gdw-berlin.de

Checked 21 October 2026, 22:32 UTC · via 8.8.8.8
!Passed with warnings
21 passed 2 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

info

ns.ipn.de, ns.link-m.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns.ipn.de, ns.link-m.de
NS in the zone
ns.ipn.de, ns.link-m.de
NameserverAddressesNetwork (AS)Glue
ns.ipn.de193.96.188.100AS702 UUNET - Verizon Business, US-
ns.link-m.de82.135.8.2 2001:a60:901e::2AS8767 MNET-AS - M-net Telekommunikations GmbH, DE AS8767 MNET-AS - M-net Telekommunikations GmbH, DE82.135.8.2 2001:a60:901e::2

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns.ipn.de, ns.link-m.de.
    #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 1 IPv6 /48.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS702 (UUNET - Verizon Business, US): 1 address; AS8767 (MNET-AS - M-net Telekommunikations GmbH, DE): 2 addresses.
  • 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: ns.ipn.de.
    #13

Nameservers

warn

3 of 3 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns.ipn.de 193.96.188.100NOERROR, 10 ms, authoritativenoyes / yesrefused9.9.5-9+deb8u19-Debian
ns.link-m.de 82.135.8.2NOERROR, 6 ms, authoritativenoyes / yesrefused9.18.30-0ubuntu0.20.04.2-Ubuntu
ns.link-m.de 2001:a60:901e::2NOERROR, 10 ms, authoritativenoyes / yesrefused9.18.30-0ubuntu0.20.04.2-Ubuntu

Checks

  • ✓ All respond #14
    All 3 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: ns.ipn.de: "9.9.5-9+deb8u19-Debian"; ns.link-m.de: "9.18.30-0ubuntu0.20.04.2-Ubuntu". 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 2026032002 · primary ns.ipn.de

Found

Primary (MNAME)
ns.ipn.de
Contact (RNAME)
support.ipn-b.de
Serial
2026032002
Refresh / retry
10800 s / 3600 s
Expire
604800 s
Negative TTL
43200 s

Serial per nameserver

NameserverSerial
ns.ipn.de (193.96.188.100)2026032002
ns.link-m.de (82.135.8.2)2026032002
ns.link-m.de (2001:a60:901e::2)2026032002

Checks

  • ✓ Serial 2026032002 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 7d, negative TTL 12h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns.ipn.de is one of the listed nameservers.
  • ✓ Contact support@ipn-b.de #25
    The SOA RNAME support.ipn-b.de means support@ipn-b.de.
  • ✓ Date-based serial #26
    The serial 2026032002 follows the YYYYMMDDnn convention (2026-03-20).

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

8 records at the apex

Found

Read from
193.96.188.100:53
TypeValueTTL
SOAns.ipn.de. support.ipn-b.de. 2026032002 10800 3600 604800 432003600
NSns.ipn.de.3600
NSns.link-m.de.3600
A193.96.188.221300
MX20 mx02.hornetsecurity.com.3600
MX10 mx01.hornetsecurity.com.3600
TXT"94c4865983a7e7601637540b2312935e12e843968e78f1b351fcb29f0bec1bc8"3600
TXT"v=spf1 include:spf.hornetsecurity.com ip4:193.96.188.0/24 ip4:157.90.122.239 ~all"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, MX 1h, NS 1h. The NS TTL at the parent is 1d and in the zone 1h; 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