The DNS reference generator transfers each zone from the nameservers
public NS discovery returns. The home IPv6 reverse zone
(0.d.4.0.0.c.7.9.e.0.a.2.ip6.arpa) is delegated only to Hurricane
Electric, which refuses AXFR, so generation aborted before committing
any zone. Our own authoritative servers (ns1/ns2.h.nul.ie) serve that
zone and permit transfers but aren't in its public delegation, as their
addresses are dynamic.
When a zone's delegated servers all refuse, retry against the union of
nameservers discovered for every other zone. That pool includes
ns1/ns2.h.nul.ie via the h.nul.ie NS records, resolved to their current
addresses at query time, so the reverse zone transfers from the same
reachable servers h.nul.ie already uses. Zones whose own servers work
are unaffected; the fallback only runs after their transfers fail.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Generate forward and reverse record tables from authoritative AXFRs
while preserving handwritten Markdown outside per-zone markers. Run the
generator in CI and link the reference from the relevant docs.
jackos1998