What is OpenVMS Operating System?

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    OpenVMS, short for Open Virtual Memory System, is a highly reliable and secure multi-user operating system initially developed by Digital Equipment Corporation (DEC) and later acquired by Compaq and then HP (Hewlett-Packard). Known for its robustness and scalability, it features strong process isolation, clustering capabilities, and comprehensive security measures, making it ideal for mission-critical environments.

    OpenVMS has a rich history dating back to the 1970s. However, HP later discontinued its support for OpenVMS for some hardware, so in response to that, VMS Software, Inc. (VSI) was formed and acquired the rights to develop, distribute, and support it. The OpenVMS VSI refers to the versions created by VSI and includes patches, updates, and new releases.

    While the VAX and Alpha hardware on which it typically ran is no longer manufactured, the OpenVMS operating system has withstood the test of time, and the critical applications running on it are still at the core of many business operations.

    What is OpenVMS?

    OpenVMS is a multiprocessing operating system for multiusers designed for batch processing, time-sharing, and a collective transaction ecosystem. Initially created by DEC for their VAX servers, it has been used for other platforms, such as Itanium, Alpha, and x86 servers.

    Did you know? Around half a million VMS systems operated worldwide between the 1990s and 2000s. Due to its high availability using clustering, these OS ensures that its application and data are accessible even during system failures and maintenance, with reported uptimes of up to 17 years.

    Key Features of OpenVMS

    OpenVMS has some notable key features that have made it popular in several industrial sectors. Some of them are:

    Process Isolation

    The intense process isolation ensures that errors during a process do not affect others and contribute to system stability.


    OpenVMS provides clustering support, which allows a wide range of systems to work collectively as a single system, thus providing options for high availability and fault tolerance.

    Robust Security

    OpenVMS offers robust security infrastructure, which includes authentication mechanisms, access controls, and auditing capabilities.

    File System

    This feature offers file-level security, versioning, and assistance for large files.


    System-wide health monitoring, mirroring of the system, error detection, and correction prevent system failures and ensure business continuity, making it highly reliable.


    It is a highly scalable operating system that supports large-scale deployments and efficiently handles growing workloads without compromising performance and stability.

    Networking Capabilities

    OpenVMS provides comprehensive networking capabilities, supporting various network protocols and communication standards.

    Compatibility and Support for Legacy Systems

    OpenVMS is backward compatible with previous versions of its OS while supporting a wide range of hardware platforms, including legacy applications. It ensures seamless migrations and integration with other software, which is highly demanded by various businesses.

    Is an Upgraded Version of OpenVMS Necessary?

    When businesses emulate their legacy hardware with Stromasys, we’re often asked whether an upgraded version of OpenVMS is necessary. Based on the VAX or AlphaServers to be virtualized, minimum versions of the OpenVMS Operating System (OS) are required, but the majority of businesses do not need to upgrade.

    Here’s why:

    With Charon, no changes are required to your OpenVMS operating system

    The most obvious benefit of using OpenVMS is that the legacy system continues functioning as it always has. In many implementations, the end users were entirely unaware that changes had occurred, and the application performed better. The end user feels no change in the OpenVMS OS except for increased efficient performance, such as a report will now be finished significantly faster due to the system that it would have been on the previous hardware platform.

    OpenVMS is entirely compatible with the original DEC system with Charon emulation solutions

    A second benefit is that the Charon VAX and Alpha emulator translation is bit-for-bit compatible with original DEC systems, including floating point precision.

    Stromasys uses Digital Equipment Corp.- developed tools to ensure Charon is 100% compatible with the original hardware, including MDM (MicroVAX Diagnostic Monitor), UETP (User Environment Test Package, part of VMS), and AXE (DEC’s VAX and Alpha CPU architecture verification tool).

    With Charon emulation no re-certification is required

    Another benefit to our legacy hardware emulation solutions is that no recertification is required because nothing above the hardware level is modified, including OpenVMS.

    For many verticals operating under heavy regulations or compliance standards, changes to the OpenVMS OS or application would require the business to undergo a lengthy and exhaustive recertification process to validate the system. Still, the Stromasys Charon solution makes that unnecessary.

    Charon Solutions mitigates risk by exchanging the aging hardware for a more modern, reliable alternative while providing a straightforward and low-hassle path to business continuity.

    Charon solution offers options for modernizing their IT infrastructure with OpenVMS Cloud

    Businesses are now also looking for OpenVMS cloud options as they offer several benefits like security, reliability, cost-efficiency, scalability, global reach, and modernization. It helps in leveraging the benefits of both cloud computing while preserving the strength of OpenVMS. It allows the businesses to refurnish their IT infrastructure and modernizes them as it reduces hardware costs.

    Also, by opting for the OpenVMS cloud option, businesses get the opportunity to modernize their legacy applications by integrating them with other cloud-computing applications and technologies. This helps them enhance their agility and facilitates seamless collaborations across different platforms while enabling digital transformation initiatives.

    Improve Operational Efficiencies with Charon

    With the virtualization of organization’s Alpha and VAX environments, ccompanies can experience enormous savings from decreased service and support costs, downtime, and SG&A. In addition, the new Open x86 servers are much more environmentally friendly, providing power and resource savings versus the VAX and Alphaservers.

    Stromasys Charon Solutions

    Our solution is a hardware emulation solution—we don’t change the applications, databases, or legacy OpenVMS operating system running on that hardware without any modifications or code recompiling.

    Charon software allows a modern Open x86 server to function the same way the legacy server always did. It means that it doesn’t matter what version of OpenVMS OS or other legacy OS you’re running.

    Stromasys offers both cloud-based as well as on-perm options. If you choose to transition with us to OpenVMS on cloud, you’ll have a range of cloud options to choose from, each with its own unique benefits. These include:

    • The Microsoft Azure Cloud
    • The AWS Cloud
    • The Google Cloud
    • The Oracle Cloud

    Stromasys offers a seamless transition to your aging legacy, like VAX, Alpha, and SPARC applications on the cloud. This approach enhances availability and reliability as there will be no interference from a multi-purpose OS. When you virtualize with us, nothing has to change. Your OpenVMS operating system will work the way it always has. The only difference is that you’ll be able to get rid of the aging hardware that’s slowing you down, which means reduced maintenance costs. This way, you can eliminate your existing legacy hardware and connect your office infrastructure to the cloud through a private network, which is more secure.

    Furthermore, transitioning with us ensures that your end users don’t feel any difference. And, if they do notice anything different in the OpenVMS operating system, it’s that processes seem to happen more quickly, and that less downtime is experienced. There is no learning curve, and no recertification is required.

    To discover more about Charon solutions and modernize your legacy systems while maintaining business continuity,Contact Us

    Frequently Asked Questions (FAQs)

    1.What is OpenVMS and what sets it apart from other operating systems?

    OpenVMS is a robust and secure operating system, and its unique features include clustering capabilities, advanced security mechanisms, and support for legacy applications.

    2.Is OpenVMS still relevant in today’s computing landscape?

    Yes, the OpenVMS operating system remains relevant, especially in finance, healthcare, and manufacturing industries, where uptime, security, and stability are paramount. Many organizations rely on OpenVMS to run critical applications and maintain legacy systems.

    3.Can OpenVMS applications be modernized or migrated to newer platforms?

    While OpenVMS itself doesn’t require modernization, its applications definitely need it. The various strategies include re-platforming, re-engineering, or using emulation and virtualization solutions to run them on contemporary hardware. Each approach depends on the specific requirements and constraints of the organization.

    4.What support options are available for OpenVMS users?

    OpenVMS users can access support services from various sources, including the official OpenVMS support organization, third-party vendors, user communities, and consulting firms specializing in OpenVMS.

    5. What is OpenVMS ISO?

    OpenVMS ISO is the ISO image file that contains the OpenVMS operating system files. These files are used to create an installation disc or a CD to install this OS directly into a virtual machine or a system.

    6.What is OpenVMS cloud?

    When the OpenVMS operating system is deployed and hosted on a cloud environment, it is defined as the OpenVMS cloud. This means running OpenVMS on a virtual environment provided by cloud service providers like AWS, Google Cloud Platform, or Microsoft Azure.

    7.What is OpenVMS for x86?

    OpenVMS for x86 is a version of the OpenVMS operating system tailored to function on the infrastructure. Although OpenVMS was initially designed for proprietary architectures like AlphaServers and VAX, this version enables it to seamlessly work on the modern and latest hardware platforms.