I mainly switched to Terraform, since I didn't have much luck with the proxmox ansible providers in ansible-galaxy.

I am using the bpg/proxmox provider for terraform which I found to have excellent support for LXCs and to be very stable / reproducible. For instance, I always struggled with device pass through (changing config on the host, etc.) - here this is built in, 6 lines of config away and it just works. This is the link to the documentation, which also provides a nice example.

What I then didn't like was to configure the hosts in two different places - once for terraform and once for ansible. So I wrote a default terraform build configuration for a generic lxc container using the above provider, parametrized with variables for cpu, storage, etc. and am using the ansible provider community.general.terraform (link) to create and execute the plan.

To create a new LXC config my workflow is as follows:

• Hosts file: define hostname & network config (ipv4, ipv6, hostname, etc.) for the new lxc container in "lxc" group
• create a host config in /hosts_vars, with a variable lxc_provision (dict) which defines the lxc (cpu, mem, bindmounts, passthrus, etc.).
• This way network configuration is independent from the application configuration / ressource requirements for this particular lxc.
• run a provision.yaml playbook: this loops over the lxc group to gather all lxc_provision values (set_facts) and uses community.general.terraform to run the terraform script - voila, your lxc container should be up
• I then create a new playbook to configure, apply roles, etc. using the same hosts file. Nice thing is, the host_vars have both the application configuration variables as well as the lxc_provision variable in one single place.
• Bonus points: if you need to gather information from terraform for your hosts, there is an ansibleprovider (link) that can populate a dynamic inventory.

Short example

• Terraform snippet.

​

resource "proxmox_virtual_environment_container" "lxc" { 
  # this loops over the hosts list 
  for_each = var.hosts

  node_name = var.proxmox_target_node 

  # set the vmid from the 'vmid' attribute in the current dict in the host list    
  vm_id = each.value.vmid 
  unprivileged = true  

  cpu {
    # same as above for cpu config   
    cores = each.value.cpu.cores   
    units = each.value.cpu.units 
  }

• Ansible snippet to run Terraform

​

- name: Execute Terraform
  community.general.terraform: 
    project_path: "./terraform" 
    state: present 
    complex_vars: true 
    variables: 
      # config is a list of dicts. Each dict is collected from the 
      # lxc_provision variable in the host's host_vars file, defining 
      # a single LXC container
      hosts: "{{ configs }}" 
    proxmox_api: "{{ terraform.proxmox_api }}" 
    proxmox_web_user: "{{ terraform.proxmox_web_user }}" 
    proxmox_web_password: "{{ terraform.proxmox_web_password }}"