The 2026 SIOS High Availability (HA) Survey shows that many large enterprises are still struggling with downtime and only moderate confidence in their current resilience strategies.

Key data points from more than 250 IT leaders in North America and the UK:

• 76% of organizations experienced at least one downtime event of more than 10 minutes for their most critical applications in the past 12 months.
• Nearly 1 in 4 (23%) had 3–4 such downtime incidents in a single year.
• 5% of respondents have no HA protection at all for mission-critical applications.
• Only about half of respondents say they are somewhat or very satisfied with their current HA/DR solutions.
• 11% are somewhat or very dissatisfied, and more than a third are neutral.

At the same time, environments are getting more complex:

• Only 2% run critical applications fully on-premises.
• Nearly 70% use hybrid setups (mix of on-premises and cloud).
• Most are multicloud, using different cloud vendors for different applications.
• 86% run critical workloads on Windows, while a wide range of Linux distributions (e.g., Red Hat at 32%, Oracle Linux at 18%, Ubuntu at 16%, SUSE at 12%) are also in play.

This combination of frequent downtime, mixed satisfaction, and increasingly hybrid/multicloud, mixed-OS environments suggests that many legacy failover and DR strategies are not keeping pace with modern workloads. Organizations are looking to reimagine their HA/DR approach with more application-aware, cross-platform solutions that can better align with how they actually run their critical systems today.

The survey makes it clear that complexity and weak testing practices are two of the biggest obstacles to effective HA/DR.

Top implementation and management challenges

• Complexity of configuration and management is the number one issue, cited by nearly 44% of respondents.
• Integration with existing systems and applications is the second biggest challenge at 37%, reflecting the reality of mixed Windows/Linux, hybrid, and multicloud environments.
• Other concerns include ensuring reliable failover and recovery, keeping up with testing and updates, and cost—but cost is actually secondary to complexity and integration.

Many organizations are running a wide mix of critical workloads—databases, ERP, financial and banking systems, healthcare records, manufacturing and building management systems, and more—across different platforms. Traditional clustering tools often require separate approaches for Windows and Linux, which adds to the operational burden.

DR testing frequency and risk

• Only 7% of organizations test disaster recovery monthly, which is the cadence many DR frameworks recommend for mission-critical systems.
• About one-third test only annually.
• 22% of respondents don’t know how often DR tests are performed, indicating poor communication or inconsistent processes.
• Roughly 1 in 5 organizations lack consistent or recorded DR testing.

The result is a gap between what’s on paper and what will actually work in a real incident. Many teams have DR plans that are more theoretical than proven. This is one reason why enterprises are increasingly interested in modern, application-aware clustering solutions that can simplify configuration, standardize HA across mixed environments, and make testing and failover more predictable and manageable.

The survey shows that cybersecurity and application resilience are now closely linked priorities, and patch management is emerging as a key HA use case.

Spending priorities reflect this shift:

• Enhancing cybersecurity is the top IT spending priority related to HA/DR.
• Improving application disaster recovery protection ranks second, ahead of data analytics (31%), infrastructure upgrades (26%), and new software deployments (24%).
• Nearly 75% of respondents label DR as a medium or high priority.

HA clusters for patch management

Organizations are increasingly using HA clustering to reimagine how they handle security patches and updates, aiming for faster remediation with minimal disruption:

• 14% already use HA as an integral part of their patch management process.
• 31% would consider using HA clusters to improve patch management.
• 27% are interested in learning more.

In total, 72% of respondents either already use HA for patching or are open to it. The appeal is the ability to:

• Perform rolling updates and patches with near-zero downtime.
• Test patches on one node while keeping services available on another.
• Accelerate vulnerability remediation without taking critical applications offline.

Vendors like SIOS are leaning into this trend with application-aware clustering that supports:

• Mixed Windows and Linux environments.
• On-premises, virtualized, and public cloud deployments.
• Enterprise databases, ERP platforms (including SAP), healthcare, financial, aviation, and other vertical applications.

By combining automated failover, rolling patch capabilities, and cross-platform support, modern HA solutions are helping organizations rethink resilience as part of a broader cyber resilience strategy, rather than treating security and availability as separate efforts.