free.de

Checked 21 October 2026, 22:31 UTC · via 8.8.8.8
!Passed with warnings
23 passed 2 warnings 0 failed 4 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.free.de, ns.xs4free.net, ns3.knipp.de, ns5.xs4free.net, robotns2.second-ns.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns.free.de, ns.xs4free.net, ns3.knipp.de, ns5.xs4free.net, robotns2.second-ns.de
NS in the zone
ns.free.de, ns.xs4free.net, ns3.knipp.de, ns5.xs4free.net, robotns2.second-ns.de
NameserverAddressesNetwork (AS)Glue
ns.free.de91.204.6.66AS31371 WISSENSCHAFTSLADEN-AS - Wissenschaftsladen Dortmund e.V., DE91.204.6.66
ns.xs4free.net91.204.4.5AS31371 WISSENSCHAFTSLADEN-AS - Wissenschaftsladen Dortmund e.V., DE-
ns3.knipp.de195.253.113.3 2a01:5b0:31::3AS8391 KNIPP-AS - Knipp Medien und Kommunikation GmbH, DE AS8391 KNIPP-AS - Knipp Medien und Kommunikation GmbH, DE-
ns5.xs4free.net91.204.7.141AS31371 WISSENSCHAFTSLADEN-AS - Wissenschaftsladen Dortmund e.V., DE-
robotns2.second-ns.de213.133.100.103 2a01:4f8:0:1::5ddc:2AS24940 HETZNER-AS - Hetzner Online GmbH, DE AS24940 HETZNER-AS - Hetzner Online GmbH, DE-

Checks

  • ✓ 5 nameservers #6
    Delegated to ns.free.de, ns.xs4free.net, ns3.knipp.de, ns5.xs4free.net, robotns2.second-ns.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: ns.free.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 5 IPv4 /24s and 2 IPv6 /48s.
  • ✓ 3 autonomous systems #11
    The nameservers are spread over: AS24940 (HETZNER-AS - Hetzner Online GmbH, DE): 2 addresses; AS31371 (WISSENSCHAFTSLADEN-AS - Wissenschaftsladen Dortmund e.V., DE): 3 addresses; AS8391 (KNIPP-AS - Knipp Medien und Kommunikation GmbH, DE): 2 addresses.
  • ✓ Nameserver names under 2 TLDs #12
    Nameserver names use the TLDs .de, .net.
  • i
    Partly IPv6
    These nameservers have no IPv6 address: ns.free.de, ns.xs4free.net, ns5.xs4free.net.
    #13

Nameservers

warn

7 of 7 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns.free.de 91.204.6.66NOERROR, 10 ms, authoritativenoyes / yesrefusedunknown
ns.xs4free.net 91.204.4.5NOERROR, 12 ms, authoritativenoyes / yesrefused9.18.48
ns3.knipp.de 195.253.113.3NOERROR, 11 ms, authoritativenoyes / yesrefused-
ns3.knipp.de 2a01:5b0:31::3NOERROR, 11 ms, authoritativenoyes / yesrefused-
ns5.xs4free.net 91.204.7.141NOERROR, 14 ms, authoritativenoyes / yesrefusedNSD 4.7.0
robotns2.second-ns.de 213.133.100.103NOERROR, 3 ms, authoritativenoyes / yesrefused-
robotns2.second-ns.de 2a01:4f8:0:1::5ddc:2NOERROR, 3 ms, authoritativenoyes / yesrefused-

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: ns.xs4free.net: "9.18.48"; ns5.xs4free.net: "NSD 4.7.0". 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 2026100302 · primary ns.free.de

Found

Primary (MNAME)
ns.free.de
Contact (RNAME)
admin.free.de
Serial
2026100302
Refresh / retry
10800 s / 1800 s
Expire
604800 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
ns.free.de (91.204.6.66)2026100302
ns.xs4free.net (91.204.4.5)2026100302
ns3.knipp.de (195.253.113.3)2026100302
ns3.knipp.de (2a01:5b0:31::3)2026100302
ns5.xs4free.net (91.204.7.141)2026100302
robotns2.second-ns.de (213.133.100.103)2026100302
robotns2.second-ns.de (2a01:4f8:0:1::5ddc:2)2026100302

Checks

  • ✓ Serial 2026100302 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 30m, expire 7d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns.free.de is one of the listed nameservers.
  • ✓ Contact admin@free.de #25
    The SOA RNAME admin.free.de means admin@free.de.
  • ✓ Date-based serial #26
    The serial 2026100302 follows the YYYYMMDDnn convention (2026-10-03).

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

9 records at the apex

Found

Read from
91.204.6.66:53
TypeValueTTL
SOAns.free.de. admin.free.de. 2026100302 10800 1800 604800 8640086400
NSns.free.de.86400
NSns5.xs4free.net.86400
NSns3.knipp.de.86400
NSns.xs4free.net.86400
NSrobotns2.second-ns.de.86400
A91.204.6.773600
MX10 pop.free.de.3600
TXT"v=spf1 ip4:91.204.4.0/22 ~all"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 1h, MX 1h, 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