We're flexible

IBM mainframes run operating systems including z/OS®, z/VM®, z/VSE®, Linux on IBM Z®, and z/TPF. In fact, it is common for multiple operating systems to run on a single mainframe. Each operating system is a sophisticated product with unique characteristics designed to make the best use of your mainframe investment.

Explore the mainframe operating systems


IBM z/OS is a widely-used mainframe operating system designed for a stable, secure and highly available environment. z/OS offers security to protect sensitive information and assets. With resiliency, scalability and speed, z/OS helps exceed availability and response time objectives for business applications.

Linux on Z

Open source Linux distributions run on IBM Z, benefitting from the mainframe’s security, IT efficiency, availability and performance. Linux on Z provides an enterprise platform for cloud and analytics. Coupled with virtualization, a single mainframe can run thousands of virtual Linux servers concurrently.


This leading hypervisor for critical workloads can run thousands of Linux on Z virtual machines on one mainframe and can host z/OS, z/VSE and z/TPF. IBM z/VM’s reliability, performance, system management, scalability and security offer a strong foundation for Linux applications.


IBM z/VSE is an easy to manage and widely-used IBM mainframe operating system for reliable and secure online transactions and batch workloads. It can be integrated into a hybrid IT environment with z/VSE Connectors and enhanced with new workloads in a colocated Linux on Z environment.


The z/Transaction Processing Facility (z/TPF) is a special-purpose mainframe operating system used to process high transaction volumes, such as credit card transactions and airline reservations. It handles near real-time transactions with the quality service of the IBM Z mainframe.

Hear from customers

The ability to run our legacy applications and our modern, specialist ones using both the IBM z/OS and Linux on Z is super convenient, and gives us a high degree of IT management flexibility.

Justin Randall, Technical Services Supervisor, NCFB

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