Single Node nomad and consul

deployment.hcl

job "hello-world" {
  datacenters = ["dc1"]
  namespace   = "default"
  type        = "service"

  group "redis" {
    # Specify number of replicas of redis needed.
    count = 1

    # Specify networking for the group, port allocs.
    network {
      # Bridge is an isolated network namespace created for this group.
      # Applications outside this mode don't have access to this namespace.
      mode = "bridge"
      port "redis-tcp" {
        # Map the port to task.
        to           = 6379
        host_network = "private"
      }
    }

    # If unhealthy, restart 3 times in 2 minutes with a delay of 15s between each restart.
    # If it still fails, it'll be marked as unhealthy and won't be restarted again.
    restart {
      attempts = 3
      interval = "2m"
      delay    = "15s"
      mode     = "fail"
    }

    # If alloc is failed, the group will be rescheduled with a preference to a node that
    # hasn't been used previously.
    reschedule {
      attempts       = 15
      interval       = "1h"
      delay          = "30s"
      delay_function = "exponential"
      max_delay      = "120s"
      unlimited      = false
    }

    # Register a service with Consul. 
    service {
      name = "redis"
      port = "6379"
      tags = ["cache", "redis"]

      # Specify a health check. Since Consul Connect cannot do a TCP check
      # we need to add a script check here. This check is executed from the task
      # namespace itself and each check takes about a full second to come up and tear
      # down, so be mindful when keeping timeouts.
      check {
        name     = "ping-pong"
        type     = "script"
        command  = "redis-cli"
        args     = ["ping"]
        task     = "redis"
        interval = "15s"
        timeout  = "7s"
      }

      # Expose an envoy proxy.
      # No upstream is defined here, this is just for Envoy proxy in app to communicate with Envoy proxy in redis.
      connect {
        sidecar_service {
        }
      }
    }

    task "redis" {
      driver = "docker"

      config {
        image = "redis:6"
        ports = ["redis-tcp"]
      }

      resources {
        cores  = 1
        memory = 256
      }
    }
  }

  group "app" {
    network {
      port "http" {
        to = 8080
      }
      mode = "bridge"
    }


    service {
      name = "app-proxy-sidecar"
      port = "3000"

      check {
        name     = "check healthcheck endpoint"
        type     = "http"
        port     = "http"
        path     = "/healthz"
        interval = "30s"
        timeout  = "7s"
      }

      # Expose an envoy proxy. Define upstream as redis.
      connect {
        sidecar_service {
          proxy {
            config {
              protocol = "tcp"
            }
            upstreams {
              destination_name = "redis"
              local_bind_port  = 6379
            }
          }
        }
      }
    }

    restart {
      attempts = 3
      interval = "2m"
      delay    = "15s"
      mode     = "fail"
    }

    task "app" {
      driver = "docker"
      env {
        DEMO_REDIS_ADDR = "localhost:6379"
      }

      config {
        image = "registry.service.consul:32000/hello-app:1.1.0"
        ports = ["http"]

        // command = "sleep"
        // args = [
        //   "infinity"
        // ]
      }

      resources {
        cores  = 1
        memory = 512
      }
    }
  }
}

instructions.md

• Get Nomad from here.

• Install CNI plugin from and ensure it's available inside /opt/cni/bin. Follow docs for more details.

• Run the local agent:

sudo nomad agent -config=nomad.hcl

• Check node status

nomad node status

• Run example deployment

nomad init
nomad run example.nomad

nomad.hcl

datacenter = "dc1"
data_dir = "/opt/nomad/data"

log_level = "DEBUG"

bind_addr = "0.0.0.0"

server {
  enabled          = true
  bootstrap_expect = 1
}

client {
  enabled = true
 
  meta {
      env   = "dev"
      stack = "localtests"
  }
}


plugin "docker" {
  config {
    allow_privileged = true
    volumes {
      enabled = true
    }
    extra_labels = ["job_name", "job_id", "task_group_name", "task_name", "namespace", "node_name", "node_id"]
  }
}