What are Azure Cobalt Virtual Machines?
Azure Cobalt Virtual Machines run on Cobalt 100, Microsoft’s first fully in-house designed 64-bit Arm processor. The chip became generally available in 2024 alongside the first Cobalt VM series, marking Microsoft’s entry into the custom cloud silicon market, following AWS with Graviton and Google with Axion. Cobalt VMs are designed for Linux-based, horizontally scaling cloud-native workloads such as web and application servers, open-source databases, and caches.
Core Features
- Cobalt 100 is based on the Arm Neoverse N2 architecture, clocked at 3.4 GHz, with a full physical core per vCPU
- General-purpose series Dplsv6/Dpldsv6 (2 GiB RAM per vCPU) and Dpsv6/Dpdsv6 (4 GiB per vCPU)
- Memory-optimized series Epsv6/Epdsv6 (8 GiB RAM per vCPU) for memory-intensive workloads
- Broad guest OS support for Arm64 (including Ubuntu, RHEL, SUSE, Azure Linux, AlmaLinux, Debian)
- Native support as AKS nodes for containerized workloads
Typical Use Cases
Cost-optimized general-purpose workloads: Web servers, API backends, and microservices whose software is available as Arm64 or multi-arch builds.
Containerized applications on AKS: Kubernetes natively supports Arm64 nodes; multi-arch container images are standard today, allowing Cobalt nodes to integrate well into existing AKS clusters.
Scalable microservices and caches: Horizontally scaling, largely stateless services benefit particularly from the price-performance of the Cobalt platform.
Benefits
- Improved price-performance over the previous Arm VM generation on Azure, according to Microsoft
- Deep integration with Azure network and storage infrastructure
- Full support as AKS nodes for cloud-native architectures
- Choice between general-purpose and memory-optimized series depending on workload
Arm64 in the Cloud: Challenges and Opportunities
Using Arm64 VMs requires attention to software compatibility. Modern languages like Java, Python, Go, Rust, and Node.js support Arm64 without restrictions. Container images must be available as Arm64 or multi-arch images. Older proprietary software or statically compiled x86 binaries cannot run on Arm64. For most cloud-native applications built on open-source stacks, however, migration to Cobalt VMs is straightforward and offers noticeable cost and performance benefits, particularly for large AKS clusters and web-tier deployments.
Integration with innFactory
As a Microsoft Solutions Partner, innFactory supports you in evaluating and migrating to Azure Cobalt Virtual Machines: compatibility assessment, Arm64 build pipelines, AKS node pool configuration, and cost optimization.
Typical Use Cases
Frequently Asked Questions
What is the Cobalt 100 processor?
Cobalt 100 is Microsoft's first fully in-house designed 64-bit Arm processor, based on the Arm Neoverse N2 architecture and clocked at 3.4 GHz. Each vCPU gets a full physical core. Microsoft follows AWS (Graviton) and Google (Axion) into the custom cloud silicon market.
Which VM series use Cobalt 100?
The general-purpose series Dplsv6/Dpldsv6 (2 GiB RAM per vCPU) and Dpsv6/Dpdsv6 (4 GiB per vCPU), as well as the memory-optimized series Epsv6/Epdsv6 (8 GiB per vCPU), are based on Cobalt 100. Variants with 'd' in the name also include local temporary disk.
Are all Linux applications compatible with Arm64?
Most modern Linux applications natively support Arm64 or via multi-arch container images. Some older or proprietary software may require recompilation. Container workloads on AKS benefit particularly, since Kubernetes fully supports Arm64 nodes.
How do Cobalt VMs compare to AWS Graviton?
Both processor families pursue the same goal: better price-performance than x86 for cloud-native workloads. AWS Graviton has been on the market longer and has broader regional availability. Cobalt 100 is tailored specifically to the Azure stack and deeply integrated with Microsoft's network and storage infrastructure.
Note: All product information on this page has been compiled with care, but is provided without guarantee and may be outdated or incomplete. Cloud services evolve rapidly — features, pricing, SLAs, and availability change frequently. Authoritative and up-to-date information can only be found on the official product page of Azure (official documentation). This page does not represent an offer by Azure.
