ns.avonet.cz publishes IPv6 but doesn't answer on it.

Has both IPv4 (A) and IPv6 (AAAA) addresses.

This is a saved measurement from 2026-11-15 17:54 UTC. Check ns.avonet.cz live now

F
IPv6 readiness
Publishes IPv6 but doesn't answer on it — worse than having none.
Website over IPv6
ns.avonet.cz has an AAAA record, but nothing answered on ports 443 or 80. IPv6 visitors wait for a timeout before falling back to IPv4.
✗ 2a00:6500:0:11::a no answer
broken
Mail servers (MX) have IPv6
At least one mail server has no AAAA record (1 of 3 checked do).
ms.avonet.cz ✓mx1.avonet.cz ✗spool.avonet.cz ✗
partly
Nameservers have IPv6
3 of 3 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.
ns.avonet.cz ✓sns.avonet.cz ✓tns.avonet.cz ✓
yes

What's keeping ns.avonet.cz from an A

  1. Fix or remove the AAAA record for ns.avonet.cz
    Something published an IPv6 address but nothing answers on it, so IPv6 visitors wait for a timeout first. Either make the server listen on IPv6 (and allow ports 443/80 through its firewall), or delete the AAAA record until it does.
  2. Mail servers without IPv6
    mx1.avonet.cz, spool.avonet.cz have no AAAA record, so mail from IPv6-only servers can't reach them directly. If a provider runs your mail, that's their setting; if you run it, add AAAA records for these hosts.

Check again

ns.avonet.cz  Has IPv6

A (IPv4)217.112.162.34
AAAA (IPv6)2a00:6500:0:11::a

Browsers on dual-stack networks will usually pick IPv6 here (the "Happy Eyeballs" algorithm races both and prefers v6).

Copy the evidence — a citation-ready record of this measurement

 Permanent link: aaaa.bot/r/O2oWVSVX6c · How we measure

Checked 2026-11-15 17:54:47 UTC. Full DNS report: dns.pizza/domain/ns.avonet.cz · Age, certificate and blocklists: how.is/ns.avonet.cz · JSON: /api/v1/ns.avonet.cz