Introduction to HashiCorp Nomad: A Beginner’s Guide

For Kubernetes enthusiasts seeking new perspectives on container orchestration, HashiCorp Nomad presents an intriguing alternative. While Kubernetes has become the de facto standard for container management, Nomad offers a different approach, providing simplicity, flexibility, and efficiency for diverse workloads. 

Exploring Nomad may seem like a departure from the familiar Kubernetes ecosystem. Still, it offers a unique approach to application deployment and management that warrants exploration. 

Understanding HashiCorp Nomad

Nomad, developed by HashiCorp, is an open-source scheduler and orchestrator designed to deploy and manage applications across a range of infrastructure platforms, including: virtual machines, bare metal servers, and public cloud providers. 

Unlike Kubernetes, which is primarily focused on managing containerized workloads, Nomad takes a broader approach, supporting various types of workloads, including Docker containers, VMs, and standalone binaries.

Nomad follows the principles of simplicity and flexibility, offering a minimalist approach to container orchestration without compromising on functionality. Unlike Kubernetes, Nomad focuses on ease of use and operational simplicity, making it an ideal choice for organizations looking to streamline their container deployments. 

Key Features of HashiCorp Nomad

Simplicity: Nomad aims to provide a simple and intuitive experience for deploying and managing applications. Its lightweight footprint and straightforward configuration make it easy to get started with Nomad, even for users with limited experience in container orchestration.

Flexibility: Unlike some other orchestration platforms, Nomad is designed to support a wide range of workloads, including containerized applications, virtual machines, and standalone binaries. This flexibility enables organizations to adopt Nomad without being constrained by specific application architectures. 

Scalability: Nomad is designed to scale efficiently, allowing organizations to manage clusters of any size. Its distributed architecture and efficient scheduling algorithms ensure that applications are deployed and scaled according to resource requirements and constraints.

Integration: Nomad integrates seamlessly with other HashiCorp tools such as Consul and Vault, providing additional capabilities for service discovery, networking, and secrets management. These integrations enable organizations to build comprehensive solutions for deploying and managing applications in production environments.

Auto-Scaling: Nomad offers built-in auto-scaling capabilities, allowing applications to scale dynamically based on predefined metrics or custom triggers. This ensures optimal resource utilization and responsiveness to changing workload demands without manual intervention.

Multi-Cloud Support: Nomad is cloud-agnostic and supports deployment across multiple cloud providers and on-premises environments. This flexibility enables organizations to adopt a hybrid or multi-cloud strategy and avoid vendor lock-in while benefiting from the scalability and reliability of cloud services.

Architecture

Nomad has a single binary configured as the client as well as the server. We need to change the configuration accordingly. Let’s look into the architecture.

Nomad employs a client-server model. Nomad clients run on nodes and execute tasks, while Nomad servers manage job scheduling and cluster state. Jobs are defined in job files, specifying tasks, constraints, and resource requirements. 

The Nomad scheduler optimally places tasks based on available resources. Consul and Vault integration provides service discovery and secret management. Nomad clusters can scale horizontally for increased capacity and fault tolerance, ensuring reliable application deployment and management.

And one more advantage that I like is Nomad UI

Nomad UI serves as a web-based interface for managing Nomad clusters, offering job management, node overview, allocation details, configuration visualization, and event monitoring functionalities. It enhances visibility into cluster states, simplifies job management, and facilitates resource monitoring. Nomad UI is particularly useful for users who prefer graphical interfaces, and provides an intuitive means of interacting with Nomad clusters. 

The topology of Nomad UI typically involves frontend and backend components communicating with the Nomad cluster’s HTTP API. It can be deployed alongside Nomad servers or as a separate service, accessible via web browsers. 

The frontend manages the user interface, while the backend interacts with Nomad’s API to retrieve data and execute actions. Nomad UI’s architecture enables seamless communication with Nomad clusters, enhancing user experience and facilitating efficient cluster management and monitoring.

Getting Started with Nomad

Installation: Nomad can be installed easily using precompiled binaries, package managers, or containerized versions available on Docker Hub. It supports various operating systems, including Linux, macOS, and Windows.

Configuration: Nomad’s configuration consists of defining the cluster topology, specifying resource constraints, configuring integrations with Consul for service discovery, and defining job specifications for application deployments.

Job Submission: To deploy applications on Nomad, operators define job specifications using HashiCorp Configuration Language (HCL) or JSON. Job specifications include details such as task definitions, resource requirements, task groups, and health checks.

An explanation of the Nomad Job Specification

Monitoring and Observability: Nomad integrates with various monitoring and observability tools such as Prometheus and Grafana, allowing operators to gain insights into cluster performance, resource utilization, and application health.

Nomad vs. Kubernetes: Understanding the Differences

While both Nomad and Kubernetes are popular choices for orchestrating containerized workloads, they differ in several key aspects:

Complexity

Nomad is known for its simplicity and ease of use, making it an attractive option for organizations with minimal container orchestration experience. In contrast, Kubernetes has a steeper learning curve and requires more expertise to configure and manage effectively.

Workload Support

Nomad is designed to support a broader range of workloads, including not only containers but also virtual machines and standalone executables. Kubernetes, on the other hand, is primarily focused on container orchestration and may require additional tools or plugins to manage non-containerized workloads.

Scalability

While both platforms are capable of scaling applications dynamically, Kubernetes is often favored for larger, more complex deployments due to its robust scaling mechanisms and extensive ecosystem of third-party tools and integrations.

Ecosystem and Community

Kubernetes boasts a large and active community of developers and contributors, resulting in a rich ecosystem of tools, plugins, and extensions. Nomad, while growing in popularity, may have a smaller ecosystem by comparison but offers a more streamlined and cohesive experience out of the box.

And one more topic that I think is very important:

Nomad Pack is a packaging solution designed to simplify the deployment of applications on HashiCorp Nomad clusters. It facilitates the encapsulation of Nomad job configurations, including task definitions, resource constraints, and deployment strategies, into reusable packages. Nomad Pack aims to streamline the process of deploying applications on Nomad clusters, promoting consistency and repeatability in deployments.

Regarding the readiness for use, it’s important to note that Nomad Pack may not be as mature or widely adopted as Helm Charts available in Artifact Hub for Kubernetes. While Nomad Pack simplifies packaging for Nomad deployments, the ecosystem and community support for Helm Charts in Kubernetes, including Artifact Hub, offer a vast array of pre-built charts and configurations that make them more ready to use by Kubernetes users. As Nomad Pack continues to evolve and gain traction, its readiness and adoption are expected to improve over time.

A more detailed explanation about Nomad vs. K8S

Use Cases and Workload Considerations

Nomad is well-suited for various use cases, including:

• Microservices Deployment: Ideal for deploying and scaling microservices.
• Multi-Cloud Deployments: Offers portability across multiple cloud providers.
• Edge Computing: Lightweight for efficient edge workload management.
• Stateful Workloads: Supports persistent storage and data-intensive apps.

We prefer Nomad over Kubernetes in scenarios requiring simplicity, diverse workload management, resource efficiency, seamless integration, predictable behavior, and rapid deployment, making it ideal for small teams, varied workloads, resource optimization, HashiCorp ecosystem integration, consistent operations, and agile development needs.

Community and Resources

Contribution and Collaboration Community Support

 Official Forums: HashiCorp Discuss

 Official Documentation: HashiCorp Nomad documentation

 GitHub Repository: HashiCorp Nomad GitHub repository

 Nomad Plugins Repository: Nomad Plugins GitHub repository

Conclusion

Nomad represents a compelling choice for organizations seeking a lightweight, flexible, and user-friendly solution for orchestrating workloads across diverse infrastructure environments. With its intuitive interface, broad workload support, and seamless integration with other HashiCorp tools, Nomad empowers teams to deploy and manage applications with ease, regardless of scale or complexity.

While Kubernetes remains the dominant force in container orchestration, Nomad’s unique features and approach make it a worthy contender, particularly for organizations prioritizing simplicity, flexibility, and ease of adoption.