uni-konstanz.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

dns3.uni-konstanz.de, ns3.uni-konstanz.de, ns4.uni-konstanz.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns3.uni-konstanz.de, ns3.uni-konstanz.de, ns4.uni-konstanz.de
NS in the zone
dns3.uni-konstanz.de, ns3.uni-konstanz.de, ns4.uni-konstanz.de
NameserverAddressesNetwork (AS)Glue
dns3.uni-konstanz.de141.37.18.100 2001:7c0:5f0:f504::18:100AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE141.37.18.100 2001:7c0:5f0:f504::18:100
ns3.uni-konstanz.de134.34.242.3 2001:7c0:2880:2010::31:3AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE134.34.242.3 2001:7c0:2880:2010::31:3
ns4.uni-konstanz.de134.34.242.4 2001:7c0:2880:2010::31:4AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE134.34.242.4 2001:7c0:2880:2010::31:4

Checks

  • ✓ 3 nameservers #6
    Delegated to dns3.uni-konstanz.de, ns3.uni-konstanz.de, ns4.uni-konstanz.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: dns3.uni-konstanz.de, ns3.uni-konstanz.de, ns4.uni-konstanz.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 2 IPv4 /24s and 2 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS553 (BELWUE - Universitaet Stuttgart, DE): 6 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

6 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns3.uni-konstanz.de 141.37.18.100NOERROR, 13 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.9.17
dns3.uni-konstanz.de 2001:7c0:5f0:f504::18:100NOERROR, 14 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.9.17
ns3.uni-konstanz.de 134.34.242.3NOERROR, 10 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 5.1.0-alpha1.380.master.geee030317 (built Apr 22 2026 10:41:37 by root@localhost)
ns3.uni-konstanz.de 2001:7c0:2880:2010::31:3NOERROR, 13 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 5.1.0-alpha1.380.master.geee030317 (built Apr 22 2026 10:41:37 by root@localhost)
ns4.uni-konstanz.de 134.34.242.4NOERROR, 10 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 5.1.0-alpha1.380.master.geee030317 (built Apr 22 2026 10:41:37 by root@localhost)
ns4.uni-konstanz.de 2001:7c0:2880:2010::31:4NOERROR, 12 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 5.1.0-alpha1.380.master.geee030317 (built Apr 22 2026 10:41:37 by root@localhost)

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.
  • !
    Software version disclosed
    These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: dns3.uni-konstanz.de: "PowerDNS Authoritative Server 4.9.17"; ns3.uni-konstanz.de: "PowerDNS Authoritative Server 5.1.0-alpha1.380.master.geee030317 (built Apr 22 2026 10:41:37 by root@localhost)"; ns4.uni-konstanz.de: "PowerDNS Authoritative Server 5.1.0-alpha1.380.master.geee030317 (built Apr 22 2026 10:41:37 by root@localhost)". 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 803036655 · primary ns3.uni-konstanz.de

Found

Primary (MNAME)
ns3.uni-konstanz.de
Contact (RNAME)
hostmaster.uni-konstanz.de
Serial
803036655
Refresh / retry
3600 s / 900 s
Expire
1209600 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns3.uni-konstanz.de (141.37.18.100)803036655
dns3.uni-konstanz.de (2001:7c0:5f0:f504::18:100)803036655
ns3.uni-konstanz.de (134.34.242.3)803036655
ns3.uni-konstanz.de (2001:7c0:2880:2010::31:3)803036655
ns4.uni-konstanz.de (134.34.242.4)803036655
ns4.uni-konstanz.de (2001:7c0:2880:2010::31:4)803036655

Checks

  • ✓ Serial 803036655 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 1h, retry 15m, expire 14d, negative TTL 1h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns3.uni-konstanz.de is one of the listed nameservers.
  • ✓ Contact hostmaster@uni-konstanz.de #25
    The SOA RNAME hostmaster.uni-konstanz.de means hostmaster@uni-konstanz.de.
  • ✓ Counter serial #26
    The serial 803036655 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

17 records at the apex

Found

Read from
141.37.18.100:53
TypeValueTTL
SOAns3.uni-konstanz.de. hostmaster.uni-konstanz.de. 803036655 3600 900 1209600 360086400
NSns4.uni-konstanz.de.86400
NSdns3.uni-konstanz.de.86400
NSns3.uni-konstanz.de.86400
A134.34.247.986400
AAAA2001:7c0:2880:2001::200986400
MX20 adenin2.uni-konstanz.de.86400
MX20 thymin2.uni-konstanz.de.86400
TXT"cisco-ci-domain-verification=6da3fd39006d05bd2e40d4945b5b7e9cde0302042a2b2253cd5986311736e4cc"86400
TXT"MS=ms17599286"86400
TXT"v=spf1 ip4:134.34.240.32/27 ip4:91.198.250.0/24 include:_spf.tivian.com include:_spf.zimpel.de ~all"86400
TXT"MS=ms72256970"86400
TXT"google-site-verification=x7016U-M-j0bftCLHQ9y4r9jaGWldlk3UPU8RWcAam4"86400
TXT"_telesec-domain-validation=2023-11-02_6AdcAFxWOJkgsnTla1pLjN0iUrEvKvxC3Psrt5OTdMHQaDgHpA"86400
TXT"_telesec-domain-validation=341964_2025-10-23_XhRC6QCqLOR3FIVs2cuqYP9otlsuccHUs64Lhs1fWx3yjdeiKQ"86400
TXT"brevo-code:709e7fe481286b7cf280d31ee838a75b"86400
TXT"MS=2FBDB7375211B0E811786C14A5CE6627FC587161"86400

Checks

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