PowerDNS lua-records (`ifurlup`, `pickclosest`, `ifportup`) cover everything k8gb was doing — geo-aware response selection, health-checked failover, weighted round-robin — at the authoritative DNS layer. Eliminates a separate K8s controller, CRD set, and CoreDNS plugin from every Sovereign. Changes: - platform/k8gb/ deleted (Chart.yaml, values.yaml, blueprint.yaml never authored — only README existed) - products/catalyst/bootstrap/ui/public/component-logos/k8gb.svg deleted - componentGroups.ts: remove k8gb component (PowerDNS already there) - componentLogos.tsx: drop logo_k8gb + k8gb map entry - model.ts DEFAULT_COMPONENT_GROUPS spine: replace k8gb with powerdns - StepInfrastructure.tsx: copy refers to PowerDNS lua-records, not k8gb - provision.html: replace k8gb tile and edges with powerdns - catalog.generated.ts regenerated (now includes bp-powerdns) - docs sweep — every k8gb reference in PLATFORM-TECH-STACK, NAMING- CONVENTION, SOVEREIGN-PROVISIONING, SRE, ARCHITECTURE, GLOSSARY, COMPONENT-LOGOS, IMPLEMENTATION-STATUS, BUSINESS-STRATEGY, TECHNOLOGY-FORECAST, README, infra/hetzner/README, platform READMEs (cilium, external-dns, failover-controller, litmus, flux, opentofu) rewritten to point at PowerDNS lua-records / MULTI-REGION-DNS.md. Historical entries in VALIDATION-LOG.md preserved as audit trail. - New docs/MULTI-REGION-DNS.md — canonical reference for the lua-record patterns (ifurlup all/pickclosest/pickfirst, ifportup, pickwhashed), Application Placement → lua-record selector mapping, when to add a second Sovereign region, operational checks. Closes #171. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
3.7 KiB
ExternalDNS
DNS synchronization (registers/deletes records via the PowerDNS REST API and external cloud DNS APIs where applicable). Per-host-cluster infrastructure (see docs/PLATFORM-TECH-STACK.md §3.1) — runs on every host cluster, primarily on the DMZ block. PowerDNS (see docs/PLATFORM-POWERDNS.md) is the authoritative server for every Sovereign zone; ExternalDNS uses the webhook provider (external-dns-pdns) to write A/AAAA/CNAME records into PowerDNS. Health-checked geo-failover lives in PowerDNS lua-records — see docs/MULTI-REGION-DNS.md.
Status: Accepted | Updated: 2026-04-27
Overview
ExternalDNS synchronizes Kubernetes resources (Gateway, Service, Ingress) with external DNS providers, enabling automatic DNS record management.
Architecture
flowchart TB
subgraph K8s["Kubernetes"]
GW[Gateway API]
Svc[Services]
ExtDNS[ExternalDNS]
end
subgraph DNS["DNS Providers"]
PDNS[PowerDNS<br>(authoritative — every Sovereign zone)]
CF[Cloudflare]
R53[Route53]
HDNS[Hetzner DNS]
end
GW --> ExtDNS
Svc --> ExtDNS
ExtDNS --> PDNS
ExtDNS --> CF
ExtDNS --> R53
ExtDNS --> HDNS
Supported DNS Providers
| Provider | Availability |
|---|---|
| Cloudflare | Always |
| Hetzner DNS | If Hetzner chosen |
| AWS Route53 | If AWS chosen |
| GCP Cloud DNS | If GCP chosen |
| Azure DNS | If Azure chosen |
Configuration
ExternalDNS Deployment
apiVersion: apps/v1
kind: Deployment
metadata:
name: external-dns
namespace: external-dns
spec:
template:
spec:
containers:
- name: external-dns
image: registry.k8s.io/external-dns/external-dns:v0.14.0
args:
- --source=gateway-httproute
- --source=gateway-grpcroute
- --source=service
- --provider=cloudflare
- --cloudflare-proxied
- --txt-owner-id=openova
- --txt-prefix=_externaldns.
env:
- name: CF_API_TOKEN
valueFrom:
secretKeyRef:
name: cloudflare-credentials
key: api-token
PowerDNS Integration (geo + health-checked failover)
ExternalDNS writes plain A/AAAA/CNAME records into PowerDNS via the REST API. Geo-aware and health-checked failover responses are owned by PowerDNS lua-records, written by the catalyst-dns controller — ExternalDNS does NOT manage lua-record content.
flowchart LR
subgraph Region1["Region 1"]
App1[Application]
ExtDNS1[ExternalDNS]
end
subgraph Region2["Region 2"]
App2[Application]
ExtDNS2[ExternalDNS]
end
subgraph PDNS["PowerDNS Authoritative"]
ZoneAPI[REST API]
Lua[lua-records (ifurlup, pickclosest)]
end
ExtDNS1 -->|"plain A/AAAA"| ZoneAPI
ExtDNS2 -->|"plain A/AAAA"| ZoneAPI
ZoneAPI --- Lua
See docs/MULTI-REGION-DNS.md for the lua-record patterns.
Record Types
| Source | Record Type | Example |
|---|---|---|
| Gateway | A/CNAME | api.<domain> |
| Service (LoadBalancer) | A | svc.<domain> |
| catalyst-dns (lua-record author) | LUA A | app.<domain> (geo + health-checked) |
TXT Registry
ExternalDNS uses TXT records to track ownership:
_externaldns.api.<domain> TXT "heritage=external-dns,external-dns/owner=openova"
This prevents ExternalDNS from modifying records it doesn't own.
Part of OpenOva