Files
home-network-k3s-impl/infra/tofu
jakman85andClaude Opus 4.8 7a34590b19 fix(dns): add resilient fallback resolver to k3s nodes (PiHole primary + pfSense fallback)
Root cause: the k3s nodes shipped with a SINGLE upstream resolver, PiHole
(192.168.1.18), set by cloud-init/netplan. PiHole answers the local jackson.lan
zone instantly but its external/recursive resolution flaps — verified 0/25 for
public names (registry-1.docker.io, api.cloudflare.com, quay.io, ghcr.io,
google.com) while gitea.jackson.lan resolved 5/5. A single upstream is a hard
SPOF: both containerd image pulls ("lookup registry-1.docker.io: Try again")
and CoreDNS ("forward . /etc/resolv.conf" -> pods' external DNS, e.g.
external-dns -> Cloudflare) fail whenever PiHole recursion is down. CoreDNS
logs were flooded with "read udp ...->192.168.1.18:53: i/o timeout".

Fix (additive, no policy bypass): keep PiHole PRIMARY (preserves jackson.lan +
network ad-blocking) and ADD the pfSense gateway (192.168.1.1) as a FALLBACK,
which resolves the public zones reliably (verified). The resolver fails over to
the fallback when PiHole times out.

- node_baseline: netplan drop-in (99-k3s-dns.yaml) with both nameservers +
  "Apply netplan" handler; new node_baseline_dns_* defaults; tagged `dns`.
  Applied to all 3 nodes via playbooks/node-baseline.yml --tags dns.
- tofu: initialization.dns.servers now lists [dns_server, network_gateway] so a
  fresh cloud-init/netplan build stays in parity with the drop-in.

Verified: all external names resolve cluster-wide (10/10, zero timeouts) from
multiple pods after a CoreDNS restart; CoreDNS i/o-timeout floods stopped;
split-horizon (keycloak.home.keithjackson.dev -> Gateway VIP) intact.

NOTE: a SEPARATE, pre-existing WAN-egress outage (ICMP + TCP 443 to the internet
time out from every node while the LAN/pfSense resolver work) still blocks image
pulls, external-dns->Cloudflare, and Flux remote bases. That is a pfSense
NAT/firewall/WAN problem outside this repo, flagged for PM follow-up.

Co-Authored-By: Claude Opus 4.8 <[email protected]>
2026-08-28 23:30:59 -05:00
..
2026-08-27 19:53:46 -05:00

infra/tofu — dev/test cluster nodes (OpenTofu + Proxmox VE)

Provisions the "Create" lifecycle stage (docs/02): 3 cloud-init'd VMs on the Proxmox VE box, each with an imported OS disk and a blank Longhorn data disk. (Migrated from the old memory-constrained libvirt host; provider is now bpg/proxmox.)

APPLIED AND LIVE. These three VMs are the running dev cluster — k3s-dev-1/2/3, k3s v1.31.5, carrying the whole platform. Treat any tofu apply/destroy here as an operation on production-for-dev, and note the state file caveat below.

Serves R-ENV-01/02, R-PLAT-01, ADR-0001 (k3s substrate).

What it builds (defaults = the LIVE cluster, verified 2026-08-26)

Resource Value
Proxmox node proxmox
Disk datastore Storage (ZFS, 4.3TB)
Image/snippet datastore local (dir; content = iso + snippets)
Bridge vmbr0 (no VLAN)
Nodes k3s-dev-1/2/3 at 192.168.1.50/.51/.52, gw 192.168.1.1, DNS 192.168.1.18
Per node 6 vCPU, 16 GiB RAM, cpu type host (nested virt for KubeVirt — real KVM confirmed in-guest)
OS disk 64 GiB, virtio0 (/dev/vda, boot), imported from the Debian 12 cloud image
Data disk 128 GiB, virtio1 (/dev/vdb) → /var/lib/longhorn (mounted by cloud-init; Longhorn reports ~125 GiB usable per node)
Cloud-init native initialization (static IP + DNS) + user-data snippet for the baseline
Reserved 192.168.1.53–.60 for Cilium L2 ingress VIPs (surfaced in outputs). In use: .53 shared Gateway, .54 UniFi

⚠️ State file

terraform.tfstate is gitignored and lives only on the workstation that ran the apply. On a fresh workstation it is absent — and a tofu apply with empty state will try to create three VMs that already exist. Recover the state file (or tofu import the existing VMs) before running anything that plans changes. tofu plan against empty state is itself harmless, but read the plan: "3 to add" means you are missing state, not that the cluster is gone.

All sizing/IPs/counts/placement are variables — see variables.tf.

Files

  • versions.tf — OpenTofu 1.9.0 pin + bpg/proxmox ~> 0.66; provider block with endpoint scheme-normalization (see below).
  • variables.tf — every knob (Proxmox placement, counts, sizing, IPs, image, SSH key).
  • main.tf — cloud image download, per-node user-data snippet, and the 3 VMs.
  • outputs.tf — node IPs/names, primary_node_ip, k3s_api_endpoint, rendered ansible_inventory.
  • terraform.tfvars.example — copy to terraform.tfvars; only ssh_authorized_key required.

Operator prerequisites (before tofu apply)

  1. Enable snippets content on the local datastore. The rich first-boot baseline (users, packages, kernel modules, Longhorn mount, swap-off) is shipped as a cloud-init user-data snippet. In the Proxmox UI: Datacenter → Storage → local → Edit → Content → add Snippets. Without this the proxmox_virtual_environment_file (user-data) resource fails. (Alternatively point image_datastore at any datastore that has snippets enabled.)
  2. Endpoint scheme. If the operator env file exports PROXMOX_VE_ENDPOINT without https://, the provider talks HTTP and eats a 301. Either fix the env file to include the scheme, or export TF_VAR_proxmox_endpoint="$PROXMOX_VE_ENDPOINT" so tofu normalizes it (prepends https://).
  3. pfSense NAT — DONE, live. The workstation reaches the nodes and the kube-API across it: SSH 192.168.2.102:2250/2251/2252 → 192.168.1.50/.51/.52:22, and kube-API 192.168.2.50:6443 → kube-vip VIP 192.168.1.49:6443. infra/ansible/inventory/hosts.ini is hand-maintained for this mapping — do not regenerate it from tofu output -raw ansible_inventory, which knows nothing about the NAT and would overwrite it.

Auth (env only — never in tofu vars/state)

The provider reads these from the environment; the API token is never a tofu variable, so it never enters state, vars, or plan output. You do NOT export these by hand — they live encrypted in secrets.sops.env and the tf.sh wrapper decrypts + exports them (and sets TF_VAR_proxmox_endpoint for scheme normalization) at runtime:

PROXMOX_VE_ENDPOINT=https://192.168.2.102:8006/
PROXMOX_VE_API_TOKEN=user@realm!tokenid=SECRET
PROXMOX_VE_INSECURE=true

See REMOTE-STATE.md for the encrypted-secrets + wrapper flow.

Usage (operator — NOT run here)

All secrets come from the encrypted secrets.sops.env via the tf.sh wrapper, run inside the dev container (which has sops + the age key):

cp infra/tofu/terraform.tfvars.example infra/tofu/terraform.tfvars   # set ssh_authorized_key
./infra/devcontainer/dev.sh run ./infra/tofu/tf.sh init
./infra/devcontainer/dev.sh run ./infra/tofu/tf.sh plan
./infra/devcontainer/dev.sh run ./infra/tofu/tf.sh apply
# hand the node IPs to Ansible:
./infra/devcontainer/dev.sh run ./infra/tofu/tf.sh output -raw ansible_inventory > infra/ansible/inventory/hosts.ini

Hand-off contract

  • primary_node_ip / k3s_api_endpoint (192.168.1.50:6443) is the value the Ansible Cilium bootstrap and the Flux platform/cilium HelmRelease must BOTH use for k8sServiceHost / k8sServicePort (docs/02 parity contract).
  • Destroy/rebuild proof: name-keyed for_each means tofu destroy -target='proxmox_virtual_environment_vm.node["k3s-dev-2"]' then tofu apply re-creates just that node (stop_on_destroy allows the clean stop); Ansible re-joins it; Longhorn replicas reconverge (nodes are cattle).

Static validation (PM, offline)

tofu fmt -check -recursive
tofu init            # fetches the bpg provider (network, read-only)
tofu validate