful validation as comprising four layers, with each contributing to confidence in a different way.
Integrity checks
These are quick, simple and essential. They confirm that the backup file hasn’t changed since it was created and detect corruption, incomplete transfers or silent block-level errors.
They are an important baseline, but they only tell you about the file itself, not how the restored system will behave.
Virtual boot testing
Booting an image inside a virtual environment shows whether the operating system initialises correctly and whether the applications and services that sit on top of it start as expected.
Many industrial and medical devices run older or embedded editions of Windows beneath the surface, and virtual testing provides a safe, predictable way to assess whether recovery is viable.
But virtual hardware isn’t real hardware, and that difference creates a vulnerability of its own.
Hardware restores
This is where practical issues often make themselves known.
Restoring to physical hardware, especially when it differs slightly from the original, exposes driver mismatches, chipset quirks, UEFI differences, timing issues and dependencies that simply don’t appear in virtual environments.
In OT estates, where machines may rely on discontinued controllers or bespoke drivers, these discrepancies can be significant. Validation at this layer catches these failures before they become incidents.
This is something manufacturers like Husco have highlighted, where recovery confidence depends not just on backups existing, but on knowing systems can return quickly in real operational settings.
Full disaster recovery drills
This final layer tests people as much as systems.
A DR rehearsal shows how your team works under pressure, how clear your documentation is, whether the correct backup sets are available and how recovery behaves when applied across several systems at once.
It is the closest possible enactment of a real event and the only truly reliable way to measure your recovery capability.
So what goes wrong when validation is missing?
When validation is skipped, problems are left to surface when you can least afford to have them do so.
Systems that refuse to boot on replacement hardware. Corrupt backups that appeared normal during routine checks. Images that start but fail as soon as applications load.
If none of these catches you out, then malware preserved inside older restore points, drivers for legacy devices no longer being available online, or recovery workflows that break when applied across several machines quite probably will.
Why validation is especially important in OT environments
For OT teams, validation should never be viewed as optional.
OT may depend on specific drivers, calibration files or hardware behaviours that must return in an identical state. Environments may operate offline or be strictly air-gapped, highlighting the criticality of the systems.
Downtime is likely to affect more than productivity, too. It may disrupt critical services, halt manufacturing or impact patient care, for example.
In such situations, verification alone tells you almost nothing. Unless recovery can be validated on the equipment that matters, it cannot be relied on in a real event.
Compliance, insurance and the shift towards provable recovery
Regulators and insurers are now asking as a matter of course not whether backups exist, but whether their restoration has been tested.
Frameworks such as NIS2 and sector-specific resilience standards expect demonstrable evidence of recoverability: what was tested, how it performed and what has been improved.
Consequently, for many organisations this validation record has become a core element of governance and audit readiness.
Building a practical validation habit
Validation does not need to be disruptive.
The most effective teams build it into their rhythm: running routine integrity checks, scheduling regular virtual boots for key systems, performing periodic hardware restores and running occasional DR drills as part of continuity planning.
Small, repeatable exercises build resilience far more effectively than a single large test every few years.
Stop trusting success messages and start validating recovery
You’ll already be treating continuity seriously, and almost certainly have the tools and processes in place to support it.
Validation is the step that removes uncertainty, reduces downtime and gives you confidence that your systems will return exactly as you expect when an incident occurs.
It’s the process that transforms your backup strategy into a dependable recovery capability.
Want to learn more about strengthening validation in your recovery strategy? Watch our on-demand webinar, From Prevention to Recovery: Mastering Backup Strategies for Cyber Resilience. For any questions about your own environment, contact our team.
Author: Brooke Watson, Content Marketing Manager, Macrium
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