# 107 — `dns`

Homelab DNS server (Technitium). Replaces the dnsmasq that lived on [124 — authentik](124-authentik.md); single-purpose, one job.

## At a glance
- **Hostname:** `dns`
- **IP:** `192.168.8.2` (static — stable, decoupled from any app)
- **Privilege:** privileged (Docker-in-LXC, `features: nesting=1`)
- **Resources:** 1 core / 1 GiB / 8 GiB rootfs
- **Created:** 2026-06-01, Debian 13. Its own resolver is `1.1.1.1` (no circular dependency on the DNS it serves).

## Role
Authoritative split-horizon DNS for `hubris.network` on the LAN/mesh, plus recursive forwarding (`1.1.1.1`, `8.8.8.8`) for everything else. Technitium runs in Docker (`technitium/dns-server:latest`, `network_mode: host`), web console on `:5380`.

## The `hubris.network` zone
- Specific A overrides: app names → `192.168.8.175` (Caddy), `nfs-export → 192.168.8.200`, `auth/sso/...` as needed.
- `auth.hubris.network → 82.165.190.79` (VPS Authentik), `sso.hubris.network → 192.168.8.175` (LAN forward-auth outpost).
- **Wildcard** `*.hubris.network → 82.165.190.79` — mirrors the public IONOS wildcard so undefined names (e.g. `netbird`) resolve to the VPS, matching public behaviour.
- **MX / SPF-TXT / CAA replicated from public** so an authoritative zone doesn't shadow `hubris.network` email/cert records.

## Config / access
- `/opt/technitium/docker-compose.yml`; admin password in `/opt/technitium/admin_password.txt` (mode 600 — sops-encrypt in Phase 5).
- Console: `http://192.168.8.2:5380` (user `admin`).
- API: `http://192.168.8.2:5380/api/...` (token via `/api/user/login`). Zone was built via the API.

## Who points here
- **NetBird mesh peers:** nameserver group `home-lab-dns` (`hubris.network` → this server). *Note: the [NetBird managed DNS zone](124-authentik.md) still answers most app names directly, bypassing this — see the single-source-of-truth decision.*
- **Homelab DHCP clients:** Technitium's own DHCP scope hands out `192.168.8.2` as the DNS server for `192.168.8.x` leases (see DHCP section below).
- **Plain LAN clients (`192.168.178.x`):** Fritz!Box DHCP still hands out Fritz!Box itself (`192.168.178.1`) as DNS — no split-horizon for non-mesh clients. Changing this requires a secondary DNS fallback, which Fritz!OS 8.x doesn't expose in a single DHCP field.
- **Secondary:** Mac Mini (planned, Phase 3) via AXFR zone transfer.

## DHCP

Technitium also runs a DHCP server for the homelab subnet (enabled 2026-06-02):
- **Scope:** `homelab` — `192.168.8.100 – 192.168.8.240`
- **Gateway:** `192.168.8.1` (Proxmox `vmbr0` alias)
- **DNS:** `192.168.8.2` (self)
- **Lease time:** 24 h

Replaces the DHCP that was previously served by the Slate AX router. Static-IP LXCs (below `.100`) are unaffected.

## Related
- [124 — authentik](124-authentik.md) — retired host of the old dnsmasq
- [DNS split-horizon](../infrastructure/dns.md)
- [Mesh](../infrastructure/mesh.md)

## Changelog

### 2026-06-02 — DHCP server enabled; replaces Slate AX DHCP
Enabled Technitium's built-in DHCP server for `192.168.8.0/24` (scope `homelab`, range `.100–.240`, gateway `192.168.8.1`, DNS self). Previously the Slate AX sub-router served DHCP for the homelab subnet. With the Slate AX retired and Proxmox now the subnet router, Technitium takes over DHCP. Configured via the Technitium API (`/api/dhcp/scopes/set`). DHCP LXCs kept their Slate AX leases until expiry, then renewed from Technitium.

### 2026-06-01 — created; replaced dnsmasq on 124
Stood up Technitium at `192.168.8.2`, imported the split-horizon zone (specific A + wildcard + MX/SPF/CAA), made it the primary nameserver in the NetBird `home-lab-dns` group. Verified all names resolve with dnsmasq/124 stopped; [LXC 124 retired](124-authentik.md).