Siemens Healthineers

The mandate from leadership was clear: Migrate thousands of virtual machines (VMs) in just one year. The IT team knew such a shift could take three years and impact hundreds of internal users.

Siemens Healthineers, a global leader in medical imaging and diagnostics, ran a staggering 85% of its systems and workloads on VMs. This deep dependency underscored the complexity and scale of the task at hand, as the company aimed not only to meet its ambitious migration timeline but also to ensure a seamless transition without disrupting operations. This was no small feat.

For over 120 years, Siemens Healthineers has served healthcare providers worldwide, with its technology forming the backbone of modern medicine. Operating seven global data centers—80% powered by NetApp—the company maintains a cloud-first strategy without sacrificing its robust on-premises operations. Every technology decision is driven by a commitment to advancing healthcare and improving patient outcomes.

This migration presented a unique hurdle. “We were looking at thousands of VMs,” said David Häfner from MR Datentechnik, Siemens Healthineers’ infrastructure operations partner. “Every VM represents a critical application for some business unit. Any downtime hurts operations and could impact the delivery of diagnostic or imaging technology to patients.”

The goal wasn’t just about escaping rising licensing costs. It was about simplifying the IT ecosystem by consolidating onto Microsoft Azure for unified control and greater efficiency.

The problem? Traditional migration methods would mean roughly two hours of downtime per VM. With thousands of VMs—many with complex configurations dating back decades—the potential for disruption was massive. The team needed a solution that could reduce downtime to minutes, not hours.

The solution emerged from a powerful collaboration between Siemens Healthineers, NetApp, and MR Datentechnik. At the heart of the migration: the free NetApp^® Shift Toolkit and the unified storage architecture powered by NetApp ONTAP^® software.

“What really made a difference was NetApp’s agile approach,” said Kai Graf, Technology Lead for the VMware Forward project at Siemens Healthineers. “We worked closely with NetApp’s Niyaz “NiMo” Mohamed and his team. When we identified a need, we could get a script modified even before the official release. The team added features and created toggle buttons—all within days, sometimes the same week. This agile co-development approach was amazing.”

The Shift Toolkit uses NetApp FlexClone^® technology to perform migrations directly on the datastore, eliminating the time-consuming download-convert-upload cycle. Instead of copying terabytes of data, the Toolkit created instant clones and converted disk formats in place. The Toolkit reduced a process that typically took two hours per VM to just 15 minutes, regardless of VM size—an eightfold speed improvement.

The team could migrate five to six VMs in a single one-to-two-hour maintenance window, with actual downtime measured in minutes rather than hours. “With Shift, we saved enormous amounts of time on pre- and post-processing,” said Häfner. “Less than an hour of downtime per batch.”

But speed wasn’t the only advantage. The unified architecture of NetApp ONTAP meant Siemens Healthineers could reuse its existing storage infrastructure. The same NetApp systems that served NFS volumes to VMware ESXi could now serve SMB shares to Hyper-V clusters. Siemens Healthineers didn’t need to purchase new storage and didn't have to physically move any data. The investment protection was substantial.

“We could completely reuse what was already there,” said Graf. “Same storage, same capacity, same systems. It’s very beneficial. From a technical point of view, now it’s an SMB share in the Hyper-V cluster. Before, it was NFS in the ESXi cluster. That’s the only thing that changed.”

This approach proved invaluable not only for the migration but also for an ongoing data center relocation project running in parallel. Using NetApp MetroCluster^®, the team could move storage nodes to dispersed data centers while maintaining operations and running two massive infrastructure projects simultaneously.

The results exceeded expectations. The team accomplished what industry experts said would take three years in the first year—not just in technology enablement, but in actual production migrations. The non-disruptive migration allowed Siemens Healthineers to focus on its mission to advance patient care through innovative technology.

Speed and efficiency

• 8x faster migrations: The Toolkit reduced VM conversions from two hours to 15 minutes per VM
• Minimal downtime: Less than one hour per migration batch, with most VMs experiencing only minutes of disruption
• Thousands of VMs migrated: Across multiple global locations, including Germany and India

Investment protection

• Zero new storage purchases: The team fully reused existing NetApp infrastructure
• Multiprotocol flexibility: Seamless transition from NFS to SMB on the same storage platform
• Parallel projects enabled: Simultaneous data center relocation using MetroCluster technology

Operational excellence

The agile, collaborative approach made the difference when unexpected challenges arose. With every special configuration, every misconfiguration from decades past, and every unique Linux distribution, the team worked together to find solutions. “We had Ubuntu, we had SUSE, different distributions, different ages. Some workloads were decades old with long histories and complex configuration files,” said Graf. “But we came up with solutions very fast when we ran into errors. There were no showstoppers.”

Internal business units provided positive feedback about the migration process itself: planning, communication, and execution. While some missed familiar features, the team worked to replicate functionality where technology allowed, maintaining service quality throughout the transition.

The migration journey continues. With the German location as the blueprint, Siemens Healthineers teams in India, Slovakia, and the United States are now following the established pattern. Each location can leverage the lessons learned and the proven approach that made the initial deployment successful. This concerted effort underscores Siemens Healthineers’ commitment to empowering healthcare professionals and improving patient outcomes worldwide.

“We were the pilot, pioneering this approach,” Graf said. “Our Hyper-V design—how we connect the network, how we connect the storage—became the blueprint that others are following. Of course, there are differences from location to location, but we showed it could be done."

A data center relocation project is advancing in parallel, with plans to use MetroCluster to move infrastructure while maintaining uptime for critical healthcare applications. The team is also exploring NetApp Backup and Recovery for enhanced data protection and continues to expand its use of Cloud Volumes ONTAP for Azure for backups and storage tiering.

Looking ahead, the organization is beginning to explore use cases for machine learning and AI workloads on its infrastructure. The flexibility of the NetApp platform positions Siemens Healthineers to drive future innovation.

The relationship with NetApp continues to strengthen, built on a foundation of reliable technology, responsive support, and true partnership. As Graf said, “We were lucky that we had NetApp. Others without NetApp storage have had to build their own migration tools. We gained enormous speed for our migrations.”

That speed, flexibility, and partnership approach helped Siemens Healthineers complete an ambitious migration, showing what can be achieved when expert teams work together.