Files
home-network-k3s-impl/infra/cloud-init/README.md
T
jakman85andClaude Opus 4.8 f2a7e42068 Phase 1 (author-only): node provisioning IaC — tofu + cloud-init + Ansible (T-1.1/1.2/1.3)
OpenTofu libvirt module (k3s-dev NAT 10.73.0.0/24, 3x 6GiB/4vCPU VMs, 20G OS +
40G thin data, host-passthrough), cloud-init baseline (k3s/Cilium/Longhorn
prereqs, static net), Ansible k3s-HA + Cilium (kube-proxy replacement, Gateway
API, Hubble; flannel/kube-proxy/Traefik disabled). PM fix: escape ${...} in a
cloud-init template comment (tofu templatefile parse). tofu fmt/init/validate =
Success; ansible --syntax-check + yamllint pass. NOTHING executed (no apply).

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>
2026-08-16 01:21:00 -05:00

2.3 KiB

infra/cloud-init — first-boot baseline templates

Phase 1 T-1.2. The "Baseline" node lifecycle stage (docs/02 stage 2). These templates are consumed by the OpenTofu libvirt_cloudinit_disk in ../tofu/ (via templatefile()), one seed per node. Authoring only — never applied.

Serves R-ENV-01 (nodes are "created, baselined, cluster-joined, managed as code") and lays the kernel/OS floor ADR-0001 (k3s) + ADR-0002 (Cilium) + ADR-0003 (Longhorn) + ADR-0005 (KubeVirt) require.

Files

  • user-data.yaml.tftpl — #cloud-config: login user + injected SSH public key, hostname, package baseline, kernel modules, sysctls, Longhorn data-disk mount, swap-off.
  • meta-data.yaml.tftpl — NoCloud instance-id / local-hostname.
  • network-config.yaml.tftpl — netplan v2 static IP (DHCP is off on the NAT).

${...} tokens are OpenTofu template vars filled by ../tofu/main.tf (hostname, fqdn, username, ssh_authorized_key, ip, prefix, gateway) — they are not cloud-init/Jinja.

Baseline (cloud-init's job) vs. Ansible's job

cloud-init does (here) Ansible does (T-1.3)
user + SSH public key, hostname install k3s (HA, embedded etcd)
static networking join nodes, disable flannel/kube-proxy/traefik/servicelb
overlay, br_netfilter, iscsi_tcp, dm_crypt, nfs modules install Cilium (kube-proxy replacement, Gateway API, Hubble)
bridge-nf + ip_forward sysctls, inotify limits verify readiness
open-iscsi + nfs-common (Longhorn client prereqs) Flux + SOPS bootstrap handoff
mount /dev/vdb at /var/lib/longhorn —
swapoff + strip swap from fstab —

Why these specifics

  • overlay / br_netfilter + bridge-nf-call sysctls — pod networking / iptables bridging Cilium and kube-networking need.
  • ip_forward / forwarding — routing between pods, nodes, and egress.
  • iscsi_tcp + open-iscsi (iscsid) and nfs / nfs-common — Longhorn attaches volumes over iSCSI and uses the NFS client for backup/RWX (ADR-0003).
  • dm_crypt — headroom for Longhorn volume encryption.
  • swap off — kubelet/k3s expectation.
  • qemu-guest-agent — lets libvirt/tofu read guest state.

Nested-virt for KubeVirt (Phase 5) comes from the tofu host-passthrough CPU mode, not from here.