thuenen.de

Checked 22 October 2026, 00:40 UTC · via 8.8.8.8
✗Problems found
18 passed 3 warnings 1 failed 7 info

Registration

info

.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

Delegation

warn

deneb.dfn.de, fermat.it.vti.bund.de, zuse.it.vti.bund.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
deneb.dfn.de, fermat.it.vti.bund.de, zuse.it.vti.bund.de
NS in the zone
deneb.dfn.de, fermat.thuenen.de, zuse.thuenen.de
NameserverAddressesNetwork (AS)Glue
deneb.dfn.de192.76.176.9 2001:638:800:1::9AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
fermat.it.vti.bund.de (parent only)134.110.5.32AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
fermat.thuenen.de (zone only)134.110.5.32AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
zuse.it.vti.bund.de (parent only)134.110.5.10AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
zuse.thuenen.de (zone only)134.110.5.10AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-

Checks

  • ✓ 3 nameservers #6
    Delegated to deneb.dfn.de, fermat.it.vti.bund.de, zuse.it.vti.bund.de.
  • !
    NS sets differ
    The nameservers at the parent and in the zone should be the same. Only at the parent: fermat.it.vti.bund.de, zuse.it.vti.bund.de; only in the zone: fermat.thuenen.de, zuse.thuenen.de. deneb.dfn.de, fermat.it.vti.bund.de, fermat.thuenen.de, zuse.it.vti.bund.de, zuse.thuenen.de report NS deneb.dfn.de fermat.thuenen.de zuse.thuenen.de.
    #7
  • ✓ 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 1 IPv6 /48.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS680 (DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE): 6 addresses). An outage or attack on that network affects all nameservers; large anycast providers mitigate this, but a secondary DNS provider adds independence.
    #11
  • i
    All nameserver names under .de
    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
  • i
    Partly IPv6
    These nameservers have no IPv6 address: fermat.it.vti.bund.de, fermat.thuenen.de, zuse.it.vti.bund.de, zuse.thuenen.de.
    #13

Nameservers

fail

6 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
deneb.dfn.de 192.76.176.9NOERROR, 14 ms, authoritativenoyes / yesrefused0
deneb.dfn.de 2001:638:800:1::9NOERROR, 14 ms, authoritativenoyes / yesrefused0
fermat.it.vti.bund.de 134.110.5.32NOERROR, 15 ms, authoritativenoyes / yesALLOWED (280 records)9.18.39-0ubuntu0.24.04.8-Ubuntu
fermat.thuenen.de 134.110.5.32NOERROR, 15 ms, authoritativenoyes / yesALLOWED (280 records)9.18.39-0ubuntu0.24.04.8-Ubuntu
zuse.it.vti.bund.de 134.110.5.10NOERROR, 22 ms, authoritativenoyes / yesALLOWED (280 records)9.18.39-0ubuntu0.24.04.8-Ubuntu
zuse.thuenen.de 134.110.5.10NOERROR, 14 ms, authoritativenoyes / yesALLOWED (280 records)9.18.39-0ubuntu0.24.04.8-Ubuntu

Checks

  • ✓ All respond #14
    All 6 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.
  • !
    Software version disclosed
    These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: fermat.it.vti.bund.de: "9.18.39-0ubuntu0.24.04.8-Ubuntu"; fermat.thuenen.de: "9.18.39-0ubuntu0.24.04.8-Ubuntu"; zuse.it.vti.bund.de: "9.18.39-0ubuntu0.24.04.8-Ubuntu"; zuse.thuenen.de: "9.18.39-0ubuntu0.24.04.8-Ubuntu". Hide or replace the version string.
    #17
  • ✗
    Zone transfer allowed
    These nameservers send the complete zone to anyone who asks (AXFR), exposing all host names: fermat.it.vti.bund.de (134.110.5.32): 280 records; fermat.thuenen.de (134.110.5.32): 280 records; zuse.it.vti.bund.de (134.110.5.10): 280 records; zuse.thuenen.de (134.110.5.10): 280 records. Restrict zone transfers to your secondary servers.
    #18
  • ✓ 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.

SOA

pass

serial 2026090201 · primary fermat.thuenen.de

Found

Primary (MNAME)
fermat.thuenen.de
Contact (RNAME)
hostmaster.thuenen.de
Serial
2026090201
Refresh / retry
14400 s / 3600 s
Expire
1209600 s
Negative TTL
900 s

Serial per nameserver

NameserverSerial
deneb.dfn.de (192.76.176.9)2026090201
deneb.dfn.de (2001:638:800:1::9)2026090201
fermat.it.vti.bund.de (134.110.5.32)2026090201
fermat.thuenen.de (134.110.5.32)2026090201
zuse.it.vti.bund.de (134.110.5.10)2026090201
zuse.thuenen.de (134.110.5.10)2026090201

Checks

  • ✓ Serial 2026090201 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 4h, retry 1h, expire 14d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver fermat.thuenen.de is one of the listed nameservers.
  • ✓ Contact hostmaster@thuenen.de #25
    The SOA RNAME hostmaster.thuenen.de means hostmaster@thuenen.de.
  • ✓ Date-based serial #26
    The serial 2026090201 follows the YYYYMMDDnn convention (2026-09-02).

DNSSEC

warn

Not signed

Found

Validated by resolver
no

Checks

  • !
    Not signed
    The zone is not signed with DNSSEC, so answers can be spoofed. Enable DNSSEC at your DNS provider and publish the DS record at your registrar.
    #27

Records

info

13 records at the apex

Found

Read from
192.76.176.9:53
TypeValueTTL
SOAfermat.thuenen.de. hostmaster.thuenen.de. 2026090201 14400 3600 1209600 90043200
NSfermat.thuenen.de.43200
NSdeneb.dfn.de.43200
NSzuse.thuenen.de.43200
A134.110.3.4300
MX10 a1481.mx.srv.dfn.de.43200
MX10 b1481.mx.srv.dfn.de.43200
MX10 c1481.mx.srv.dfn.de.43200
TXT"HARICA-4fUlQgkXLOi6mqceHbM"43200
TXT"cisco-ci-domain-verification=2494317d8379463eb0ab8a84a2539c6c6ecf56c4cf9beb27467a17b348017245"43200
TXT"v=spf1 mx ip4:134.110.0.35 ip4:134.110.0.52 -all"43200
TXT"apple-domain-verification=iGqs668GMnVbBtYm"43200
TXT"MS=45194C77B7726D6698148312401B1B314042D12B"43200

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, MX 12h, NS 12h. The NS TTL at the parent is 1d and in the zone 12h; resolvers may use either.
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • i
    Wildcard record
    A random name under the zone resolves, so there is a wildcard (*) record. Typos and non-existent hosts resolve too, which can confuse mail and certificate checks.
    #34
  • i
    No CAA records
    Without CAA records any certificate authority may issue certificates for this domain. A CAA record limits issuance to the CAs you use.
    #35