hcu-hamburg.de

Checked 21 October 2026, 22:42 UTC · via 8.8.8.8
!Passed with warnings
21 passed 1 warning 0 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

info

dns-2.dfn.de, ns01.hcu-hamburg.de, ns02.hcu-hamburg.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-2.dfn.de, ns01.hcu-hamburg.de, ns02.hcu-hamburg.de
NS in the zone
dns-2.dfn.de, ns01.hcu-hamburg.de, ns02.hcu-hamburg.de
NameserverAddressesNetwork (AS)Glue
dns-2.dfn.de193.174.75.54 2001:638:d:b102::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
ns01.hcu-hamburg.de194.95.77.71AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE194.95.77.71
ns02.hcu-hamburg.de194.95.77.72AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE194.95.77.72

Checks

  • ✓ 3 nameservers #6
    Delegated to dns-2.dfn.de, ns01.hcu-hamburg.de, ns02.hcu-hamburg.de.
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • ✓ Glue present and correct #8
    Glue is published for the nameservers inside the zone: ns01.hcu-hamburg.de, ns02.hcu-hamburg.de.
  • ✓ 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): 4 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: ns01.hcu-hamburg.de, ns02.hcu-hamburg.de.
    #13

Nameservers

info

4 of 4 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns-2.dfn.de 193.174.75.54NOERROR, 7 ms, authoritativenoyes / yesrefused0
dns-2.dfn.de 2001:638:d:b102::1NOERROR, 7 ms, authoritativenoyes / yesrefused0
ns01.hcu-hamburg.de 194.95.77.71NOERROR, 12 ms, authoritativenoyes / yesrefused-
ns02.hcu-hamburg.de 194.95.77.72NOERROR, 23 ms, authoritativenoyes / yesrefused-

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: dns-2.dfn.de: "0".
    #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.

SOA

pass

serial 2032001262 · primary ns01.hcu-hamburg.de

Found

Primary (MNAME)
ns01.hcu-hamburg.de
Contact (RNAME)
it-support.hcu-hamburg.de
Serial
2032001262
Refresh / retry
21600 s / 3600 s
Expire
1209600 s
Negative TTL
600 s

Serial per nameserver

NameserverSerial
dns-2.dfn.de (193.174.75.54)2032001262
dns-2.dfn.de (2001:638:d:b102::1)2032001262
ns01.hcu-hamburg.de (194.95.77.71)2032001262
ns02.hcu-hamburg.de (194.95.77.72)2032001262

Checks

  • ✓ Serial 2032001262 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 6h, retry 1h, expire 14d, negative TTL 10m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns01.hcu-hamburg.de is one of the listed nameservers.
  • ✓ Contact it-support@hcu-hamburg.de #25
    The SOA RNAME it-support.hcu-hamburg.de means it-support@hcu-hamburg.de.
  • ✓ Timestamp serial #26
    The serial 2032001262 is a Unix timestamp (2034-05-23 12:47 UTC).

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

14 records at the apex

Found

Read from
193.174.75.54:53
TypeValueTTL
SOAns01.hcu-hamburg.de. it-support.hcu-hamburg.de. 2032001262 21600 3600 1209600 600600
NSns01.hcu-hamburg.de.600
NSdns-2.dfn.de.600
NSns02.hcu-hamburg.de.600
MX15 smtp5.rz.tu-harburg.de.3600
MX25 smtp3.rz.tu-harburg.de.3600
MX5 smtp4.rz.tu-harburg.de.3600
TXT"apple-domain-verification=t2uHFo2blutLd9CG"3600
TXT"HARICA-UTY1bKvgY6IKnj5WU0J"3600
TXT"MS=ms96064425"3600
TXT"ZOOM_verify_SO5dw5x3SuWSW8hlDjcYtQ"3600
TXT"autodesk-domain-verification=KvPChatKcrqwYxseMsbf"3600
TXT"adobe-idp-site-verification=b9b1a330e0b66eeb8587693dff9db2ca2e9b56f3affa3079969667e0ec9e60fe"3600
TXT"v=spf1 a:mailgate01.hcuhh.de a:mailgate02.hcuhh.de include:_spf.tu-harburg.de include:spf.protection.outlook.com ~all"3600

Checks

  • ✓ TTLs within range #32
    TTLs: MX 1h, NS 10m. The NS TTL at the parent is 1d and in the zone 10m; resolvers may use either.
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • ✓ No wildcard #34
    Names that don't exist return NXDOMAIN.
  • 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