What Is Metal-As-A-Service (MAAS)?

Metal as a Service (MaaS) is an open-source provisioning system that turns bare metal servers into cloud-like resources.

What Is Metal as a Service?

Metal as a Service is an open-source platform designed to simplify the management and deployment of physical servers by bringing cloud-like functionality to bare metal infrastructure. It provides a centralized system that discovers, commissions, and provisions physical machines, making them available for use in much the same way virtual machines are managed in a cloud environment.

Through automated workflows, MaaS handles tasks such as operating system installation, network configuration, power management, and integration with higher-level orchestration tools. By abstracting the complexity of managing individual servers, it enables administrators and developers to scale and repurpose hardware resources quickly, supporting environments that require direct access to physical machines, such as private clouds, container platforms, high-performance computing, and large-scale data centers.

Metal as a Service Architecture

Metal as a Service architecture is built around a set of core services and components that work together to discover, provision, and manage physical machines as if they were cloud instances. At the highest level, it follows a client–server model, where the MaaS controller manages the overall infrastructure, while agents and services on physical machines handle communication and execution.

The MaaS controller is the central component of the architecture. It includes the region controller and the rack controller, which together provide inventory management, networking, and power control.

The region controller is responsible for the API, web interface, and database, acting as the control plane for users and orchestration tools. The rack controller runs within the data center racks and communicates directly with the hardware, handling DHCP, TFTP, PXE booting, IP address assignment, and power management.

This layered approach ensures that machines can be discovered, booted, and imaged without manual intervention.

When new servers are connected, MaaS uses PXE boot and IPMI or similar interfaces to automatically discover the machines. It then commissions them by gathering hardware information, running diagnostics, and ensuring they are ready for deployment. Once commissioned, servers can be provisioned with different operating systems, kernel parameters, or configurations based on user needs.

MaaS integrates tightly with orchestration frameworks such as Juju, Kubernetes, and OpenStack, allowing hardware resources to be consumed programmatically in large-scale environments.

Metal as a Service Key Features

MaaS offers a broad set of capabilities that simplify and modernize bare metal management. Instead of manually configuring servers, administrators can rely on automated processes, scalable architecture, and integrations that align with cloud-native operations. Key features include:

• Automated hardware onboarding. New servers are automatically discovered and inventoried, eliminating manual tracking and reducing administrative overhead.
• Health assurance and validation. MaaS ensures servers meet reliability standards by running diagnostic checks and performance benchmarks before they are put into production.
• Flexible provisioning. It supports multiple Linux distributions, Windows, and custom images, enabling tailored deployments for diverse workloads and use cases.
• Integrated network and power control. With built-in support for DHCP, DNS, IPMI, and Redfish, MaaS allows network administrators to remotely manage connectivity and system power states without needing on-site access.
• Dynamic resource management. Physical servers are treated as a shared pool of compute capacity, making it easy to allocate, reclaim, and repurpose hardware as business needs evolve.
• Ecosystem compatibility. MaaS integrates with orchestration platforms like Kubernetes, Juju, and OpenStack, extending its usefulness in hybrid cloud and high-performance computing environments.
• Accessible management interfaces. A REST API and web-based dashboard provide both programmatic control and intuitive visualization for efficient day-to-day operations.
• Enterprise scalability. With region and rack controllers, MaaS can coordinate resources across thousands of machines and multiple data center locations.

How Does MaaS Work?

Metal as a Service (MaaS) transforms bare metal servers into dynamically provisioned, cloud-like resources. Instead of managing servers manually, MaaS automates discovery, commissioning, deployment, and integration, giving organizations the ability to treat physical machines with the same flexibility as virtualized infrastructure.

The workflow can be broken down into the following stages:

• Server discovery. When new machines connect to the network, MaaS uses PXE booting and services like DHCP and TFTP to detect them and collect hardware details such as CPU, memory, storage, and network interfaces.
• Commissioning. Discovered servers undergo hardware tests and validation routines to confirm they are operational and ready for deployment.
• Resource pooling. Verified machines are placed into a resource pool, making them available for on-demand allocation.
• Operating system deployment. Administrators or automation tools provision Linux, Windows, or custom OS images directly onto the hardware, preparing servers for specific workloads.
• Power management. Integrated through IPMI, Redfish, or vendor-specific APIs, enabling remote power cycling, rebooting, and shutdown.
• Infrastructure coordination. Region and rack controllers manage network assignments, DNS, and storage configurations for seamless integration across racks and data centers.
• Interfaces and integrations. MaaS provides both a REST API and web UI for management, and integrates with orchestration frameworks such as Juju, Kubernetes, and OpenStack.
• Overall function. By bridging traditional hardware management with modern cloud-style provisioning, MaaS allows organizations to consume physical servers with the same agility as virtual resources.

Metal as a Service Example

An example of MaaS in action would be a company setting up a private cloud for data-intensive workloads. Instead of manually installing operating systems on hundreds of servers, the IT team deploys MaaS in their data center.

When new servers are added to the racks, MaaS automatically detects them via PXE boot and commissions them by running diagnostics and collecting hardware information. Once validated, these servers are placed into a resource pool, ready for use.

The team then provisions a set of machines with Ubuntu Server to act as a Kubernetes cluster for containerized applications, while another group of machines is provisioned with Windows Server to handle Active Directory and file services.

MaaS manages networking by assigning IP addresses, configuring DNS, and handling VLANs across racks. Power control is automated through IPMI and Redfish, allowing administrators to remotely reboot or shut down machines without touching the hardware.

When workloads change, the IT team can release some machines from Kubernetes and re-provision them for high-performance computing tasks, such as AI training or big data analytics.

What Is Metal as a Service Used For?

Metal as a Service is used to simplify and automate the provisioning of bare metal servers, making physical infrastructure as flexible and scalable as cloud resources. By bridging the gap between traditional hardware management and modern cloud-native practices, MaaS supports a wide range of use cases across IT operations, development, and high-performance environments. Here are its main uses:

• Private cloud deployment. Organizations use MaaS to build private clouds on top of bare metal infrastructure. It integrates with platforms like OpenStack, enabling users to deploy cloud environments with the same agility as public clouds while maintaining control over hardware resources.
• Kubernetes and container platforms. MaaS provisions physical machines that serve as nodes in Kubernetes or other container orchestration systems. This provides reliable performance for containerized workloads that need direct hardware access and avoids virtualization overhead.
• High-performance Computing (HPC). Scientific research, simulations, and AI training often require dedicated compute power. MaaS enables rapid provisioning of bare metal clusters optimized for performance-intensive tasks, such as genomics or climate modeling.
• DevOps and continuous integration/continuous deployment (CI/CD). Development teams use MaaS to provision and recycle test environments quickly. It allows bare metal hardware to be repurposed for new builds, testing, or staging environments without manual setup.
• Hybrid and multi-cloud infrastructure. Enterprises that combine public cloud services with on-premises resources use MaaS to manage their physical servers with cloud-like agility. This makes it easier to move workloads between on-premises data centers and external cloud providers.
• Edge computing. At distributed sites like branch offices, telco edge locations, or IoT hubs, MaaS helps provision and manage servers that need to run close to end users or devices. This ensures low latency while maintaining centralized control from the MAAS controller.

Pros and Cons of MaaS

Metal as a Service brings cloud-like automation to bare metal infrastructure, offering clear benefits but also some challenges. Understanding its pros and cons helps organizations decide whether MaaS is the right fit for their IT strategy, balancing flexibility, scalability, and control against complexity and operational requirements.

MaaS Pros

Metal as a Service offers several advantages for organizations that want to manage physical servers with the speed and efficiency of cloud resources. By automating provisioning and centralizing control, MaaS helps IT teams streamline infrastructure operations while maximizing hardware utilization. Here are the main pros of MaaS:

• Cloud-like agility for bare metal. MAAS turns physical servers into on-demand resources, allowing them to be provisioned, re-imaged, or repurposed quickly. This reduces the manual work traditionally required for hardware management.
• Efficient resource utilization. By pooling servers and assigning them as needed, MaaS ensures hardware is used more effectively. Idle machines can be reallocated to different workloads, reducing waste and improving ROI on infrastructure investments.
• Wide OS and image support. MaaS supports deploying multiple operating systems, including Linux distributions, Windows, and custom images, on the same infrastructure, giving flexibility for diverse workloads.
• Integrated networking and power control. With built-in DHCP, DNS, VLAN management, and integration with IPMI/Redfish for power management, MAAS simplifies complex data center operations and reduces the need for separate management tools.
• Scalability across data centers. Its region and rack controller architecture allows thousands of machines across multiple racks or sites to be managed centrally, making it suitable for both mid-sized deployments and large-scale environments.
• Automation and API integration. Through its RESTful API, CLI, and web interface, MaaS integrates with orchestration frameworks like Juju, Kubernetes, and OpenStack. This supports automated workflows and enables hybrid or cloud-native environments.

MaaS Cons

While Metal as a Service offers powerful automation and flexibility for managing bare metal infrastructure, it also comes with challenges that organizations need to evaluate before adoption. These drawbacks often relate to complexity, operational overhead, and the suitability of MaaS for specific environments:

• Complex initial setup. Deploying MaaS requires configuring region and rack controllers, networking services, and integration with power management tools. This setup can be complex for teams unfamiliar with PXE booting, IPMI, or data center networking.
• Steep learning curve. Administrators need to understand not only MaaS itself but also the underlying technologies it relies on, such as DHCP, DNS, and baseboard management controller (BMC) interfaces. This can slow adoption, especially in smaller teams without deep infrastructure expertise.
• Limited support for non-standard hardware. While MaaS supports a wide range of hardware, unusual or proprietary systems may not integrate smoothly. This can lead to additional manual configuration or reduced automation benefits.
• Operational overhead compared to virtualization. Unlike virtualization, which allows easy creation and deletion of VMs, bare metal provisioning takes longer and consumes more resources. Repurposing machines in MaaS is faster than manual processes but slower than cloud-native virtualized alternatives.
• Resource intensity. Running MaaS effectively in large-scale environments requires dedicated controllers and careful planning of networking and power management infrastructure, which can add operational overhead.
• Not always cost-effective for small deployments. For organizations managing only a handful of servers, the effort required to set up and maintain MaaS may outweigh its benefits, making it more suitable for medium-to-large scale operations.

Metal-as-a-Service FAQ

Here are the answers to the most commonly asked questions about Metal-as-a-Service.

What Is the Difference Between SaaS and MaaS?

Here’s a clear side-by-side comparison of Software as a Service (SaaS) and Metal as a Service (MAAS):

Is MaaS Open Source?

Yes, Metal as a Service is open source. It is developed and maintained by Canonical, the company behind Ubuntu, and released under the GNU Affero General Public License (AGPL). This means organizations can freely download, use, and modify MaaS to fit their infrastructure needs.

In practice, MaaS is offered in two ways:

• Community Edition – the open-source version available at no cost, supported by the community.
• Enterprise Support – Canonical provides commercial support and integration services for organizations that require production-grade reliability, professional assistance, and long-term maintenance.

This dual model makes MAAS accessible for experimentation and smaller projects while also being suitable for enterprise environments that demand professional support.

What Is the Future of Metal as a Service?

The future of MaaS lies in extending its role as a bridge between physical infrastructure and cloud-native operations. As organizations increasingly adopt hybrid and multi-cloud strategies, demand is growing for tools that offer the agility of cloud platforms while maintaining control over on-premises hardware. MaaS is positioned to meet this need by evolving into a foundational layer for managing bare metal servers at scale.

One direction for MaaS is deeper integration with container orchestration and edge computing. With workloads shifting toward Kubernetes and distributed environments, MaaS will likely expand its automation capabilities for edge sites, telco infrastructure, and AI/ML clusters that require low latency and dedicated hardware. Enhanced support for heterogeneous architectures, including ARM and GPU-based systems, is also expected, enabling MaaS to serve specialized workloads in high-performance computing, machine learning, and data-intensive analytics.

Another future trend is tighter alignment with infrastructure as code practices. As DevOps and GitOps approaches become more widespread, MaaS will continue strengthening its APIs, Terraform providers, and automation hooks, allowing bare metal provisioning to be fully integrated into modern CI/CD pipelines.

Additionally, sustainability pressures may push MaaS toward offering smarter energy and lifecycle management features, helping organizations optimize power usage and hardware efficiency in large-scale data centers.