uni-frankfurt.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

warn

chaplin.rz.uni-frankfurt.de, dns-2.dfn.de, wattdenn.rz.uni-frankfurt.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
chaplin.rz.uni-frankfurt.de, dns-2.dfn.de, wattdenn.rz.uni-frankfurt.de
NS in the zone
chaplin.rz.uni-frankfurt.de, dns-2.dfn.de, wattdenn.rz.uni-frankfurt.de
NameserverAddressesNetwork (AS)Glue
chaplin.rz.uni-frankfurt.de141.2.22.74 2001:a38:1001:3109::42AS20633 UNIFFM-NET - Johann Wolfgang Goethe-Universitat Frankfurt am Main, DE AS20633 UNIFFM-NET - Johann Wolfgang Goethe-Universitat Frankfurt am Main, DE141.2.22.74
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-
wattdenn.rz.uni-frankfurt.de141.2.149.10 2001:a38:1001:3110::42AS20633 UNIFFM-NET - Johann Wolfgang Goethe-Universitat Frankfurt am Main, DE AS20633 UNIFFM-NET - Johann Wolfgang Goethe-Universitat Frankfurt am Main, DE141.2.149.10

Checks

  • ✓ 3 nameservers #6
    Delegated to chaplin.rz.uni-frankfurt.de, dns-2.dfn.de, wattdenn.rz.uni-frankfurt.de.
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • !
    Glue differs from the zone
    The addresses at the parent (glue) differ from the addresses in the zone: chaplin.rz.uni-frankfurt.de (glue 141.2.22.74, zone 141.2.22.74, 2001:a38:1001:3109::42); wattdenn.rz.uni-frankfurt.de (glue 141.2.149.10, zone 141.2.149.10, 2001:a38:1001:3110::42). Update the glue at your registrar.
    #8
  • ✓ 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.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS20633 (UNIFFM-NET - Johann Wolfgang Goethe-Universitat Frankfurt am Main, DE): 4 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
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

info

6 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
chaplin.rz.uni-frankfurt.de 141.2.22.74NOERROR, 4 ms, authoritativenoyes / yesrefusedUni Frankfurt DNS [Chaplin]
chaplin.rz.uni-frankfurt.de 2001:a38:1001:3109::42NOERROR, 4 ms, authoritativenoyes / yesrefusedUni Frankfurt DNS [Chaplin]
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
wattdenn.rz.uni-frankfurt.de 141.2.149.10NOERROR, 4 ms, authoritativenoyes / yesrefusedUni Frankfurt DNS [Wattdenn]
wattdenn.rz.uni-frankfurt.de 2001:a38:1001:3110::42NOERROR, 4 ms, authoritativenoyes / yesrefusedUni Frankfurt DNS [Wattdenn]

Checks

  • ✓ All respond #14
    All 6 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: chaplin.rz.uni-frankfurt.de: "Uni Frankfurt DNS [Chaplin]"; dns-2.dfn.de: "0"; wattdenn.rz.uni-frankfurt.de: "Uni Frankfurt DNS [Wattdenn]".
    #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 2026101202 · primary chaplin.rz.uni-frankfurt.de

Found

Primary (MNAME)
chaplin.rz.uni-frankfurt.de
Contact (RNAME)
nameservice.uni-frankfurt.de
Serial
2026101202
Refresh / retry
10000 s / 3600 s
Expire
2419200 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
chaplin.rz.uni-frankfurt.de (141.2.22.74)2026101202
chaplin.rz.uni-frankfurt.de (2001:a38:1001:3109::42)2026101202
dns-2.dfn.de (193.174.75.54)2026101202
dns-2.dfn.de (2001:638:d:b102::1)2026101202
wattdenn.rz.uni-frankfurt.de (141.2.149.10)2026101202
wattdenn.rz.uni-frankfurt.de (2001:a38:1001:3110::42)2026101202

Checks

  • ✓ Serial 2026101202 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 2h46m40s, retry 1h, expire 28d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver chaplin.rz.uni-frankfurt.de is one of the listed nameservers.
  • ✓ Contact nameservice@uni-frankfurt.de #25
    The SOA RNAME nameservice.uni-frankfurt.de means nameservice@uni-frankfurt.de.
  • ✓ Date-based serial #26
    The serial 2026101202 follows the YYYYMMDDnn convention (2026-10-12).

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

14 records at the apex

Found

Read from
141.2.22.74:53
TypeValueTTL
SOAchaplin.rz.uni-frankfurt.de. nameservice.uni-frankfurt.de. 2026101202 10000 3600 2419200 8640038400
NSchaplin.rz.uni-frankfurt.de.38400
NSwattdenn.rz.uni-frankfurt.de.38400
NSdns-2.dfn.de.38400
A141.2.37.19838400
MX20 mx2.uni-frankfurt.de.38400
MX10 mx1.uni-frankfurt.de.38400
TXT"apple-domain-verification=9O2ElvMkcA9WIJxP"38400
TXT"HARICA-APLKyWHAseaCILpKTQL"38400
TXT"google-site-verification=3WUA-2rxt3AaRAdON0eQ9BDKjIKZWNEPTz0oJiq5ncE"38400
TXT"v=spf1 ip4:141.2.22.115 ip4:141.2.22.185 ip4:141.2.22.204 ip4:141.2.22.205 ip4:141.2.22.206 ip4:141.2.22.231 ip4:141.2.22.232 ip4:141.2.22.233 ip4:141.2.22.92 ip4:141.2.22.192 ip4:141.2.42.47 include:spf.protection.outlook.com -all"38400
TXT"MS=75E101694B17E7B7770B961A129D1C7E9D592778"38400
TXT"adobe-idp-site-verification=2bfe06eace1bc6cc8672ddc8b4c18c5ea775c59772d31774d04a7d43c97efbe6"38400
TXT"docusign=428867fb-dc41-4edf-88df-bdcf41a0dca0"38400

Checks

  • ✓ TTLs within range #32
    TTLs: A 640m, MX 640m, NS 640m. The NS TTL at the parent is 1d and in the zone 640m; 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