Authoritative cluster
Four authoritative groups (ns1–ns4) on four mutually independent network providers: three anycast groups plus a Singapore load-balanced group (fixed elastic-IP entry, 1×N backends added, removed or swapped at will) — 15 enabled POPs in total. If any one provider fails entirely, the other three keep answering.
Data sync
The primary lives in Singapore, hidden behind the protection layer, never answering the public internet; every edge node long-polls for changes — a record edit reaches all nodes within seconds. Edges hold only encrypted replicas and no plaintext ever lands on their disks; each node answers from a resident in-memory snapshot, and data swaps never interrupt service.
Authoritative engine: dnsd
In-house authoritative engine: every zone lives in a resident in-memory snapshot, the query hot path is lock-free, and data swaps never pause answering. Rough pool capacity ≈ 525,000 QPS (15 POPs × a 35,000 per-node measured floor); network-wide load today is under 10 QPS (as of 2026-08).
Front-line defense: dnsway
An in-house defense layer in front of every node's authoritative responder: reputation-tiered rate limiting, UDP amplification mitigation (response-size clamping for unverified sources plus TC challenges forcing genuine-source TCP), and automatic banning of anomalous query patterns. It exists to stop people using free DNS as an attack reflector — normal queries never notice it.
Split-horizon
Answers vary by the querying client's location (GeoIP, EDNS Client Subnet supported): 18 preset routes (Mainland China / HK-MO-TW / US-JP-KR-SG + CN Telecom / Unicom / Mobile / CERNET + six continents), plus user-defined IP-range routes. Routes are purely an answer-steering dimension — they classify where the query comes from, not where data lives: all authoritative data is stored in Singapore only.
Dogfooding
anyns.io and n.ht themselves resolve on this cluster — one dig verifies it. The cluster served its builders for a long time before opening to anyone else.