This is a demo of a much larger experience.

Nomad and Consul Integration Guide

Overview

This guide covers the basic integration between HashiCorp Nomad and Consul for service discovery and health checking.

Prerequisites

• Nomad installed and running
• Consul installed and running
• Both services accessible on your network

Configuration

1. Configure Nomad to Connect to Consul

Add the following to your Nomad configuration file (e.g., nomad.hcl):

consul {
  address = "127.0.0.1:8500"
  auto_advertise = true
  server_auto_join = true
  client_auto_join = true
}

2. Basic Job with Service Registration

Create a job file that registers a service with Consul:

job "example" {
  datacenters = ["dc1"]

  group "web" {
    count = 3

    task "nginx" {
      driver = "docker"

      config {
        image = "nginx:latest"
        port_map {
          http = 80
        }
      }

      resources {
        network {
          port "http" {}
        }
      }

      service {
        name = "nginx-web"
        port = "http"

        tags = [
          "web",
          "nginx"
        ]

        check {
          type     = "http"
          path     = "/"
          interval = "10s"
          timeout  = "2s"
        }
      }
    }
  }
}

3. Verify Integration

Check that services are registered in Consul:

consul catalog services

View service details:

consul catalog nodes -service=nginx-web

Key Features

• Automatic Service Registration: Nomad automatically registers services with Consul
• Health Checks: Define health checks that Consul monitors
• Service Discovery: Applications can discover services via Consul DNS or API
• Load Balancing: Use Consul for service mesh capabilities

Common Use Cases

1. Service Discovery: Applications query Consul to find service endpoints
2. Health Monitoring: Consul tracks service health and removes unhealthy instances
3. Dynamic Configuration: Use Consul KV store with Nomad templates

Troubleshooting

• Ensure Consul agent is running: consul members
• Check Nomad-Consul connection: nomad server members
• Verify service registration: consul catalog services
• Review Nomad logs for connection errors

Next Steps

• Explore Consul Connect for service mesh
• Implement Consul KV with Nomad templates
• Set up multi-datacenter configurations