ddb.de

Checked 21 October 2026, 22:12 UTC · via 8.8.8.8
!Passed with warnings
22 passed 1 warning 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

deneb.dfn.de, dns1.fiz-karlsruhe.de, dns2.fiz-karlsruhe.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
deneb.dfn.de, dns1.fiz-karlsruhe.de, dns2.fiz-karlsruhe.de
NS in the zone
deneb.dfn.de, dns1.fiz-karlsruhe.de, dns2.fiz-karlsruhe.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-
dns1.fiz-karlsruhe.de141.66.18.17AS13040 ASN-FIZ - FIZ Karlsruhe - Leibniz-Institut fuer Informationsinfrastruktur GmbH, DE141.66.18.17
dns2.fiz-karlsruhe.de141.66.19.17AS13040 ASN-FIZ - FIZ Karlsruhe - Leibniz-Institut fuer Informationsinfrastruktur GmbH, DE141.66.19.17

Checks

  • ✓ 3 nameservers #6
    Delegated to deneb.dfn.de, dns1.fiz-karlsruhe.de, dns2.fiz-karlsruhe.de.
  • ✓ 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 3 IPv4 /24s and 1 IPv6 /48.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS13040 (ASN-FIZ - FIZ Karlsruhe - Leibniz-Institut fuer Informationsinfrastruktur GmbH, DE): 2 addresses; AS680 (DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., 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: dns1.fiz-karlsruhe.de, dns2.fiz-karlsruhe.de.
    #13

Nameservers

info

4 of 4 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
dns1.fiz-karlsruhe.de 141.66.18.17NOERROR, 6 ms, authoritativenoyes / yesrefused-
dns2.fiz-karlsruhe.de 141.66.19.17NOERROR, 6 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: deneb.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 409 · primary dns1.fiz-karlsruhe.de

Found

Primary (MNAME)
dns1.fiz-karlsruhe.de
Contact (RNAME)
hostmaster.fiz-karlsruhe.de
Serial
409
Refresh / retry
10800 s / 3600 s
Expire
2332800 s
Negative TTL
900 s

Serial per nameserver

NameserverSerial
deneb.dfn.de (192.76.176.9)409
deneb.dfn.de (2001:638:800:1::9)409
dns1.fiz-karlsruhe.de (141.66.18.17)409
dns2.fiz-karlsruhe.de (141.66.19.17)409

Checks

  • ✓ Serial 409 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 27d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns1.fiz-karlsruhe.de is one of the listed nameservers.
  • ✓ Contact hostmaster@fiz-karlsruhe.de #25
    The SOA RNAME hostmaster.fiz-karlsruhe.de means hostmaster@fiz-karlsruhe.de.
  • ✓ Counter serial #26
    The serial 409 is a plain counter.

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
192.76.176.9:53
TypeValueTTL
SOAdns1.fiz-karlsruhe.de. hostmaster.fiz-karlsruhe.de. 409 10800 3600 2332800 90028800
NSdns2.fiz-karlsruhe.de.28800
NSdns1.fiz-karlsruhe.de.28800
NSdeneb.dfn.de.28800
A141.66.192.6228800
MX10 mx20.system-hoster.com.28800
MX10 mx21.system-hoster.com.28800
TXT"HARICA-QC0CtYjmxaO0FJkWptt"28800
TXT"v=spf1 a mx include:spf.system-hoster.com -all"28800

Checks

  • ✓ TTLs within range #32
    TTLs: A 8h, MX 8h, NS 8h. The NS TTL at the parent is 1d and in the zone 8h; 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