The nomad team has been working very hard on making templated deploys easy for this they have released the tech preview of nomad-pack. This talk discusses some of my observations while migrating nomad job files over to nomad-pack

1. 10 things i learned building
Nomad packs
Bram Vogelaar
@attachmentgenie

2. • Used to be a Molecular Biologist
• Then became a Dev, now an Ops
• Currently Cloud Engineer @ The Factory
• Amsterdam HUG organizer
• Almost author => Workload Orchestration Made Easy With Nomad
$ whoami

3. l Open-source tool for dynamic workload scheduling
l Batch, containerized, and non-containerized applications.
l Has native Consul and Vault integrations.
l Has token based access setup.
l Jobs written in (H)ashiCorp (C)onfiguration (L)anguage
https://www.nomadproject.io/
Nomad

4. Nomad Job Structure
job "lorem-ipsum" {
group ”frontend" {
network {
port "http" { to = ”3000” }
}
service {
name = ”lorem"
port. = ”http"
}
task "server" {
driver = "docker"
config {
image = ”cicero/lorem-ipsum:v1.0.0"
ports = ["http"]
}
}
}

5. Surprisingly Dynamic
job "lorem-ipsum" {
group ”frontend" {
network {
port "http" { to = ”3000” }
}
service {
name = ”lorem"
port. = ”http"
}
task "server" {
driver = "docker"
config {
image = ”cicero/lorem-ipsum:v1.0.0"
ports = ["http"]
}
}
}

6. Job configuration includes options for but is not limited to:
• Datacenters
• Region
• Namespace
• Constraints
• Count
• Restart Configuration
• Network
• Volumes
• Service Checks
• Consul Connect
• Resource Limits
• Artifacts
• Templates
• Autoscaler Configuration
Incredibly Dynamic

7. UX Pyramid

8. • Levant
• Templating and packaging tool
• Easily deploy popular applications to Nomad
• Re-use common patterns across internal applications
• Find and share job definitions with the Nomad community
• Jobs written in (H)ashiCorp (C)onfiguration (L)anguage
• Templates are written using Go Template Syntax.
• Nightlies only right now!
Nomad Pack
https://github.com/hashicorp/nomad-pack

9. $ nomad-pack registry list
$ nomad-pack registry add o11y https://github.com/attachmentgenie/nomad-pack-o11y-registry $
$ nomad-pack run grafana --var job_name=dashboard --registry=o11y
$ nomad-pack run packs/grafana -f vars/grafana.hcl –f vars/lab.hcl
Pack Registries
https://github.com/hashicorp/nomad-pack-o11y-registry

10. $ nomad-pack registry list
PACK NAME | REF | METADATA VERSION | REGISTRY | REGISTRY URL
-----------------------------+--------+------------------+-----------------+-----------------------------
alertmanager | latest | 0.0.1 | default | github.com/hashicorp
aws_efs_csi | latest | 0.0.1 | default | github.com/hashicorp
Default registry
mkdir –p $HOME/.nomad/packs/default on offline systems!

11. lorem-ipsum ❯ tree
|-- CHANGELOG.md
|-- README.md
|-- metadata.hcl
|-- outputs.tpl
|-- templates
| |-- _helpers.tpl
| `-- lorem-ipsum.nomad.tpl
`-- variables.hcl
1 directory, 7 files
Pack Structure

12. app {
url = "https://grafana.com/"
author = "Grafana Labs"
}
pack {
name = "grafana"
description = "Grafana is a multi-platform open source analytics and interactive visualization tool."
url = "https://github.com/attachmentgenie/nomad-pack-o11y-registry/grafana"
version = "0.1.0"
}
metadata.hcl

13. variable "datacenters" {
description = "A list of datacenters in the region which are eligible for task placement"
type = list(string)
default = [“dc1”]
}
Variable “resources” {
description = “The resource to assign to the Grafana service task”
type = object({
cpu = number
memory = number
})
default = {
cpu = 200,
memory = 256
}
}
variables.hcl

14. $ cat packs/grafana/templates/grafana.nomad.tpl
….
datacenters = [[ .my.datacenters | toStringList ]]
…
resources {
cpu = [[ .my.grafana_resources.cpu ]]
memory = [[ .my.grafana_resources.memory ]]
}
…
Pack Templates
https://github.com/hashicorp/nomad-pack-community-registry

15. $ nomad-pack plan packs/loki --var version=vX.Y.Z -f vars/loki.hcl
+/- Job: "loki"
+ VaultToken: "s.IJcEJqpsCkGU0mfY3GmnCLSd"
+/- Task Group: "loki" (1 create, 2 in-place update)
+/- Count: "2" => "3" (forces create)
Task: "connect-proxy-loki" Task: "server"
» Scheduler dry-run:
- All tasks successfully allocated.
Plan succeeded
$ nomad-pack nomad-pack run packs/loki --var version=vX.Y.Z -f vars/loki.hcl
CI-CD

16. $ nomad-pack render packs/loki --var version=vX.Y.Z -f vars/loki.hcl -o $WORKSPACE/render
$ nomad run $WORKSPACE/render/loki/loki.nomad
CI-CD Paranoid Version
https://github.com/marketplace/actions/setup-hashicorp-nomad-pack

17. Nomad UI

18. $ cat packs/grafana/templates/grafana.nomad.tpl
job [[ template "job_name" . ]] {
[[ template "region" . ]]
[[ template "namespace" . ]]
….
$ cat packs/grafana/templates/_helpers.tpl
…
[[- define "job_name" -]]
[[- if eq .grafana.job_name "" -]]
[[- .nomad_pack.pack.name | quote -]]
[[- else -]]
[[- .grafana.job_name | quote -]]
[[- end -]]
[[- end -]]
…
Helper template

19. $ cat packs/grafana/templates/_helpers.tpl
…
[[ define "resources" -]]
[[- $resources := . ]]
resources {
cpu = [[ $resources.cpu ]]
memory = [[ $resources.memory ]]
}
[[- end ]]
…
$ cat packs/grafana/templates/grafana.nomad.tpl
…
[[ template " resources " . ]]
…
Abstracting away boring repetitive bits

20. $ cat packs/grafana/templates/_resources.tpl
…
[[ define "resources" -]]
[[- $resources := . ]]
resources {
cpu = [[ $resources.cpu ]]
memory = [[ $resources.memory ]]
}
[[- end ]]
…
$ cat packs/grafana/templates/grafana.nomad.tpl
…
[[ template " resources " . ]]
…
Abstracting away boring repetitive bits

21. Abstracting away boring repetitive bits
$ cat packs/grafana/metadata.hcl
…
dependency ”hashitalks_helpers" {
name = "hashitalks_helpers"
source = "https://github.com/attachmentgenie/hashitalks-registry/helpers"
}
$ cat packs/grafana/templates/grafana.nomad.tpl
…
[[ template "hashitalks_helpers .resources" . ]]
…

22. Currently no clear alternatives/equivalents for:
• Terraform_docs
• Terraform_fmt
• Terraform_tflint
• Terraform_validate
• Terrascan
Wishlist: pre-commit-nomad?

23. $ cat deploy.sh
#!/bin/bash
set -e
nomad-pack run minio -f vars/minio.hcl -f vars/lab.hcl --registry=attachmentgenie
nomad-pack run packs/loki -f vars/loki.hcl -f vars/lab.hcl
nomad-pack run packs/mimir -f vars/mimir.hcl -f vars/lab.hcl
nomad-pack run packs/phlare -f vars/phlare.hcl -f vars/lab.hcl
nomad-pack run packs/tempo -f vars/tempo.hcl -f vars/lab.hcl
nomad-pack run packs/grafana -f vars/grafana.hcl -f vars/lab.hcl
nomad-pack run redis -f vars/redis.hcl -f vars/lab.hcl --registry=attachmentgenie
nomad-pack run packs/grafana_oncall -f vars/grafana_oncall.hcl -f vars/lab.hcl
nomad-pack run packs/prometheus -f vars/prometheus.hcl -f vars/lab.hcl
nomad-pack run packs/promlens -f vars/promlens.hcl -f vars/lab.hcl
Wishlist: Meta package support

24. $ cat deploy.sh
#!/bin/bash
set -e
export NOMAD_ADDR=http://192.168.1.30:4646/ui/jobs
wait-for-url() {
echo "Testing $1"
timeout -s TERM 45 bash -c
'while [[ "$(curl -s -o /dev/null -L -w ''%{http_code}'' ${0})" != "200" ]];
do echo "Waiting for ${0}" && sleep 2;
done' ${1}
echo "OK!"
}
nomad-pack run minio -f vars/minio.hcl -f vars/lab.hcl --registry=attachmentgenie
wait-for-url https://s3.teambla.dev/minio/health/live
nomad-pack run packs/loki -f vars/loki.hcl -f vars/lab.hcl
Wishlist: Dependency health checks

25. Questions ?
The Floor is yours…
bram@attachmentgenie.com
@attachmentgenie
https://www.slideshare.net/attachmentgenie