Add the at-home peer (10.90.0.3) and list ${WG_CLIENT_CIDR} in the PiHole
DNS frontends' loadBalancerSourceRanges. wg0 is a Cilium device, so tunnel
clients reach the source-range check untranslated; a LAN-only list is
predicted to drop their DNS. Adds an L0 guard that both ranges are present
and every range is RFC1918, and corrects the README's SNAT and IPv6 claims.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
platform/coredns/coredns-custom.yaml has always said its split-horizon is for
PODS and deferred LAN clients to "PiHole split-horizon". PiHole served no DNS:
its Service was ClusterIP with ports 80 and 4180 only. The LAN half of R-DNS-03
that docs/09 and the README's Phase 2 row both claim did not exist, so LAN
clients ran on hand-maintained per-client dnsmasq files - one went stale after
the dev decommission and cost the operator sonarr.home.keithjackson.dev. The
SOHO router that owns 192.168.2.0/24 cannot cover for it either: it strips
RFC1918 answers for public domains as rebind protection and returns NOERROR
with no answer.
EXPOSURE (apps/wave-0/pihole-dns.yaml, hand-written, placed into wave 0 by
render.py's EXTRA_UNITS - the schema has no field for a LoadBalancer Service, a
pinned lbipam VIP, a sharing key, source ranges or UDP, the same reason
apps/vms/unifi and platform/crafty hand-write theirs):
- two Services, udp/53 and tcp/53, sharing one pinned VIP
${PIHOLE_DNS_VIP} = 192.168.2.23 on prod, the next free address in the
.20-.30 pool (pool status IPsUsed 3 of 11; .20 Gateway, .21 unifi, .22
crafty; arping from a LAN host got no reply).
- no external-dns hostname annotation: nothing public is created, and
platform/externaldns/ is untouched.
ANSWERS (catalog/pihole.yaml env - declarative, no reconciler): PiHole v6 takes
every FTL setting as an FTLCONF_ environment variable and treats it as
env-forced, applied ahead of pihole.toml on every cold start and read-only in
the UI. That is a real declarative entry point, which the Keycloak and CNPG
CronJob reconcilers exist precisely because their state lacks, so a reconciler
here would be ceremony. misc.dnsmasq_lines carries a wildcard
address=/<zone>/<GATEWAY_VIP> plus one longer-domain override per L4 service
(unifi, crafty-mc, pihole-dns); dnsmasq resolves overlaps by longest matching
domain, so precedence is structural and a newly onboarded Gateway-fronted
service needs no DNS change. dns.upstreams is declared too - the live pod
carried hand-set upstreams that no manifest knew about and that every restart
discarded.
externalTrafficPolicy Cluster, NOT Local, and loadBalancerSourceRanges for the
LAN restriction. Measured on prod, Cilium 1.20.1: the L2 announcer does not
filter lease candidates by which nodes hold a backend - the two Services landed
on k3s-prod-3 and k3s-prod-2 while the pod ran on k3s-prod-1 - and it keeps
renewing after the pod moves away, so with Local a reschedule leaves LAN DNS
dead indefinitely. Cluster serves the VIP from any node; the LAN restriction
moves to loadBalancerSourceRanges, which Cilium enforces in eBPF on the VIP
before load-balancing (verified by narrowing the range to exclude the test
client and back). The cost is SNAT: forwarded queries reach PiHole from the
ingress node, so PiHole's per-client rate limit is disabled in the catalog or
the whole LAN would count as one client against its 1000-per-60s default.
Proven from a LAN host (192.168.2.132) against 192.168.2.23 with the pod and
both leases on three DIFFERENT nodes: sonarr/grafana/nextcloud/keycloak/apex
-> 192.168.2.20, unifi -> .21, crafty-mc -> .22, pihole-dns -> .23, recursion
(cloudflare.com, github.com, debian.org) intact over both udp and tcp, AAAA
NODATA, NXDOMAIN outside the zone, and still answering after a forced
prod-1 -> prod-2 reschedule.
Co-Authored-By: Claude Opus 5 <[email protected]>
jakman85andClaude Opus 5.5