Table des matières

Terraform & Proxmox

Le 2023-12-21

Avant-Propos

Terraform est un outil IAC (Infrastructure As Code) développé par Hashicorps.

Il permet grâce à une syntaxe déclarative relativement simple de créer une infrastructure dans le cloud ou en on-premise. Terraform dispose de nombreux fournisseurs (providers) adaptés aux principaux environnements du marché (kubernetes, Azure, AWS, GCP, Openstack, Vsphere, Proxmox, …).

Il est habituellement utilisé pour créer des VM ensuite configurées par des playbooks Ansible

Des changements de licence récents concernant Terraform ont conduit à la création de la fondation Opentofu (https://opentofu.org) visant à créer un outil disposant d'une licence moins restrictive et compatible avec Terraform …

cf le site de Stéphane Robert :

Installation de Terraform

Sur une Debian 12 Bookworm, la dernière version est la 1.6.6 (au 21/12/2023) 

sudo apt install software-properties-common
curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -
sudo apt-add-repository "deb [arch=$(dpkg --print-architecture)] https://apt.releases.hashicorp.com $(lsb_release -cs) main"
sudo apt update
sudo apt install terraform
...
terraform --version
Terraform v1.6.6
on linux_amd64

Mise en oeuvre de Terraform avec le provider BPG/Proxmox

L'objectif est ici d'utiliser Terraform pour déployer automatiquement des VM KVM sur un serveur Proxmox 8.

4 étapes : init, plan, apply, destroy

Les commandes de base Terraform :

1 - init

mkdir infra-prj && cd infra-prj
touch provider.tf main.tf vars.tf

le fichier provider.tf (minimal) - On utilise ici le provider BPG/Proxmox (maintenu depuis la version 0.42.0 et compatible avec Proxmox 8.1)

cf :

et plus particulièrement :

provider.tf
terraform {
  required_providers {
    proxmox = {
      source = "bpg/proxmox"
      version = "0.43"
    }
  }
}
 
provider "proxmox" {
  endpoint  = "https://192.168.1.100:8006/"
  username = "root@pam"
  password = "monmotdepasse"
#  api_token = "terraform@pve!terraform=7625e302-463c-468c-bff5-a06b9763f50e"
  insecure  = true
  ssh {
    agent    = true
    username = "root"
    node {
         name    = "pve"
         address = "192.168.1.100"
    }
  }
}

On initialise le répertoire projet avec terraform init: 

# terraform init

Initializing the backend...

Initializing provider plugins...
- Finding telmate/proxmox versions matching "2.9.11"...
- Installing telmate/proxmox v2.9.11...
- Installed telmate/proxmox v2.9.11 (self-signed, key ID A9EBBE091B35AFCE)

Partner and community providers are signed by their developers.
If you'd like to know more about provider signing, you can read about it here:
https://www.terraform.io/docs/cli/plugins/signing.html

Terraform has created a lock file .terraform.lock.hcl to record the provider
selections it made above. Include this file in your version control repository
so that Terraform can guarantee to make the same selections by default when
you run "terraform init" in the future.

Terraform has been successfully initialized!

You may now begin working with Terraform. Try running "terraform plan" to see
any changes that are required for your infrastructure. All Terraform commands
should now work.

If you ever set or change modules or backend configuration for Terraform,
rerun this command to reinitialize your working directory. If you forget, other
commands will detect it and remind you to do so if necessary.

2 - Validate

le fichier main.tf : il décrit les ressources (VMs, conteneurs, …) à créer :

main.tf
resource "proxmox_virtual_environment_vm" "debian_vm" {
  count = 2
  name      = "test-debian${count.index+1}"
  node_name = "pve"
 
  initialization {
    ip_config {
      ipv4 {
        address = "dhcp"
        # ou encore address = "192.168.1.100/24"
      }
    }
    user_account {
      # do not use this in production, configure your own ssh key instead!
      username = "debian"
      keys  = ["ssh-rsa AAAAB.....UKNwqgOCcE= paul@host"]
      #password = "password"
    }
 
  }
 
  memory {
      dedicated = 1024
  }
 
  network_device {
      bridge = "vmbr0"
      model = "virtio"
  }
 
  lifecycle {
    ignore_changes = [
      network_device, # on conserve l'adresse MAC pour éviter de régénérer la VM 
    ]
  }
 
  operating_system {
    type = "l26"
  }
 
  disk {
    datastore_id = "local-lvm"
    file_id      = proxmox_virtual_environment_file.debian_cloud_image.id
    interface    = "virtio0"
    iothread     = true
    discard      = "on"
    size         = 6
  }
}
 
resource "proxmox_virtual_environment_file" "debian_cloud_image" {
  content_type = "iso"
  datastore_id = "local"
  node_name    = "pve"
 
  source_file {
    # you may download this image locally on your workstation and then use the local path instead of the remote URL
    path      = "https://cloud.debian.org/images/cloud/bookworm/latest/debian-12-genericcloud-amd64.qcow2"
    # path    = "/var/www/html/debian-12-genericcloud-amd64.qcow2"   # chemin local
    file_name = "debian-12-genericcloud-amd64.img"
  }
}
 
resource "random_password" "debian_vm_password" {
  length           = 16
  override_special = "_%@"
  special          = true
}
 
resource "tls_private_key" "debian_vm_key" {
  algorithm = "RSA"
  rsa_bits  = 2048
}
 
output "debian_vm_public_key" {
  value = tls_private_key.debian_vm_key.public_key_openssh
}
}

Pour valider la configuration du fichier: 

  terraform validate

Pour afficher les changements qui seront réalisés : 

  terraform plan

3. Apply

Pour lancer : 

  terraform apply
  ....
  Do you want to perform these actions?
  Terraform will perform the actions described above.
  Only 'yes' will be accepted to approve.
 
  Enter a value: yes
  ...

On peut alors vérifier l'existence des 2 VMs et s'y connecter après avoir récupéré leur adresse IP (connexion console puis ip a)

4. Modification des ressources puis plan

5. On termine par apply

6. Epilogue : on conclut avec un playbook ansible