Inventory Reference

The Ansible inventory file hosts.yml defines all hosts and their groupings.

Host groups

Group	Purpose	Used by
controller	The devcontainer (localhost)	tools, cluster roles
turing_pis	Turing Pi BMC hosts	flash, known_hosts roles
<bmc>_nodes	Nodes on a specific Turing Pi	flash, all node roles
extra_nodes	Non-Turing Pi servers	All node roles
all_nodes	Union of all node groups	known_hosts, move_fs, update_packages, k3s

Naming conventions

Turing Pi node groups

Node groups for Turing Pi boards must be named <bmc_hostname>_nodes. The flash role uses this convention to discover which nodes belong to each BMC.

Examples:

• BMC hostname turingpi → node group turingpi_nodes

• BMC hostname turingpi-2 → node group turingpi-2_nodes

The all_nodes group

The all_nodes group is a union of all node groups. Define it using children:

all_nodes:
  children:
    turingpi_nodes:
    extra_nodes:

Per-node variables

Variable	Required	Values	Description
slot_num	For Turing Pi nodes	1–4	Physical slot on the board (slot 1 nearest coin battery)
type	For Turing Pi nodes	rk1, pi4	Compute module type (determines OS image)
root_dev	Optional	Device path	Target block device for OS migration (e.g. /dev/nvme0n1)
nvidia_gpu_node	Optional	true/false	Set true for nodes with an NVIDIA GPU. Installs the NVIDIA driver and container toolkit, configures k3s containerd with the NVIDIA runtime, and labels the node nvidia.com/gpu.present=true. Required for the llama.cpp CUDA service.
workstation	Optional	true/false	Applies workstation=true:NoSchedule taint and node-role=workstation label. Only tolerating workloads (GPU, monitoring) schedule here.
node_ip	Optional	IP address	Forces K3s to use this IP (passed as --node-ip). Required for multi-homed nodes where the default route interface is on the wrong subnet.
flannel_iface	Optional	Interface name	Forces flannel’s VXLAN tunnel to use this interface (passed as --flannel-iface). Must match the interface carrying node_ip. Required alongside node_ip on multi-homed nodes.

Example: Turing Pi only

controller:
  hosts:
    localhost:
      ansible_connection: local

turing_pis:
  hosts:
    turingpi:
  vars:
    ansible_user: "{{ tpi_user }}"

turingpi_nodes:
  hosts:
    node01:
      slot_num: 1
      type: pi4
    node02:
      slot_num: 2
      type: rk1
      root_dev: /dev/nvme0n1
    node03:
      slot_num: 3
      type: rk1
      root_dev: /dev/nvme0n1
    node04:
      slot_num: 4
      type: rk1
      root_dev: /dev/nvme0n1
  vars:
    ansible_user: "{{ ansible_account }}"

all_nodes:
  children:
    turingpi_nodes:

Example: Standalone servers only

controller:
  hosts:
    localhost:
      ansible_connection: local

extra_nodes:
  hosts:
    server1:
    server2:
    server3:
  vars:
    ansible_user: "{{ ansible_account }}"

all_nodes:
  children:
    extra_nodes:

Example: Mixed (Turing Pi + extra nodes)

controller:
  hosts:
    localhost:
      ansible_connection: local

turing_pis:
  hosts:
    turingpi:
  vars:
    ansible_user: "{{ tpi_user }}"

turingpi_nodes:
  hosts:
    node01:
      slot_num: 1
      type: pi4
    node02:
      slot_num: 2
      type: rk1
      root_dev: /dev/nvme0n1
  vars:
    ansible_user: "{{ ansible_account }}"

extra_nodes:
  hosts:
    nuc1:
    nuc2:
  vars:
    ansible_user: "{{ ansible_account }}"

all_nodes:
  children:
    turingpi_nodes:
    extra_nodes: