aalen.de

.de country-code

Found

TLD

.de (country-code)

ICANN policies apply

no

Checks

• i

  .de is a country-code TLD (ccTLD)

  Country-code TLD: governed by its local registry under national policy, not by an ICANN contract. Registrar accreditation, dispute resolution and RDAP/WHOIS rules are set by the registry.

  #1
• ✓ TLD delegated and signed #2

  .de is delegated in the root zone and DNSSEC-signed.
• i

  Registration data not available

  No registration data via RDAP: the registry of .de offers no RDAP service. Many ccTLD registries don't offer RDAP; check the registry's WHOIS instead.

  #3

auth01.ns.td-fn.net, auth02.ns.td-fn.net

Found

Parent zone

de

Delegation from

a.nic.de (194.0.0.53)

NS at the parent

auth01.ns.td-fn.net, auth02.ns.td-fn.net

NS in the zone

auth01.ns.td-fn.net, auth02.ns.td-fn.net

Checks

• i

  2 nameservers

  Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: auth01.ns.td-fn.net, auth02.ns.td-fn.net.

  #6
• ✓ Parent and zone agree #7

  The parent delegation and the zone's NS records list the same nameservers.
• ✓ No glue needed #8

  All nameservers are outside the zone, so no glue records are needed.
• ✓ All names resolve #9

  Every nameserver name has an address and is not an alias.
• ✓ Nameservers in different networks #10

  The nameservers are spread over 2 IPv4 /24s and 2 IPv6 /48s.
• ✓ 2 autonomous systems #11

  The nameservers are spread over: AS12306 (PLUSLINE - Plus.line AG, DE): 2 addresses; AS21263 (TELEDATA-AS - TeleData GmbH, DE): 2 addresses.
• i

  All nameserver names under .net

  All nameserver names are under one TLD, so a problem with that TLD also makes the nameservers unreachable. Some operators use names under two TLDs for extra resilience.

  #12
• ✓ All reachable over IPv6 #13

  Every nameserver has an IPv6 address.

4 of 4 addresses answer authoritatively

Found

Checks

• ✓ All respond #14

  All 4 nameserver addresses answered.
• ✓ All authoritative #15

  Every responding nameserver answers authoritatively for the zone.
• ✓ No recursion #16

  The nameservers do not answer recursive queries for other domains.
• i

  Identifying string disclosed

  These nameservers answer version queries with a string that is not a version number: auth01.ns.td-fn.net: "[SECURED]"; auth02.ns.td-fn.net: "[SECURED]".

  #17
• ✓ Zone transfers refused #18

  No nameserver allows a zone transfer to the public.
• ✓ TCP supported #19

  All nameservers answer over TCP.
• ✓ EDNS supported #20

  All nameservers support EDNS(0).
• ✓ Public addresses #21

  All nameserver addresses are publicly routable.

serial 2026040102 · primary ans1.arcos.de

Found

Primary (MNAME)

ans1.arcos.de

Contact (RNAME)

hostmaster.arcos.de

Serial

2026040102

Refresh / retry

28800 s / 7200 s

Expire

604800 s

Negative TTL

86400 s

Serial per nameserver

Checks

• ✓ Serial 2026040102 everywhere #22

  All nameservers serve the same version of the zone.
• ✓ Timers within recommendations #23

  SOA refresh 8h, retry 2h, expire 7d, negative TTL 1d.
• i

  Hidden master

  The primary nameserver ans1.arcos.de is not listed as a nameserver: a hidden master that only feeds the public secondaries. That is a common setup; make sure it is not reachable for zone transfers from outside.

  #24
• ✓ Contact hostmaster@arcos.de #25

  The SOA RNAME hostmaster.arcos.de means hostmaster@arcos.de.
• ✓ Date-based serial #26

  The serial 2026040102 follows the YYYYMMDDnn convention (2026-04-01).