Best On-Premises Operating Systems of 2025

TrueNAS is the world's most deployed storage software. TrueNAS is a universal data platform that allows users to easily adopt a modern, open source approach to storing and protecting their growing data. TrueNAS is open source and harnesses the power of the legendary ZFS file system to provide unified storage (File, Block Object, and Apps) with the reliability and performance demanded by virtualization, backup, and many other data-heavy workloads.

OpenIndiana is an operating system developed for the illumos community, originating from the UNIX family of operating systems, which can sometimes present a level of complexity. However, with a bit of guidance and knowledge of the fundamentals, you will discover that it offers some of the most user-friendly tools available. Like many UNIX-based systems, it can be entirely managed through a Command Line Interface (CLI) shell, while also providing support for a graphical user interface (GUI) system. The CLI offers various shells, with the primary ones being ksh93 and Bash, and it also accommodates the original SunOS SVR4 commands, the command syntax familiar to BSD users, along with a significant portion of the GNU userland commands that Linux users often utilize. This flexibility allows users to choose from a variety of commands within their shell configuration, enabling a personalized environment that suits their preferences. Ultimately, OpenIndiana stands out for its adaptability, making it accessible to a wide range of users, from novices to seasoned professionals.

Windows Server 2022 brings forth enhanced multi-layered security features, hybrid functionalities with Azure, and a versatile application platform. Begin by fortifying your organization's security framework right from the operating system. Expand your data center capabilities to Azure to achieve improved IT efficiency. Equip developers and IT professionals with a robust application platform designed for building and deploying a range of applications. Discover how using Azure can lead to significant cost reductions through programs like the Azure hybrid benefit and extended security updates. Transform your workloads using Azure, recognized as the reliable cloud solution for Windows Server. Seamlessly connect your on-premises Windows Servers to Azure via Azure Arc. Upgrade to the latest operating system to enjoy superior security, enhanced performance, and increased value. By leveraging Azure, you can now fully tap into the myriad advantages of cloud computing. Starting is free, enabling you to manage servers, clusters, hyper-converged infrastructure, and Windows 10 PCs effectively with Windows Server, making your transition to cloud services smoother and more efficient than ever before.

NomadBSD is a persistent live operating system designed for USB flash drives and is built upon FreeBSD®. It features automatic hardware detection and setup, making it ready for immediate use as a desktop system, while also serving purposes such as data recovery, education, or testing hardware compatibility with FreeBSD®. The images suitable for both 64-bit and 32-bit machines can be stored on a 5GB USB flash drive, and a system equipped with a 1.2GHz CPU and 1GB of RAM should handle NomadBSD adequately. Users can boot the system via either BIOS or UEFI interfaces. Recently, a new versioning scheme has been introduced, formatted as FFfX-YYYYMMDD, where FF indicates the major two-digit version of FreeBSD, 'f' represents the minor version, and 'X' denotes the status as ALPHA (A), BETA (B), RC, or RELEASE (R), followed by the date. This updated versioning allows for the distribution of images featuring various FreeBSD versions, enhancing the flexibility and usability of the system. Additionally, this approach ensures that users can select the specific version that best meets their needs.

NetBSD is a completely free, rapid, secure, and exceptionally adaptable Unix-like open-source operating system. It caters to an extensive array of platforms, ranging from robust servers and capable desktop computers to portable and embedded gadgets. First introduced in 1993, NetBSD's code has gradually permeated numerous unexpected environments due to its longstanding reputation for quality, neatness, and reliability. This operating system is fundamentally rooted in 4.4BSD Lite2, which originated from the University of California, Berkeley. Unlike a typical "distribution" or variant, NetBSD has developed over several decades into a distinctive and comprehensive operating system within the BSD lineage, supported by a global community of developers. Users of NetBSD benefit from a straightforward, well-documented, and entirely cohesive UNIX-like experience that maintains a minimalistic approach while embracing a wealth of modern features and compatibility with contemporary hardware. This combination of attributes has made NetBSD a compelling choice for both enthusiasts and professionals alike.

The OpenBSD operating system is entirely developed by a community of volunteers. Funding for the development environment and various developer events is sourced through donations managed by The OpenBSD Foundation. These contributions play a vital role in ensuring the longevity and accessibility of OpenBSD as a free operating system. As a result, the OpenBSD project has integrated cryptographic features in multiple areas throughout the system. We insist that all cryptographic software utilized must be available without cost and come with favorable licenses. Direct use of cryptography encumbered by problematic patents is strictly avoided. Additionally, we prioritize sourcing such software from countries that offer favorable export regulations, as we are committed to adhering to international laws. Our decision-making process remains focused on technical excellence, avoiding political influences whenever possible. Ultimately, this commitment to both free software and legal compliance underscores the integrity of the OpenBSD project.

Unraid OS provides unparalleled management of your data, media, applications, and desktops, enabling users to leverage nearly any hardware configuration. It is particularly beneficial for video producers, streamers with large video collections, media editors, photographers, musicians, and music enthusiasts who want to minimize their upfront expenses. You can begin with just two drives and expand your storage incrementally as needed. Gamers who also operate media servers and prefer customizing their systems rely on Unraid to maintain their performance without compromise. Furthermore, designers, 3D animators, developers, and photographers utilize Unraid for storing large amounts of assets locally, ensuring quick and efficient access. You can also employ services like Apple Time Machine and Windows Backup to securely archive large volumes of data that aren’t frequently used. Beyond this, software engineers, game development studios, AR/VR designers, and educational institutions take advantage of Unraid to conduct tests across various platforms, operating systems, and devices, enhancing their workflow and productivity. This versatility makes Unraid a valuable tool for anyone looking to optimize their data management solutions.

OS108 is a rapid, transparent, and secure desktop operating system that is constructed on the foundation of NetBSD. The name derives from the fascinating fact that a byte consists of binary bits represented as 1s and 0s in 8-bit groups, along with the intriguing distance between the Earth and the Sun being approximately 108 times the Sun's diameter. We are continuously seeking contributors who wish to engage with the project in various capacities. Even if you lack development skills, you can still make a valuable contribution by creating how-to guides, user-oriented documentation, and participating in support forums to assist fellow users. Your involvement can significantly enhance the community and improve the overall experience for everyone involved.

It encompasses all the essential software necessary for your everyday activities—such as email, internet browsing, document editing, gaming, and a plethora of additional applications. MidnightBSD, supported by a small yet passionate group of developers, aims to build an accessible operating system that is available for everyone to use at no cost. This system is compatible with x86, AMD64 architectures, and can also be run as a Virtual Machine. While the FreeBSD project has established a robust server operating system, it frequently neglects the usability and performance aspects required for desktop environments. It is crucial to customize scheduling, resource allocation, security measures, and application support to better serve desktop users. Many BSD-based projects are designed primarily for server use or older systems, and while some offer FreeBSD with a user-friendly graphical interface, they still suffer from an underlying server-oriented structure. Our decision to fork FreeBSD was not due to any conflict, but rather because we saw it as an exceptional foundation to build upon. Ultimately, our goal is to bridge the gap between server efficiency and desktop user experience.

OmniOS is an open-source server operating system designed to include only essential features. Its native file system, ZFS, integrates a volume manager with robust data integrity protections. You can effortlessly share volumes using protocols like iSCSI, CIFS, and NFS. Additionally, OmniOS allows the execution of lightweight virtual machines running either OmniOS or Linux in containers, eliminating the traditional hypervisor's overhead while ensuring complete resource management. For those needing full hardware virtualization, it supports bhyve and KVM, allowing the operation of various guest systems including Microsoft Windows and FreeBSD. Network infrastructure can be virtualized through Crossbow, which offers virtual interfaces and switches, plus the option to allocate dedicated resources for specific applications. DTrace serves as a powerful dynamic tracing framework to facilitate troubleshooting across the software stack, enabling real-time instrumentation whenever needed. As an open-source project, OmniOS is self-hosting and its development is actively managed on GitHub, where contributors can submit pull requests, and anyone interested can access the source code to compile their own version of OmniOS. This environment fosters community involvement and transparency in the development process.

The latest release of DragonFly, version 6.2.2, introduces several enhancements, including hardware compatibility for type-2 hypervisors utilizing NVMM, an upgraded amdgpu driver, and the experimental feature of remote-mounting HAMMER2 volumes, alongside a variety of other updates. As a member of the BSD family of operating systems, DragonFly shares its roots with Linux and other BSD variants, adhering to the foundational principles and APIs of UNIX while also diverging in terms of development direction from FreeBSD, NetBSD, and OpenBSD. This divergence allows DragonFly to pursue unique innovations, such as its sophisticated HAMMER filesystem, which offers high performance, built-in mirroring, and historical access capabilities. Additionally, one of the standout features is the implementation of virtual kernels, enabling the execution of a complete kernel as a user process, which facilitates resource management, kernel development, and debugging in an accelerated environment. These features collectively position DragonFly as a distinctive option within its operating system category, appealing to users seeking alternatives beyond conventional solutions.

Enterprise-Grade Linux for Edge-to-Cloud Implementations. This collaborative open-source initiative is a Debian-based Linux distribution specifically designed for applications spanning from edge to cloud scenarios. It guarantees reliable performance and stability across devices, on-premises environments, and cloud infrastructures. eLxr offers a robust and secure distribution, built upon the innovations of the open-source community, featuring a reliable release and update schedule that supports extended lifecycles and long-term deployments. It is especially suited for applications with strict timing demands, utilizing preempt-rt kernel configurations to enhance low-latency responses and ensure tasks are performed within exact timeframes. This approach leads to improved determinism and predictability when compared to conventional Linux kernels. eLxr is designed with a reduced footprint, promoting optimal performance and resource efficiency while minimizing potential vulnerabilities. It encompasses all essential features and capabilities, ensuring the most effective use of system resources while supporting diverse deployment needs. As a result, users can expect a highly adaptable and efficient platform for various application requirements.

Security Onion serves as a robust open-source platform dedicated to intrusion detection, network security monitoring, and log management. Equipped with a suite of effective tools, it empowers security experts to identify and address potential threats within an organization's network. By integrating various technologies such as Suricata, Zeek, and the Elastic Stack, Security Onion enables the collection, analysis, and real-time visualization of security data. Its user-friendly interface simplifies the management and examination of network traffic, security alerts, and system logs. Additionally, it features integrated tools for threat hunting, alert triage, and forensic analysis, which aid users in swiftly recognizing possible security incidents. Tailored for scalability, Security Onion is effective for a diverse range of environments, accommodating both small businesses and large enterprises alike. With its ongoing updates and community support, users can continuously enhance their security posture and adapt to evolving threats.

VxWorks®, a leading real-time operating platform in the industry, provides all the performance, reliability, safety and security capabilities you need for the most critical infrastructure's embedded computing systems. VxWorks is a preemptive, deterministic RTOS that prioritizes real-time embedded applications. It has low latency and minimaljitter. VxWorks has many security features that address the evolving security threats connected devices face at every stage, from boot-up to operation to data transfer to powered off. VxWorks has been certified to IEC 61508, ISO 26262, and DO-178C safety standards. VxWorks is built on an extensible, future-proof architecture that allows you to quickly respond to changing market demands, customer needs, technological advancements, and preserves your investment.

Open source software and a universal router are key to democratizing the way we access networks. VyOS' vision is to revolutionize how we access networks, so that everyone can build the solutions they have always wanted, without limitations, restrictions, or prohibitive prices. We believe that internet access is just as important to human development as food, water, air, and healthcare. VyOS was founded by engineers for engineers. It is an open-source software company that makes it possible to access networks without restrictions or prohibitive fees. Through our open-source software and virtual platforms, we do this as VyOS. Stateful firewalls, zone based firewall, all types source and destination NAT (one-to-one, one-to many, many to many). For auditing, creating customized images and contributing, everyone has access to the entire codebase and build toolchain.

IBM i is a cohesive operating ecosystem crafted by IBM, which includes an operating system, database, middleware, and various development tools. This platform is designed for those who create and innovate, and now with the latest release of IBM i 7.4, users can take advantage of continuous availability through IBM Db2 Mirror for i. This update brings cutting-edge security features and seamless integration with technologies such as IoT, AI, and Watson, ensuring that mission-critical applications operate without interruption. Enhanced security measures align with the latest industry standards, safeguarding vital business applications and sensitive data. A new object-level auditing capability has been introduced, along with robust Open Source environments to facilitate the migration of additional applications to IBM i. The platform enables effortless integration with IoT, AI, and Watson, allowing businesses to maintain productivity around the clock, every day of the year. Users can also transfer virtual save media to and from the cloud, streamlining operations. Furthermore, the latest release simplifies the management of IBM i by consolidating frequently used tasks, making it even more user-friendly and efficient for organizations.

Experience a robust UNIX operating system and its associated tools that ensure unparalleled availability, reliability, and security for mission-critical HPE Integrity servers. By leveraging this highly integrated UNIX platform, you can enhance operational efficiency while maintaining the highest standards of reliability and security for your essential HPE Integrity servers. HP-UX creates a dynamic and secure environment, seamlessly integrated into mission-critical HPE Integrity servers, allowing you to address your specific UNIX demands. With four distinct operating environments, HP-UX is designed to cater to diverse needs effectively. The system also emphasizes comprehensive server security and management, incorporating HPE Systems Insight Manager, which provides essential functionalities such as power management, health monitoring, and deployment tools. Furthermore, it includes extensive performance analysis resources for both kernel processes and applications, ensuring optimal functionality. Safeguarding your organization’s most vital applications and services is crucial in maintaining your business's trajectory toward success. With these capabilities, you can confidently navigate the complexities of modern computing environments.

GhostBSD is a user-friendly, desktop-focused operating system that is derived from FreeBSD, featuring MATE, OpenRC, and a collection of OS packages to streamline the user experience. It comes preloaded with a variety of essential software, enabling users to maximize its capabilities right from the start. Utilizing the GTK environment, GhostBSD offers an aesthetically pleasing interface and a comfortable experience that aligns with modern BSD platforms, fostering an authentic Unix work environment. Built upon FreeBSD's foundational code, its lineage traces back to the Unix Research at the University of California, Berkeley, where it was historically known as "BSD Unix" or "Berkeley Unix." In contemporary terms, it is commonly referred to as BSD, which stands for Berkeley Software Distribution. The main objective of the project is to merge security, privacy, stability, usability, openness, and freedom, ensuring that it remains accessible to all at no cost. Additionally, the user experience is further enriched by tools such as Networkmgr, which are specifically developed as part of the GhostBSD initiative, contributing to its seamless functionality and user satisfaction. This commitment to continuous improvement and user-centric design sets GhostBSD apart in the realm of operating systems.

Oracle Linux provides a comprehensive and open operating environment that combines virtualization, management, and cloud-native computing tools along with the operating system in a unified support package. It maintains full binary compatibility with Red Hat Enterprise Linux, ensuring seamless application performance. You can browse the catalog to locate details about independent software vendors (ISVs) that have validated their applications for use with Oracle Linux and its virtualization capabilities. Certified applications on Oracle Linux are capable of running across various environments, including on-premises, Oracle Cloud Infrastructure, and other cloud services. Don't miss the opportunity to participate in the Oracle Tux Tech Talk webinar on July 28, where you will learn how to benchmark performance, explore the advantages of the Unbreakable Enterprise Kernel (UEK), and identify which workloads benefit from its enhancements. This session promises to equip you with valuable insights for optimizing your Linux applications.

Illumos is a Unix-based operating system that introduces cutting-edge features for downstream distributions, such as enhanced system debugging, a next-generation filesystem, advanced networking, and virtualization capabilities. It is developed collaboratively by volunteers along with companies that create products utilizing the software. Serving as a robust foundation for both traditional and cloud-native environments, illumos offers new users an excellent starting point with distributions like OmniOS and OpenIndiana. Users can opt to install it on virtual machines or directly on bare metal. To build illumos, an illumos-based operating system is required since cross-compilation is not an option. The software is freely accessible through its source repository. Hosting a variety of technologies, illumos boasts features like ZFS, DTrace, Zones, ctf, and FMA, among others. We take pride in delivering a stable, highly observable system that distinguishes itself technologically. With a rich engineering legacy, illumos can trace its origins back through Sun Microsystems to the early developments of UNIX and BSD, showcasing its historical significance in the evolution of operating systems. Its commitment to innovation continues to attract developers and users alike.

For over twenty years, we have been developing our operating system, consistently incorporating features that align with current market demands while ensuring that older applications remain functional. With our Application Binary Guarantee, users can seamlessly operate both the latest and legacy applications on contemporary infrastructure. Our advanced lifecycle management technologies enable you to execute a single command to update your entire cloud environment, covering everything from firmware to all virtualized spaces. A major player in the financial services sector experienced a remarkable 16-fold increase in efficiency by utilizing Oracle Solaris for managing its virtual machines, compared to a rival open-source solution. Additionally, the latest enhancements to the Oracle Solaris Observability tools empower users to troubleshoot both system and application issues in real time, providing immediate and historical data that enhances the ability to diagnose and resolve problems swiftly and effectively. This combination of features ensures that businesses can optimize their operations while remaining agile in an ever-evolving technological landscape.

Xinuos has recently launched UnixWare® 7.1.4, the most up-to-date version of its acclaimed UNIX® operating system. This robust and reliable system is designed to cater to your essential business applications while remaining cost-effective for all computing requirements. It is compatible with the latest industry-standard hardware and peripherals, incorporating enhanced performance, scalability, and reliability—hallmarks of the UnixWare brand. Additionally, the default configurations of the most sought-after editions have been optimized to enhance their value proposition. Both new installations and upgrades to UnixWare 7.1.4 will instantly reap the benefits of these improvements. A new, budget-friendly edition has also been introduced, specifically tailored for low-cost pilot projects, edge computing services, and business applications for smaller enterprises. This ensures that even small companies can access cutting-edge technology without breaking the bank.

IBM® z/OS® harnesses the robust capabilities of the IBM Z® platform to facilitate business transformation and foster innovation. It provides a stable and secure environment essential for enhancing performance in mission-critical tasks while preparing organizations for future challenges. This operating system is designed with high security and scalability, making it ideal for running essential applications. The advanced IBM® z16™ platform not only speeds up decision-making but also safeguards your operations against potential threats while adapting to hybrid cloud environments. With IBM z/OS V2.5, businesses can leverage cutting-edge development to enhance hybrid cloud and AI applications, alongside advanced technologies focused on security and resilience. Additionally, a continuous delivery model ensures that new features for z/OS are introduced quarterly without compromising stability, complexity, or costs, leading to swift application development and deployment in hybrid cloud settings. The system also offers a streamlined and modernized experience to simplify installation and management tasks, further enhancing operational efficiency. Organizations can thus embrace a transformative approach to their IT infrastructure, ensuring they remain competitive in a rapidly evolving digital landscape.

IBM z/VM is a sophisticated operating system that features a hypervisor and virtualization technology, designed to effectively manage guest servers like Linux, z/OS, and z/TPF virtual machines, as well as Red Hat OpenShift on IBM Z and LinuxONE systems. This platform is capable of operating hundreds or even thousands of guest servers on a single IBM Z or LinuxONE server with remarkable efficiency and adaptability. It accommodates various machine images and architectures, which streamlines the migration process, eases application transitions, and enables the consolidation of multiple systems onto one server. By excelling in resource sharing among virtual machines, IBM z/VM provides outstanding scalability, security, and efficiency, resulting in significant cost reductions and creating a solid foundation for cognitive computing. Its implementation supports on-premises cloud computing within a hybrid cloud framework, allowing organizations to efficiently scale and manage thousands of Linux and container workloads. Moreover, it aids in maintaining continuous availability through IBM's robust resiliency offerings, ensuring that businesses can rely on their infrastructure without interruption. This versatility makes IBM z/VM a critical asset for modern enterprises looking to optimize their IT environments.

For more than thirty years, AIX has been the trusted platform for our customers to operate their most essential applications. As we transition into a new age, AIX is poised to continue leading the way in innovation by integrating hybrid cloud and open source functionalities, which assist customers in creating and implementing modern applications within a secure and robust framework. It is crucial for enterprises to have infrastructure that offers security, exceptional availability, and flexibility to adapt to evolving business needs. AIX®️ on Power Systems not only provides these essential features but also ensures the performance, dependability, and security required by mission-critical data. By utilizing an architecture that aligns with your on-premises setup, you can streamline and speed up the cloud deployment of your AIX applications. Furthermore, you can achieve zero downtime during maintenance planning, while continuously modernizing AIX with the latest updates and improvements. The AIX UNIX operating system is firmly committed to maintaining a strong reputation for security, which has been established over many years, ensuring that your data remains protected and your operations uninterrupted. In addition, AIX's focus on innovation ensures that it remains relevant in an ever-evolving technological landscape.