Enterprises are investing heavily in high availability (HA) and disaster recovery (DR). Yet, many continue to experience outages affecting mission-critical applications.
That is the central finding of SIOS Technology Corp.’s 2026 State of Application Resilience Survey. The study surveyed more than 250 IT leaders across North America and the United Kingdom.
The findings point to a growing gap between investment in resilience technologies and the ability of organizations to maintain continuous application availability.
As hybrid and multicloud infrastructures become mainstream, traditional approaches to availability and disaster recovery are also facing new operational challenges.
Downtime Remains a Persistent Enterprise Problem
The survey found that 76% of organizations experienced at least one outage lasting more than 10 minutes during the past year, despite having HA/DR protection in place.
The finding is significant because HA/DR investments are designed to reduce the business impact of infrastructure failures and application disruptions.
The continued prevalence of outages suggests that simply deploying HA and DR technologies does not guarantee application resilience.
Modern applications often depend on multiple infrastructure layers. These can include physical servers, virtual machines, cloud platforms, databases, networks and third-party services.
A failure in one component can therefore create cascading availability problems.
Hybrid and Multicloud Complexity Is Changing the Resilience Equation
Hybrid and multicloud environments have become the norm for many enterprises.
Nearly seven in ten organizations surveyed operate critical applications across hybrid infrastructures. Only 2% operate exclusively on-premises.
This architectural shift creates new challenges for IT teams.
Applications may need to remain available across different operating systems, cloud platforms and infrastructure environments. Each environment can also have different management tools, policies and recovery mechanisms.
Consequently, application resilience increasingly depends on how effectively organizations coordinate these heterogeneous environments.
The survey indicates that configuration and management complexity has overtaken cost as the leading HA/DR challenge.
Integration across increasingly diverse IT environments ranked closely behind it.
Confidence in Existing HA/DR Strategies Remains Limited
Technology investment does not necessarily translate into confidence.
Only about half of survey respondents said they were satisfied with their current HA/DR solutions. Many others were neutral or dissatisfied.
This suggests that enterprises are reassessing whether existing approaches can meet the requirements of modern applications.
The issue is not simply whether an organization has a disaster recovery platform or high availability technology.
IT leaders increasingly need to know whether those technologies can work reliably across complex environments, recover applications quickly and simplify day-to-day operations.
This is where application resilience is becoming a broader strategic consideration rather than a narrow infrastructure function.
Disaster Recovery Testing Has a Major Weakness
A recovery strategy is only as strong as an organization’s ability to execute it when an actual incident occurs.
Yet the survey found that only 7% of organizations conduct DR testing monthly.
Around one-third test annually, while 22% do not know how frequently their organizations conduct testing.
Infrequent testing can create substantial operational risk.
Recovery procedures can become outdated as applications, infrastructure and dependencies change. Staff responsibilities may also change over time.
Regular testing helps organizations identify these weaknesses before a real outage or disaster exposes them.
For enterprises running mission-critical workloads, testing should therefore be treated as an ongoing operational discipline rather than an occasional compliance exercise.
Cybersecurity Is Reshaping High Availability
The relationship between cybersecurity and availability is also changing.
The survey found that 72% of respondents either already use or would consider using HA clustering to streamline patch management.
The finding reflects an important shift in thinking.
Security patches are essential, but applying them to mission-critical systems can introduce operational risks. Organizations may need to balance security requirements with the need to keep applications continuously available.
HA clustering can potentially help organizations manage this tension by supporting maintenance activities while reducing application disruption.
As a result, cybersecurity and application resilience are increasingly becoming interconnected priorities.
Windows Dominates, but Mixed Environments Are Growing
Windows remains the dominant operating system for mission-critical applications among respondents.
However, organizations are increasingly operating mixed Windows and Linux environments.
This creates another layer of complexity for IT teams responsible for availability.
A resilience strategy designed around a single operating system or infrastructure model may not be sufficient for organizations managing heterogeneous environments.
Cross-platform capabilities and application-aware approaches are therefore becoming increasingly relevant.
The objective is not simply to protect servers. It is to ensure that the applications businesses depend on can continue operating despite infrastructure failures, maintenance activities or other disruptions.
Disaster Recovery Is Becoming a Strategic Investment
The survey also highlights where organizations expect to direct future technology spending.
Improving disaster recovery protection ranked second only to cybersecurity among planned IT investments over the next 18 months.
That positioning is important.
It indicates that enterprises recognize resilience as an investment priority rather than simply an operational expense.
The growing dependence on digital applications means downtime can affect revenue, customer experience, employee productivity and regulatory obligations.
As organizations continue moving workloads across cloud and hybrid environments, the cost of application disruption can also become harder to predict.
Investment in application resilience is therefore increasingly tied to broader business continuity objectives.
From Failover to Application-Aware Resilience
One of the most important implications of the survey is that enterprise resilience is evolving beyond traditional failover.
Modern applications have dependencies that extend across infrastructure, operating systems, databases, networks and cloud environments.
Simply switching workloads from one server to another may not be enough if the application itself cannot recover correctly.
Application-aware clustering approaches attempt to address this problem by considering the application and its dependencies as part of the availability strategy.
This can also help organizations simplify management across heterogeneous environments.
As hybrid and multicloud architectures continue to expand, the ability to manage resilience across different infrastructure environments will become increasingly important.
The Enterprise Resilience Gap
The 2026 survey presents a clear paradox.
Enterprises have invested extensively in HA and DR technologies. Yet outages remain common, DR testing is inconsistent and confidence in existing strategies is far from universal.
At the same time, infrastructure environments are becoming more complex.
The result is an emerging application resilience gap: organizations may have resilience technologies in place, but those technologies do not always translate into the availability, operational simplicity and recovery confidence that businesses expect.
Closing that gap will require more than additional infrastructure.
Enterprises will need stronger testing disciplines, better integration across heterogeneous environments, simpler management models and resilience strategies that understand applications rather than treating infrastructure components in isolation.
For IT leaders, the message from the SIOS survey is straightforward: high availability and disaster recovery can no longer be viewed as separate infrastructure functions. They are becoming fundamental components of enterprise application strategy.
The findings discussed in this article are based on SIOS Technology Corp.’s 2026 State of Application Resilience Survey, which surveyed more than 250 IT leaders across North America and the United Kingdom.