Containers in VMs or on Bare Metal: There’s a Clear Choice

When containers first burst onto the technology scene, they sparked an intense debate that continues today: should containers run on virtual machines or directly on bare metal servers? A new white paper from IDC by Gary Chen, Research Director, cuts through the noise with insights that may surprise many in the industry.

The Data Tells the Story

IDC forecasts that 85% of containers will run in VMs by 2028, continuing a trend that’s already dominant in today’s data centers. This isn’t just speculation – it’s based on how the world’s largest container deployments actually operate in production environments.

Look no further than the public cloud providers themselves. Despite having access to unlimited bare metal resources and no licensing costs to worry about, cloud giants consistently run containers in VMs. Why? Because the combination delivers what modern infrastructure demands: security, flexibility, scalability, and operational efficiency.

Why VMs Win for Most Workloads

The case for running containers in VMs comes down to several critical advantages. First and foremost is security. While containers provide good logical isolation, they weren’t designed to separate multiple tenants with the fortress-like boundaries offered by VMs. 

The ability to provide the agile, responsive infrastructure that modern Kubernetes clusters need is another. Virtual machines can be provisioned, reconfigured, and migrated in seconds. Bare metal nodes, by contrast, are locked to physical server configurations and constrained by slower hardware operations.

Operational realities must also be considered. Running containers on bare metal can introduce challenges like larger failure blast radiuses, difficulty managing enormous nodes with thousands of containers, suboptimal resource utilization, and less flexible cluster scaling. Most enterprise teams today would face significant reskilling and retooling costs to manage containers on bare metal at scale. In contrast, they have decades of experience with virtualization tools and processes.

The Modern Platform Approach

Platforms such as VMware Cloud Foundation (VCF) exemplify the future direction: unified infrastructure that seamlessly manages both VMs and containers together. This convergence makes particular sense for the mixed-mode applications common in enterprises today.

The bottom line? VMs and containers aren’t competitors – they’re complementary technologies operating at different stack levels. For the vast majority of enterprise use cases, the combination of containers running in VMs delivers the security, agility, and operational benefits that modern infrastructure demands. 

Read the IDC report to learn more about why containers run best in VMs, and check out this companion report from IDC to find out why it make sense to utilize a single platform such as VCF to deploy and manage both.