hs-bremerhaven.de

Checked 21 October 2026, 22:51 UTC · via 8.8.8.8
!Passed with warnings
20 passed 3 warnings 0 failed 6 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, netu1.awi.de, ns1.hs-bremerhaven.de, ns2.hs-bremerhaven.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
deneb.dfn.de, netu1.awi.de, ns1.hs-bremerhaven.de, ns2.hs-bremerhaven.de
NS in the zone
deneb.dfn.de, netu1.awi.de, ns1.hs-bremerhaven.de, ns2.hs-bremerhaven.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-
netu1.awi.de134.1.2.251AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE134.1.2.251
ns1.hs-bremerhaven.de192.109.135.75 2001:638:706:508::75AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE192.109.135.75 2001:638:706:504::75
ns2.hs-bremerhaven.de195.37.49.161 2001:638:706:506::161AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE195.37.49.161 2001:638:706:506::161

Checks

  • ✓ 4 nameservers #6
    Delegated to deneb.dfn.de, netu1.awi.de, ns1.hs-bremerhaven.de, ns2.hs-bremerhaven.de.
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • !
    Glue differs from the zone
    The addresses at the parent (glue) differ from the addresses in the zone: ns1.hs-bremerhaven.de (glue 192.109.135.75, 2001:638:706:504::75, zone 192.109.135.75, 2001:638:706:508::75). Update the glue at your registrar.
    #8
  • ✓ 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 4 IPv4 /24s and 2 IPv6 /48s.
  • 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): 7 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: netu1.awi.de.
    #13

Nameservers

warn

7 of 7 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
netu1.awi.de 134.1.2.251NOERROR, 15 ms, authoritativenoyes / yesrefused9.18.39-0ubuntu0.22.04.7-Ubuntu
ns1.hs-bremerhaven.de 192.109.135.75NOERROR, 15 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.9.17 (built Aug 5 2026 13:27:37 by root@localhost)
ns1.hs-bremerhaven.de 2001:638:706:508::75NOERROR, 15 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.9.17 (built Aug 5 2026 13:27:37 by root@localhost)
ns2.hs-bremerhaven.de 195.37.49.161NOERROR, 15 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.9.17 (built Aug 5 2026 13:27:37 by root@localhost)
ns2.hs-bremerhaven.de 2001:638:706:506::161NOERROR, 15 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.9.17 (built Aug 5 2026 13:27:37 by root@localhost)

Checks

  • ✓ All respond #14
    All 7 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: netu1.awi.de: "9.18.39-0ubuntu0.22.04.7-Ubuntu"; ns1.hs-bremerhaven.de: "PowerDNS Authoritative Server 4.9.17 (built Aug 5 2026 13:27:37 by root@localhost)"; ns2.hs-bremerhaven.de: "PowerDNS Authoritative Server 4.9.17 (built Aug 5 2026 13:27:37 by root@localhost)". Hide or replace the version string.
    #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 2026454759 · primary ns1.hs-bremerhaven.de

Found

Primary (MNAME)
ns1.hs-bremerhaven.de
Contact (RNAME)
fbehrens.hs-bremerhaven.de
Serial
2026454759
Refresh / retry
14400 s / 3600 s
Expire
1209600 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
deneb.dfn.de (192.76.176.9)2026454759
deneb.dfn.de (2001:638:800:1::9)2026454759
netu1.awi.de (134.1.2.251)2026454759
ns1.hs-bremerhaven.de (192.109.135.75)2026454759
ns1.hs-bremerhaven.de (2001:638:706:508::75)2026454759
ns2.hs-bremerhaven.de (195.37.49.161)2026454759
ns2.hs-bremerhaven.de (2001:638:706:506::161)2026454759

Checks

  • ✓ Serial 2026454759 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 4h, retry 1h, expire 14d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.hs-bremerhaven.de is one of the listed nameservers.
  • ✓ Contact fbehrens@hs-bremerhaven.de #25
    The SOA RNAME fbehrens.hs-bremerhaven.de means fbehrens@hs-bremerhaven.de.
  • ✓ Timestamp serial #26
    The serial 2026454759 is a Unix timestamp (2034-03-20 08:05 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

16 records at the apex

Found

Read from
192.76.176.9:53
TypeValueTTL
SOAns1.hs-bremerhaven.de. fbehrens.hs-bremerhaven.de. 2026454759 14400 3600 1209600 8640086400
NSnetu1.awi.de.86400
NSns1.hs-bremerhaven.de.86400
NSns2.hs-bremerhaven.de.86400
NSdeneb.dfn.de.86400
A192.109.135.5086400
AAAA2001:638:706:508::5086400
MX10 a2981.mx.srv.dfn.de.1200
MX10 c2981.mx.srv.dfn.de.1200
MX10 b2981.mx.srv.dfn.de.1200
TXT"MS=ms38758922"3600
TXT"google-site-verification=NMHa_VmqCgGeDX3640bs36bhO_giALvm-R8W72-I7aI"3600
TXT"-" "4fl-rb1-26d"3600
TXT"adobe-idp-site-verification=105ae201644e33c44854a8ecf8fa5e984da8d9faec4d6cfb359d13ac6f2fb42b"3600
TXT"v=spf1 a:smtp.hs-bremerhaven.de a:smtp1.hs-bremerhaven.de a:smtp3.hs-bremerhaven.de a:smtpgw.hs-bremerhaven.de a:pmg.hs-bremerhaven.de a:imap.hs-bremerhaven.de mx include:_spf.zimpel.de include:spf.protection.outlook.com -all"3600
TXT"MS=ms64698491"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 1d, AAAA 1d, MX 20m, NS 1d.
  • ✓ 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