How Does Nomad Work?

Video notes

Nomad is a scheduler also known as an orchestrator.

Nomad is an Orchestrator

What is an Orchestrator? - A program to coordinate and schedule complex computer system tasks across infrastructure. Workloads could be containers, VMs, raw executables, JAR files, and more.

• Orchestrators first became popular for large data analytics jobs that took too long to process if they weren't intelligently broken up and scheduled efficiently across an infrastructure

• HashiCorp Nomad is an orchestrator that provides an efficient way to manage those tasks

• Jobs don’t necessarily need to be complex. You can use Nomad as your one tool to schedule all jobs, all applications, and any task, regardless of complexity levels.

Nomad Uses Bin Packing

What is an Bin Packing? - A workload placement strategy that uses mathmatics to determine the most efficient way to "pack" workloads into your infrastructure resources.

What is Anti-Affinity? - A workload placement strategy that doesn't allow backup/redundant jobs to be on the same piece of infrastructure, where an outage could cause that job to become unavailable.

Cost Savings of Orchestration

• Save on resource utilization
• Save on reduced developer deployment time

What Can Nomad Run? Where Can It Run?

Well... anything... anywhere.

Multi-Cloud - Single or Multi-Cloud, Hybrid, or On-prem

Multi-OS - Window, Linux, ARM, etc.

Multi-Workload - Docker - Java - Qemu - Raw & Isolated Executables - Even more with extensible task drivers

Reference Architecture - Building a Nomad Cluster

• Nomad requires 3 or 5 servers in its “cluster”

• This provides a balance between availability and performance

• HashiCorp Consul Agents are present on each nod

• Can also support HashiCorp Vault for dynamic credentials out of box

Nomad Customer Case Study

• Infrastructure of 11K+ Nodes
• Managed by 4 SREs

Nomad User Experience

What is a Job? - A job is any task Nomad needs to run - Easy to learn - Written in HCL

Uses the model, Job > Group > Task - Each Group of tasks will run on the same host - Each Task is a unique action for Nomad to take

CI/CD - Job files can be written in HashiCorp Terraform, making CI/CD pipelining easy

Recap

Nomad is an Orchestration tool that has several advantages: - It's a single binary - Bin Packing algorithms - Simple job syntax - Can run any workload - Multi-Cloud, Multi-OS, Multi-Platform

To learn how to use Nomad, visit the Nomad Track on HashiCorp Learn. For case studies, check out our resources page.