trying out nomad example

example.nomad

# There can only be a single job definition per file. This job is named
# "example" so it will create a job with the ID and Name "example".

# The "job" stanza is the top-most configuration option in the job
# specification. A job is a declarative specification of tasks that Nomad
# should run. Jobs have a globally unique name, one or many task groups, which
# are themselves collections of one or many tasks.
#
# For more information and examples on the "job" stanza, please see
# the online documentation at:
#
#     https://www.nomadproject.io/docs/job-specification/job.html
#
job "example" {
  # The "region" parameter specifies the region in which to execute the job. If
  # omitted, this inherits the default region name of "global". Note that this example job
  # is hard-coded to eu-west-1, so if you are running your example elsewhere, make
  # sure to update this setting, as well as the datacenters setting.
  region = "eu-west-2"

  # The "datacenters" parameter specifies the list of datacenters which should
  # be considered when placing this task. This must be provided. Note that this example job
  # is hard-coded to eu-west-1, so if you are running your example elsewhere, make
  # sure to update this setting, as well as the region setting.
  datacenters = ["eu-west-2b", "eu-west-2a", "eu-west-2c"]

  # The "type" parameter controls the type of job, which impacts the scheduler's
  # decision on placement. This configuration is optional and defaults to
  # "service". For a full list of job types and their differences, please see
  # the online documentation.
  #
  # For more information, please see the online documentation at:
  #
  #     https://www.nomadproject.io/docs/jobspec/schedulers.html
  #
  type = "batch"

  # The "constraint" stanza defines additional constraints for placing this job,
  # in addition to any resource or driver constraints. This stanza may be placed
  # at the "job", "group", or "task" level, and supports variable interpolation.
  #
  # For more information and examples on the "constraint" stanza, please see
  # the online documentation at:
  #
  #     https://www.nomadproject.io/docs/job-specification/constraint.html
  #
  # constraint {
  #   attribute = "${attr.kernel.name}"
  #   value     = "linux"
  # }

  # The "update" stanza specifies the job update strategy. The update strategy
  # is used to control things like rolling upgrades. If omitted, rolling
  # updates are disabled.
  #
  # For more information and examples on the "update" stanza, please see
  # the online documentation at:
  #
  #     https://www.nomadproject.io/docs/job-specification/update.html
  #
  # update {
  #  # The "stagger" parameter specifies to do rolling updates of this job every
  #  # 10 seconds.
  #  stagger = "10s"

  #  # The "max_parallel" parameter specifies the maximum number of updates to
  #  # perform in parallel. In this case, this specifies to update a single task
  #  # at a time.
  #  max_parallel = 1
  # }

  # The "group" stanza defines a series of tasks that should be co-located on
  # the same Nomad client. Any task within a group will be placed on the same
  # client.
  #
  # For more information and examples on the "group" stanza, please see
  # the online documentation at:
  #
  #     https://www.nomadproject.io/docs/job-specification/group.html
  #
  group "cache" {
    # The "count" parameter specifies the number of the task groups that should
    # be running under this group. This value must be non-negative and defaults
    # to 1.
    count = 1

    # The "restart" stanza configures a group's behavior on task failure. If
    # left unspecified, a default restart policy is used based on the job type.
    #
    # For more information and examples on the "restart" stanza, please see
    # the online documentation at:
    #
    #     https://www.nomadproject.io/docs/job-specification/restart.html
    #
    restart {
      # The number of attempts to run the job within the specified interval.
      attempts = 10
      interval = "5m"

      # The "delay" parameter specifies the duration to wait before restarting
      # a task after it has failed.
      delay = "25s"

     # The "mode" parameter controls what happens when a task has restarted
     # "attempts" times within the interval. "delay" mode delays the next
     # restart until the next interval. "fail" mode does not restart the task
     # if "attempts" has been hit within the interval.
      mode = "delay"
    }

    # The "ephemeral_disk" stanza instructs Nomad to utilize an ephemeral disk
    # instead of a hard disk requirement. Clients using this stanza should
    # not specify disk requirements in the resources stanza of the task. All
    # tasks in this group will share the same ephemeral disk.
    #
    # For more information and examples on the "ephemeral_disk" stanza, please
    # see the online documentation at:
    #
    #     https://www.nomadproject.io/docs/job-specification/ephemeral_disk.html
    #
    ephemeral_disk {
      # When sticky is true and the task group is updated, the scheduler
      # will prefer to place the updated allocation on the same node and
      # will migrate the data. This is useful for tasks that store data
      # that should persist across allocation updates.
      # sticky = true
      # 
      # Setting migrate to true results in the allocation directory of a
      # sticky allocation directory to be migrated.
      # migrate = true

      # The "size" parameter specifies the size in MB of shared ephemeral disk
      # between tasks in the group.
      size = 300
    }

    # The "task" stanza creates an individual unit of work, such as a Docker
    # container, web application, or batch processing.
    #
    # For more information and examples on the "task" stanza, please see
    # the online documentation at:
    #
    #     https://www.nomadproject.io/docs/job-specification/task.html
    #
    task "hello_world" {
      # The "driver" parameter specifies the task driver that should be used to
      # run the task.
      driver = "exec"

      # The "config" stanza specifies the driver configuration, which is passed
      # directly to the driver to start the task. The details of configurations
      # are specific to each driver, so please see specific driver
      # documentation for more information.
      config {
        command = "/bin/echo"
        args    = ["Hello, World!"]
      }

      # The "artifact" stanza instructs Nomad to download an artifact from a
      # remote source prior to starting the task. This provides a convenient
      # mechanism for downloading configuration files or data needed to run the
      # task. It is possible to specify the "artifact" stanza multiple times to
      # download multiple artifacts.
      #
      # For more information and examples on the "artifact" stanza, please see
      # the online documentation at:
      #
      #     https://www.nomadproject.io/docs/job-specification/artifact.html
      #
      # artifact {
      #   source = "http://foo.com/artifact.tar.gz"
      #   options {
      #     checksum = "md5:c4aa853ad2215426eb7d70a21922e794"
      #   }
      # }

      # The "logs" stana instructs the Nomad client on how many log files and
      # the maximum size of those logs files to retain. Logging is enabled by
      # default, but the "logs" stanza allows for finer-grained control over
      # the log rotation and storage configuration.
      #
      # For more information and examples on the "logs" stanza, please see
      # the online documentation at:
      #
      #     https://www.nomadproject.io/docs/job-specification/logs.html
      #
      # logs {
      #   max_files     = 10
      #   max_file_size = 15
      # }

      # The "resources" stanza describes the requirements a task needs to
      # execute. Resource requirements include memory, network, cpu, and more.
      # This ensures the task will execute on a machine that contains enough
      # resource capacity.
      #
      # For more information and examples on the "resources" stanza, please see
      # the online documentation at:
      #
      #     https://www.nomadproject.io/docs/job-specification/resources.html
      #
      resources {
        cpu    = 500 # 500 MHz
        memory = 256 # 256MB
        network {
          mbits = 10
          port "db" {}
        }
      }

      # The "service" stanza instructs Nomad to register this task as a service
      # in the service discovery engine, which is currently Consul. This will
      # make the service addressable after Nomad has placed it on a host and
      # port.
      #
      # For more information and examples on the "service" stanza, please see
      # the online documentation at:
      #
      #     https://www.nomadproject.io/docs/job-specification/service.html
      #
      # service {
      #   name = "global-redis-check"
      #   tags = ["global", "cache"]
      #  port = "db"
      #   check {
      #     name     = "alive"
      #     type     = "tcp"
      #     interval = "10s"
      #     timeout  = "2s"
      #   }
      #  }

      # The "template" stanza instructs Nomad to manage a template, such as
      # a configuration file or script. This template can optionally pull data
      # from Consul or Vault to populate runtime configuration data.
      #
      # For more information and examples on the "template" stanza, please see
      # the online documentation at:
      #
      #     https://www.nomadproject.io/docs/job-specification/template.html
      #
      # template {
      #   data          = "---\nkey: {{ key \"service/my-key\" }}"
      #   destination   = "local/file.yml"
      #   change_mode   = "signal"
      #   change_signal = "SIGHUP"
      # }

      # The "vault" stanza instructs the Nomad client to acquire a token from
      # a HashiCorp Vault server. The Nomad servers must be configured and
      # authorized to communicate with Vault. By default, Nomad will inject
      # The token into the job via an environment variable and make the token
      # available to the "template" stanza. The Nomad client handles the renewal
      # and revocation of the Vault token.
      #
      # For more information and examples on the "vault" stanza, please see
      # the online documentation at:
      #
      #     https://www.nomadproject.io/docs/job-specification/vault.html
      #
      # vault {
      #   policies      = ["cdn", "frontend"]
      #   change_mode   = "signal"
      #   change_signal = "SIGHUP"
      # }

      # Controls the timeout between signalling a task it will be killed
      # and killing the task. If not set a default is used.
      # kill_timeout = "20s"
    }
  }
}

nomad-consul.json

{
  "min_packer_version": "0.12.0",
  "variables": {
    "aws_region": "eu-west-2",
    "nomad_version": "0.7.1",
    "consul_module_version": "v0.3.1",
    "consul_version": "1.0.3"
  },
  "builders": [
    {
      "ami_name": "nomad-consul-amazon-linux-{{isotime | clean_ami_name}}",
      "ami_description": "An Amazon Linux AMI that has Nomad and Consul installed.",
      "instance_type": "t2.micro",
      "name": "amazon-linux-ami",
      "region": "{{user `aws_region`}}",
      "type": "amazon-ebs",
      "source_ami_filter": {
        "filters": {
          "virtualization-type": "hvm",
          "architecture": "x86_64",
          "name": "*amzn-ami-hvm-*",
          "block-device-mapping.volume-type": "gp2",
          "root-device-type": "ebs"
        },
        "owners": [
          "amazon"
        ],
        "most_recent": true
      },
      "ssh_username": "ec2-user"
    }
  ],
  "provisioners": [
    {
      "type": "shell",
      "inline": [
        "sudo yum install -y git"
      ],
      "only": [
        "amazon-linux-ami"
      ]
    },
    {
      "type": "shell",
      "inline": [
	"git clone --branch v0.4.2 https://github.com/hashicorp/terraform-aws-nomad.git /tmp/terraform-aws-nomad",
        "/tmp/terraform-aws-nomad/modules/install-nomad/install-nomad --version {{user `nomad_version`}}"
      ],
      "pause_before": "30s"
    },
      {
      "type": "shell",
      "environment_vars": [
        "NOMAD_VERSION={{user `nomad_version`}}",
        "CONSUL_VERSION={{user `consul_version`}}",
        "CONSUL_MODULE_VERSION={{user `consul_module_version`}}"
      ],
      "script": "{{template_dir}}/setup_nomad_consul.sh"
    }
  ]
}

output.txt

dans-mbp:terraform-aws-nomad dan$ nomad run -address=http://35.176.91.104:4646 examples/nomad-examples-helper/example.nomad 
==> Monitoring evaluation "814a173d"
    Evaluation triggered by job "example"
    Evaluation status changed: "pending" -> "complete"
==> Evaluation "814a173d" finished with status "complete" but failed to place all allocations:
    Task Group "cache" (failed to place 1 allocation):
      * Constraint "missing drivers" filtered 6 nodes
    Evaluation "323a522e" waiting for additional capacity to place remainder
dans-mbp:terraform-aws-nomad dan$ 
dans-mbp:terraform-aws-nomad dan$ nomad node-status -address=http://35.176.91.104:4646
ID        DC          Name                 Class   Drain  Eligibility  Status
102d06ca  eu-west-2a  i-0399a0be8ad2fea8f  <none>  false  <none>       ready
7ed6b38e  eu-west-2c  i-09a37ca2e56de4a91  <none>  false  <none>       ready
79c809d2  eu-west-2a  i-045b549c3606367ee  <none>  false  <none>       ready
f2b524d8  eu-west-2c  i-00bb214d9672adfc3  <none>  false  <none>       ready
a1919d6b  eu-west-2b  i-0e1a6cff12d886b09  <none>  false  <none>       ready
e38670c4  eu-west-2b  i-08beb9ce9987a843c  <none>  false  <none>       ready
dans-mbp:terraform-aws-nomad dan$ nomad node-status -address=http://35.176.91.104:4646 102d06ca

error fetching node stats: Unexpected response code: 500 (node is not running a Nomad Client)
ID            = 102d06ca
Name          = i-0399a0be8ad2fea8f
Class         = <none>
DC            = eu-west-2a
Drain         = false
Eligibility   = <none>
Status        = ready
Driver Status = <none>

Node Events
Time  Subsystem  Message

Allocated Resources
CPU         Memory       Disk        IOPS
0/2400 MHz  0 B/985 MiB  0 B/48 GiB  0/0

Allocation Resource Utilization
CPU         Memory
0/2400 MHz  0 B/985 MiB

error fetching node stats: actual resource usage not present

Allocations
No allocations placed

variables.tf

# ---------------------------------------------------------------------------------------------------------------------
# ENVIRONMENT VARIABLES
# Define these secrets as environment variables
# ---------------------------------------------------------------------------------------------------------------------

# AWS_ACCESS_KEY_ID
# AWS_SECRET_ACCESS_KEY
# AWS_DEFAULT_REGION

# ---------------------------------------------------------------------------------------------------------------------
# REQUIRED PARAMETERS
# You must provide a value for each of these parameters.
# ---------------------------------------------------------------------------------------------------------------------

# None

# ---------------------------------------------------------------------------------------------------------------------
# OPTIONAL PARAMETERS
# These parameters have reasonable defaults.
# ---------------------------------------------------------------------------------------------------------------------

variable "ami_id" {
  description = "The ID of the AMI to run in the cluster. This should be an AMI built from the Packer template under examples/nomad-consul-ami/nomad-consul.json. If no AMI is specified, the template will 'just work' by using the example public AMIs. WARNING! Do not use the example AMIs in a production setting!"
  default = "ami-5eeb15b5"
}

variable "cluster_name" {
  description = "What to name the cluster and all of its associated resources"
  default     = "nomad-example"
}

variable "instance_type" {
   description = "What kind of instance type to use for the nomad clients"
   default     = "t2.micro"
}

variable "num_servers" {
  description = "The number of server nodes to deploy. We strongly recommend using 3 or 5."
  default     = 3
}

variable "num_clients" {
  description = "The number of client nodes to deploy. You can deploy as many as you need to run your jobs."
  default     = 6
}

variable "cluster_tag_key" {
  description = "The tag the EC2 Instances will look for to automatically discover each other and form a cluster."
  default     = "nomad-servers"
}

variable "cluster_tag_value" {
  description = "Add a tag with key var.cluster_tag_key and this value to each Instance in the ASG. This can be used to automatically find other Consul nodes and form a cluster."
  default     = "auto-join"
}

variable "ssh_key_name" {
  description = "The name of an EC2 Key Pair that can be used to SSH to the EC2 Instances in this cluster. Set to an empty string to not associate a Key Pair."
  default     = ""
}