uni-kiel.de

Checked 22 October 2026, 00:50 UTC · via 8.8.8.8
!Passed with warnings
22 passed 2 warnings 0 failed 5 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, ns1.rz.uni-kiel.de, ns2.rz.uni-kiel.de, ns3.rz.uni-kiel.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-2.dfn.de, ns1.rz.uni-kiel.de, ns2.rz.uni-kiel.de, ns3.rz.uni-kiel.de
NS in the zone
dns-2.dfn.de, ns1.rz.uni-kiel.de, ns2.rz.uni-kiel.de, ns3.rz.uni-kiel.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-
ns1.rz.uni-kiel.de134.245.10.7 2a0a:6200:0:1::ff01AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE134.245.10.7 2a0a:6200:0:1::ff01
ns2.rz.uni-kiel.de134.245.1.36 2a0a:6200:0:1::ff02AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE134.245.1.36 2a0a:6200:0:1::ff02
ns3.rz.uni-kiel.de134.245.1.2 2a0a:6200:0:1::ff03AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE134.245.1.2 2a0a:6200:0:1::ff03

Checks

  • ✓ 4 nameservers #6
    Delegated to dns-2.dfn.de, ns1.rz.uni-kiel.de, ns2.rz.uni-kiel.de, ns3.rz.uni-kiel.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: ns1.rz.uni-kiel.de, ns2.rz.uni-kiel.de, ns3.rz.uni-kiel.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 3 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): 8 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
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

warn

8 of 8 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
ns1.rz.uni-kiel.de 134.245.10.7NOERROR, 17 ms, authoritativenoyes / yesrefusednot currently available
ns1.rz.uni-kiel.de 2a0a:6200:0:1::ff01NOERROR, 21 ms, authoritativenoyes / yesrefusednot currently available
ns2.rz.uni-kiel.de 134.245.1.36NOERROR, 14 ms, authoritativenoyes / yesrefused9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16
ns2.rz.uni-kiel.de 2a0a:6200:0:1::ff02NOERROR, 17 ms, authoritativenoyes / yesrefused9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16
ns3.rz.uni-kiel.de 134.245.1.2NOERROR, 17 ms, authoritativenoyes / yesrefused9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16
ns3.rz.uni-kiel.de 2a0a:6200:0:1::ff03NOERROR, 15 ms, authoritativenoyes / yesrefused9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16

Checks

  • ✓ All respond #14
    All 8 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: ns2.rz.uni-kiel.de: "9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16"; ns3.rz.uni-kiel.de: "9.11.4-P2-RedHat-9.11.4-26.P2.el7_9.16". 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 2026102103 · primary ns1.rz.uni-kiel.de

Found

Primary (MNAME)
ns1.rz.uni-kiel.de
Contact (RNAME)
dns.rz.uni-kiel.de
Serial
2026102103
Refresh / retry
21600 s / 3600 s
Expire
1209600 s
Negative TTL
10800 s

Serial per nameserver

NameserverSerial
dns-2.dfn.de (193.174.75.54)2026102103
dns-2.dfn.de (2001:638:d:b102::1)2026102103
ns1.rz.uni-kiel.de (134.245.10.7)2026102103
ns1.rz.uni-kiel.de (2a0a:6200:0:1::ff01)2026102103
ns2.rz.uni-kiel.de (134.245.1.36)2026102103
ns2.rz.uni-kiel.de (2a0a:6200:0:1::ff02)2026102103
ns3.rz.uni-kiel.de (134.245.1.2)2026102103
ns3.rz.uni-kiel.de (2a0a:6200:0:1::ff03)2026102103

Checks

  • ✓ Serial 2026102103 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 6h, retry 1h, expire 14d, negative TTL 3h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.rz.uni-kiel.de is one of the listed nameservers.
  • ✓ Contact dns@rz.uni-kiel.de #25
    The SOA RNAME dns.rz.uni-kiel.de means dns@rz.uni-kiel.de.
  • ✓ Date-based serial #26
    The serial 2026102103 follows the YYYYMMDDnn convention (2026-10-21).

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

19 records at the apex

Found

Read from
193.174.75.54:53
TypeValueTTL
SOAns1.rz.uni-kiel.de. dns.rz.uni-kiel.de. 2026102103 21600 3600 1209600 10800172800
NSns1.rz.uni-kiel.de.172800
NSns3.rz.uni-kiel.de.172800
NSns2.rz.uni-kiel.de.172800
NSdns-2.dfn.de.172800
A134.245.13.20172800
A134.245.13.22172800
A134.245.13.21172800
A134.245.13.23172800
MX100 c2002.mx.srv.dfn.de.172800
MX100 b2002.mx.srv.dfn.de.172800
MX100 a2002.mx.srv.dfn.de.172800
TXT"knowbe4-site-verification=17b2bc429a503da323817dd943241885"172800
TXT"google-site-verification=x6ArbUEGD4dPrSp99gu3whQTGwDKCxgR98sxiTsjNIg"172800
TXT"google-site-verification=fwz5NPUIpYsX732zzqAO3Jui8oBZdWUcVoeXePTGIlQ"172800
TXT"google-site-verification=RgWe9Ayfd8l2m8ONxe95vAKa-9PgMA4lSWI1vxmHEY8"172800
TXT"v=spf1 include:_spf.uni-kiel.de ~all"172800
TXT"MS=ms56737101"172800
TXT"adobe-idp-site-verification=83a2621aa65d83d7904abc4623d1cd78f6d01dab5296bee39e17ba5c1d8120ca"172800

Checks

  • ✓ TTLs within range #32
    TTLs: A 2d, MX 2d, NS 2d. The NS TTL at the parent is 1d and in the zone 2d; 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