Files
home-network-k3s/decisions
jakman85andClaude Opus 4.8 c68349f4ab ADR-0015: add non-negotiable egress invariants (default=WAN, scoped kill-switch)
Make the operator's requirement explicit: default (every pod + the nodes) egresses
the local/private WAN, never the VPN; VPN is strictly opt-in via egress-class=vpn;
the kill-switch blackholes ONLY vpn-class. The two classes fail in opposite
directions — internet fails open (WAN), vpn fails closed (blackhole). Added as ADR-0015
Invariants + a default-WAN principle in docs/03, gated by the egress-class/vpn-killswitch
conformance tests.

Co-Authored-By: Claude Opus 4.8 <[email protected]>
2026-08-24 00:52:07 -05:00
..

Architecture Decision Records (ADRs)

ADRs are an append-only ledger of the significant technology and pattern choices for this platform. Each records the context, the decision, the rejected alternatives, and the requirements it serves. Do not edit an accepted decision in place — supersede it with a new ADR.

ADRs are specifications and are immutable to AI agents (R-TEST-06). Agents may draft a proposed ADR and escalate it, but only the human operator/architect approves/accepts or edits ADRs. See ../AGENTS.md §3 and §11.

Process (read before proposing a change)

  1. To change a decision, create a new ADR with the next number and set Status: Proposed, Supersedes: ADR-XXXX. (Agents draft + escalate; the human approves.)
  2. State what new information invalidates the old decision.
  3. On approval, set the new ADR Accepted and the old one Superseded by: ADR-YYYY.
  4. Never silently re-interpret an accepted ADR (see ../AGENTS.md §3).

Template

# ADR-XXXX — <title>
- Status: Proposed | Accepted | Superseded by ADR-YYYY
- Date: <YYYY-MM-DD>
- Serves: <requirement IDs, e.g. R-NET-01, R-NET-06>
- Supersedes: <ADR-ZZZZ or —>

## Context
<forces, constraints, why a decision is needed>

## Decision
<what we chose, stated decisively>

## Alternatives considered
<options and why rejected>

## Consequences
<positive, negative, follow-ups, risks>

Index

ADR Title Status Serves
0001 Kubernetes distribution: k3s Accepted R-PLAT-01
0002 CNI & network policy & ingress: Cilium + Gateway API Accepted R-NET-01..07, R-DNS-01
0003 Distributed storage: Longhorn (+ bulk tier, Velero) Accepted R-STATE-01..04
0004 GitOps engine: Flux CD Accepted R-GITOPS-01..03
0005 VM workloads: KubeVirt + CDI Accepted R-PLAT-03
0006 TLS: cert-manager + Let's Encrypt (DNS-01) Accepted R-TLS-01..03
0007 Secrets: SOPS + age Accepted R-SEC-01
0008 VPN egress model: Gluetun sidecar + Cilium Egress Gateway Superseded by 0012 R-NET-05/06
0009 Automated updates: Flux image automation + Renovate Accepted R-UPD-01..03
0010 Conformance testing: automated, reproducible, behavior-based Accepted R-TEST-01..06
0011 Conformance test tooling: Kyverno + Chainsaw Accepted R-TEST-01..05
0012 VPN egress: single shared in-cluster ExpressVPN gateway Superseded by 0013 R-NET-05/06/07
0013 VPN provider: PIA over OpenVPN-UDP + port forwarding Accepted — provider/protocol only (client+steering superseded by 0015) R-NET-05/06/07
0014 Identity Provider: Keycloak (SSO via OIDC + forward-auth) Accepted R-IDP-01..06
0015 VPN egress steering: node-level tunnel + Cilium Egress Gateway (host kill-switch) Accepted R-NET-05/06/07