uni-kassel.de

Checked 22 October 2026, 00:50 UTC · via 8.8.8.8
!Passed with warnings
21 passed 1 warning 0 failed 7 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-1.dfn.de, dns-2.dfn.de, dns-3.dfn.de, pm8-3.its.uni-kassel.de, pm8-4.its.uni-kassel.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-1.dfn.de, dns-2.dfn.de, dns-3.dfn.de, pm8-3.its.uni-kassel.de, pm8-4.its.uni-kassel.de
NS in the zone
dns-1.dfn.de, dns-2.dfn.de, dns-3.dfn.de, pm8-3.its.uni-kassel.de, pm8-4.its.uni-kassel.de
NameserverAddressesNetwork (AS)Glue
dns-1.dfn.de193.174.75.50 2001:638:d:b101::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
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-
dns-3.dfn.de193.174.75.58 2001:638:d:b103::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
pm8-3.its.uni-kassel.de141.51.8.3AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE141.51.8.3
pm8-4.its.uni-kassel.de141.51.8.4AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE141.51.8.4

Checks

  • ✓ 5 nameservers #6
    Delegated to dns-1.dfn.de, dns-2.dfn.de, dns-3.dfn.de, pm8-3.its.uni-kassel.de, pm8-4.its.uni-kassel.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: pm8-3.its.uni-kassel.de, pm8-4.its.uni-kassel.de.
  • ✓ All names resolve #9
    Every nameserver name has an address and is not an alias.
  • i
    One address family in one network
    all IPv6 addresses are in 2001:638:d::/48, while the other address family is spread over several networks.
    #10
  • 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
  • i
    Partly IPv6
    These nameservers have no IPv6 address: pm8-3.its.uni-kassel.de, pm8-4.its.uni-kassel.de.
    #13

Nameservers

info

8 of 8 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns-1.dfn.de 193.174.75.50NOERROR, 12 ms, authoritativenoyes / yesrefused0
dns-1.dfn.de 2001:638:d:b101::1NOERROR, 12 ms, authoritativenoyes / yesrefused0
dns-2.dfn.de 193.174.75.54NOERROR, 6 ms, authoritativenoyes / yesrefused0
dns-2.dfn.de 2001:638:d:b102::1NOERROR, 7 ms, authoritativenoyes / yesrefused0
dns-3.dfn.de 193.174.75.58NOERROR, 10 ms, authoritativenoyes / yesrefused0
dns-3.dfn.de 2001:638:d:b103::1NOERROR, 8 ms, authoritativenoyes / yesrefused0
pm8-3.its.uni-kassel.de 141.51.8.3NOERROR, 7 ms, authoritativenoyes / yesrefusedup-to-date
pm8-4.its.uni-kassel.de 141.51.8.4NOERROR, 8 ms, authoritativenoyes / yesrefusedup-to-date

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.
  • i
    Identifying string disclosed
    These nameservers answer version queries with a string that is not a version number: dns-1.dfn.de: "0"; dns-2.dfn.de: "0"; dns-3.dfn.de: "0"; pm8-3.its.uni-kassel.de: "up-to-date"; pm8-4.its.uni-kassel.de: "up-to-date".
    #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 2026102101 · primary pm8-3.its.uni-kassel.de

Found

Primary (MNAME)
pm8-3.its.uni-kassel.de
Contact (RNAME)
netzbetrieb.its.uni-kassel.de
Serial
2026102101
Refresh / retry
28800 s / 7200 s
Expire
2419200 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns-1.dfn.de (193.174.75.50)2026102101
dns-1.dfn.de (2001:638:d:b101::1)2026102101
dns-2.dfn.de (193.174.75.54)2026102101
dns-2.dfn.de (2001:638:d:b102::1)2026102101
dns-3.dfn.de (193.174.75.58)2026102101
dns-3.dfn.de (2001:638:d:b103::1)2026102101
pm8-3.its.uni-kassel.de (141.51.8.3)2026102101
pm8-4.its.uni-kassel.de (141.51.8.4)2026102101

Checks

  • ✓ Serial 2026102101 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 8h, retry 2h, expire 28d, negative TTL 1h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver pm8-3.its.uni-kassel.de is one of the listed nameservers.
  • ✓ Contact netzbetrieb@its.uni-kassel.de #25
    The SOA RNAME netzbetrieb.its.uni-kassel.de means netzbetrieb@its.uni-kassel.de.
  • ✓ Date-based serial #26
    The serial 2026102101 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

pass

30 records at the apex

Found

Read from
193.174.75.50:53
TypeValueTTL
SOApm8-3.its.uni-kassel.de. netzbetrieb.its.uni-kassel.de. 2026102101 28800 7200 2419200 36003600
NSdns-3.dfn.de.3600
NSdns-1.dfn.de.3600
NSpm8-4.its.uni-kassel.de.3600
NSdns-2.dfn.de.3600
NSpm8-3.its.uni-kassel.de.3600
A141.51.95.123600
A141.51.95.133600
MX10 mx3.its.uni-kassel.de.3600
MX10 mx4.its.uni-kassel.de.3600
MX10 mx1.its.uni-kassel.de.3600
MX10 mx2.its.uni-kassel.de.3600
TXT"zone-ownership-verification-fe27a0f7d234137402c57ddab340cf7b251069a0ca55b60d6d5fa90c6618e0b8"3600
TXT"v=spf1 redirect=15777.hosted-spf.de"3600
TXT"MS=ms10518323"3600
TXT"HARICA-NnxXPdKwldlsMQU5ZlA"3600
TXT"mandrill_verify.vVu098Vo5G7IqFdEjikTOQ"3600
TXT"brevo-code:66bd761ccb6e390e88fe796b85163a0a"3600
TXT"domainsecurity-verification=ef7a4997934a397edbc08c0d9b381bc1da2983f9"3600
TXT"ZOOM_verify_z71e1kEXRp-VA7wyUQJNLA"3600
TXT"brevo-code:68a29e7b7e11d73d96dee803ca358ac5"3600
TXT"google-site-verification=oF1-_gMrfrPwxzPzNZE_-AyVzalfIQxx9BGLp69Ku4A"3600
TXT"apple-domain-verification=XnQ1Z5WfEC73Bncs"3600
TXT"sophos-domain-verification=eeb7a35913881b3fd4ec5a8984fb691c41d8f2349af7048a9bfa16549cff9a1d"3600
TXT"adobe-idp-site-verification=b4ec6970fef2eea6bdadecd9328aa18a20f8f017060c127c0f3a6239499bd2d4"3600
TXT"cisco-ci-domain-verification=3dbaae0448e8c8101be72e20a069cbff00300f9cbdd479306655f850abcd78e7"3600
CAA0 issue "sectigo.com"3600
CAA0 iodef "mailto:postmaster@uni-kassel.de"3600
CAA0 issue "harica.gr"3600
CAA0 issue "letsencrypt.org"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 1h, 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.
  • ✓ CAA restricts issuance #35
    Certificates may be issued by: sectigo.com, harica.gr, letsencrypt.org.