Files
home-network-k3s-impl/infra/ansible
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
..

infra/ansible — k3s HA + Cilium bootstrap (Phase 1 T-1.3)

The "Cluster-join" node lifecycle stage (docs/02 stage 3) and the Flux hand-off (T-1.4 call-in). Installs a 3-server HA k3s cluster (embedded etcd), Cilium as the CNI, verifies readiness, then invokes the bootstrap/ entrypoints.

AUTHOR-ONLY — NOTHING HERE HAS BEEN EXECUTED. No ansible-playbook run, no tofu apply, no cluster contacted. The PM static-validates (see below).

Serves R-ENV-01/02, R-PLAT-01, ADR-0001 (k3s), ADR-0002 (Cilium), ADR-0004 (Flux hand-off), ADR-0007 (SOPS).

Prerequisites

  1. tofu apply in ../tofu/ has created the VMs; cloud-init (../cloud-init/) has baselined them (modules, sysctls, Longhorn disk, SSH user).
  2. Inventory reflects the node IPs. inventory/hosts.ini ships aligned with the LOCKED defaults; regenerate from tofu if overridden: cd ../tofu && tofu output -raw ansible_inventory > ../ansible/inventory/hosts.ini
  3. Run from the dev container (has kubectl + helm, used by the Cilium/verify/ Flux plays via delegate_to: localhost).

Run order

cd infra/ansible
ansible-playbook playbooks/site.yml        # everything, in order
# — or step by step —
ansible-playbook playbooks/k3s.yml         # 1. HA k3s (primary --cluster-init, then joins)
ansible-playbook playbooks/cilium.yml      # 2. Cilium CNI (cluster is NotReady until this)
ansible-playbook playbooks/verify.yml      # 3. gate #1: 3 nodes Ready, Hubble up, no kube-proxy
ansible-playbook playbooks/flux-bootstrap.yml   # 4. hand off to bootstrap/ (SOPS then Flux)

What each layer does

Playbook / role Action
k3s.yml / k3s_server k3s server install with --flannel-backend=none --disable-kube-proxy --disable-network-policy --disable=traefik,servicelb; primary --cluster-init, secondaries join via the primary's node-token (fetched, never pre-stored)
cilium.yml / cilium Gateway API CRDs, then Helm cilium with kubeProxyReplacement, k8sServiceHost/Port, gatewayAPI, egressGateway, hubble, l2announcements
verify.yml / cluster_verify waits nodes Ready + Cilium/Hubble rollout; asserts kube-proxy absent
flux-bootstrap.yml / flux_bootstrap calls bootstrap/ (SOPS age key, then flux bootstrap --path=clusters/dev)

Cilium ownership / parity contract (docs/02)

Ansible installs Cilium; the Flux platform/cilium HelmRelease adopts config afterward. The parity-critical values must match between this role's templates/cilium-values.yaml.j2 and that HelmRelease:

  • kubeProxyReplacement: true
  • k8sServiceHost: {{ k3s_api_host }} (= primary node IP, 10.73.0.11 by default)
  • k8sServicePort: 6443

The HelmRelease currently has k8sServiceHost: "REPLACE-ME" — WS-NET must set it to the same value this role uses (surfaced by tofu output primary_node_ip).

Interface assumed of bootstrap/ (authored by other workers, NOT here)

roles/flux_bootstrap invokes two entrypoints via overridable command vars:

  • flux_bootstrap_sops_cmd → bootstrap/sops/install-age-key.sh (Security Engineer, T-1.4): installs the age private key as the sops-age Secret in flux-system. Key never committed (.gitignore guards age.key/*.key).
  • flux_bootstrap_flux_cmd → bootstrap/flux/bootstrap.sh (GitOps Engineer, T-1.4): runs flux bootstrap ... --path=clusters/dev.

These script names/args are assumptions — if the bootstrap deliverables expose different entrypoints, override the two vars in roles/flux_bootstrap/defaults/main.yml; the task graph is unchanged. Flagged for PM reconciliation.

Static validation (PM, in dev container — NOT run here)

yamllint -c ../../ci/yamllint.yaml infra/ansible
ansible-playbook -i inventory/hosts.ini --syntax-check playbooks/site.yml
ansible-lint playbooks/ roles/          # if the profile is enforced for infra/