# Technitium backup on Serenity

Backup Technitium DNS node cloned from the PD pilot for Serenity.

- Repo stack path: `/home/fizzlepoof/repos/truenas-stacks/technitium-serenity`
- Live stack path: `/mnt/user/appdata/technitium-serenity`
- Bind IP: `10.5.30.10`
- DNS ports: `53/tcp`, `53/udp`
- Web console: `http://10.5.30.10/`
- Bootstrap domain if reset from empty config: `technitium-serenity.home.paccoco.com`

This backup node is an active DHCP-advertised backup resolver at `10.5.30.10`. It is kept aligned from PD's live Technitium config and preserves both recursive DNS service and the private `home.paccoco.com` zone when PD is unavailable.

Current mirrored baseline from Pi-hole:
- blocklists:
  - `https://raw.githubusercontent.com/StevenBlack/hosts/master/hosts`
  - `https://big.oisd.nl`
- no custom local DNS entries detected
- no conditional forwarding detected
- no extra dnsmasq fragments detected

Pilot-specific adaptation:
- Production Pi-hole forwards to PD-local Unbound on `127.0.0.1:5335`.
- Because the Technitium pilot uses a dedicated macvlan IP, that loopback-only upstream is not reachable from the pilot without changing production Unbound.
- For pilot safety, Technitium is seeded as a standalone recursive resolver instead of reconfiguring production Unbound.

Notes:
- The stack binds only to `TECHNITIUM_BIND_IP`, so PD must have that secondary address present on `LAN_INTERFACE` before `docker compose up`.
- The helper script adds the pilot IP alias read/write on the live host for the current boot only. That is deliberate for pilot safety.
- Technitium reads the environment initialization only on first boot when `/etc/dns` is empty. If you need to re-seed initial settings, stop the container and clear the config directory first.
- SSO-capable deployments should set the `DNS_SERVER_SSO_*` variables. Keep a known local admin account as rollback because Technitium may only apply initial auth/env seeding cleanly on first boot or with an empty `/etc/dns` config dir.
- For native Authentik OIDC on this pilot, `DNS_SERVER_SSO_ALLOW_SIGNUP` must be `true` at least for the initial SSO user provisioning. Keeping `DNS_SERVER_SSO_ALLOW_SIGNUP_ONLY_FOR_MAPPED_USERS=true` preserves the gate so only users in mapped Authentik groups can auto-provision.
- Authentik native OIDC callback for Technitium is `https://dns.paccoco.com/sso/callback`.
- For Authentik native OIDC, the Technitium OAuth2 provider must have the default OpenID scope mappings attached: `openid`, `email`, and `profile`. Without them, Authentik will mint a token with no OpenID scopes and Technitium fails the `/application/o/userinfo/` call with `Scope mismatch` / `SSO authentication failed`.
- The authoritative zone `home.paccoco.com` is now hosted in Technitium with `dns.home.paccoco.com -> 10.5.30.8`.
- Clients will resolve `dns.home.paccoco.com` only when they query Technitium directly, or after DHCP/cutover points them at Technitium.

- Host interface parent for macvlan: `br0`
- Operational note: this node is refreshed from PD by `/mnt/docker-ssd/docker/compose/technitium-pilot/bin/sync_backup_nodes.sh`, which root cron runs on PD every 15 minutes. Same-host checks from Serenity to `10.5.30.10` are unreliable because of macvlan isolation; verify from another host when testing health.
