Self-Hosted SSO for 25 Services: Authelia OIDC on Kubernetes

Originally published at woitzik.dev Disclosure: This post contains Amazon affiliate links (marked with *). If you buy through them, I earn a small commission at no extra cost to you. I only link gear I actually own and use daily. Every internal service in my homelab goes through the same authentication gate: Authelia. Proxmox, PBS, Grafana, ArgoCD, Headscale, ArgoCD, Uptime Kuma, Paperless, Nextcloud — 25+ web services, one login, one session, one set of access rules. The OIDC provider, the Postgres backend, the session store, and the secrets are all running inside k3s, backed by CNPG, Redis, and Vault. This article is the full implementation: how the pieces fit together, why certain design decisions were made, and the specific bugs that bit me along the way. View the complete homelab infrastructure source on GitHub 🐙 The Architecture Authelia runs as a Kubernetes Deployment in the apps namespace, protected by the same default-deny NetworkPolicy that applies to everything else. It has three dependencies: PostgreSQL — CNPG-managed postgres-authelia cluster in the database namespace Redis — session store, ephemeral (no persistence needed) Vault — hmac_secret, OIDC private keys, JWT secrets, session secrets The Traefik ForwardAuth middleware sits in front of every service. When a request hits Traefik, the middleware sends a verification request to Authelia's /api/verify endpoint. Authelia checks the session cookie, validates the OIDC token if applicable, and returns a 200 (allowed) or 401 (redirect to login). # kubernetes/apps/authelia/middleware.yml apiVersion : traefik.io/v1alpha1 kind : Middleware metadata : name : authelia namespace : apps spec : forwardAuth : address : " http://authelia.apps.svc.cluster.local:9999/api/verify" trustForwardHeader : true authResponseHeaders : - Remote-User - Remote-Groups - Remote-Email Every IngressRoute that needs protection adds middlewares: [{name: authelia}] . Services that need API-level protection (not browser-based) use OIDC