uni-heidelberg.de

Checked 22 October 2026, 00:50 UTC · via 8.8.8.8
!Passed with warnings
20 passed 2 warnings 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.uni-heidelberg.de, dns1.belwue.de, dns2.uni-heidelberg.de, dns3.belwue.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns.uni-heidelberg.de, dns1.belwue.de, dns2.uni-heidelberg.de, dns3.belwue.de
NS in the zone
dns.uni-heidelberg.de, dns1.belwue.de, dns2.uni-heidelberg.de, dns3.belwue.de
NameserverAddressesNetwork (AS)Glue
dns.uni-heidelberg.de129.206.100.126AS553 BELWUE - Universitaet Stuttgart, DE129.206.100.126
dns1.belwue.de129.143.2.10 2001:7c0::53:10AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE129.143.2.10 2001:7c0::53:10
dns2.uni-heidelberg.de129.206.210.127AS553 BELWUE - Universitaet Stuttgart, DE129.206.210.127
dns3.belwue.de129.143.253.133 2001:7c0:0:253::133AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE129.143.253.133 2001:7c0:0:253::133

Checks

  • ✓ 4 nameservers #6
    Delegated to dns.uni-heidelberg.de, dns1.belwue.de, dns2.uni-heidelberg.de, dns3.belwue.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: dns.uni-heidelberg.de, dns2.uni-heidelberg.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 2001:7c0::/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 (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
  • i
    Partly IPv6
    These nameservers have no IPv6 address: dns.uni-heidelberg.de, dns2.uni-heidelberg.de.
    #13

Nameservers

warn

6 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns.uni-heidelberg.de 129.206.100.126NOERROR, 8 ms, authoritativenoyes / yesrefused9.11.36-RedHat-9.11.36-16.el8_10.16
dns1.belwue.de 129.143.2.10NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns1.belwue.de 2001:7c0::53:10NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns2.uni-heidelberg.de 129.206.210.127NOERROR, 8 ms, authoritativenoyes / yesrefused9.11.36-RedHat-9.11.36-16.el8_10.16
dns3.belwue.de 129.143.253.133NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns3.belwue.de 2001:7c0:0:253::133NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)

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: dns.uni-heidelberg.de: "9.11.36-RedHat-9.11.36-16.el8_10.16"; dns1.belwue.de: "PowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)"; dns2.uni-heidelberg.de: "9.11.36-RedHat-9.11.36-16.el8_10.16"; dns3.belwue.de: "PowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)". 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 202610210 · primary dns.uni-heidelberg.de

Found

Primary (MNAME)
dns.uni-heidelberg.de
Contact (RNAME)
net-bugs.urz.uni-heidelberg.de
Serial
202610210
Refresh / retry
21600 s / 1800 s
Expire
2419200 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns.uni-heidelberg.de (129.206.100.126)202610210
dns1.belwue.de (129.143.2.10)202610210
dns1.belwue.de (2001:7c0::53:10)202610210
dns2.uni-heidelberg.de (129.206.210.127)202610210
dns3.belwue.de (129.143.253.133)202610210
dns3.belwue.de (2001:7c0:0:253::133)202610210

Checks

  • ✓ Serial 202610210 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 6h, retry 30m, expire 28d, negative TTL 1h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns.uni-heidelberg.de is one of the listed nameservers.
  • ✓ Contact net-bugs@urz.uni-heidelberg.de #25
    The SOA RNAME net-bugs.urz.uni-heidelberg.de means net-bugs@urz.uni-heidelberg.de.
  • ✓ Counter serial #26
    The serial 202610210 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
129.206.100.126:53
TypeValueTTL
SOAdns.uni-heidelberg.de. net-bugs.urz.uni-heidelberg.de. 202610210 21600 1800 2419200 360086400
NSdns3.belwue.de.86400
NSdns.uni-heidelberg.de.86400
NSdns1.belwue.de.86400
NSdns2.uni-heidelberg.de.86400
A129.206.13.7186400
MX10 relay.uni-heidelberg.de.86400
MX10 relay3.uni-heidelberg.de.86400
MX10 relay2.uni-heidelberg.de.86400
TXT"cloudflare-verify.uni-heidelberg.de 392311672-383734000"86400
TXT"1 baa827de-94e8-11d1-9294-0006292e8152 Readonly /.../uni-heidelberg.de/dcesrv2_ch 13228860-ad1b-11d1-9b86-0006292e7ae1 dcesrv2.urz.uni-heidelberg.de"86400
TXT"v=spf1 ip4:129.206.100.212 ip4:129.206.119.212 ip4:129.206.100.213 ip4:129.206.119.213 ip4:129.206.100.214 include:spf.protection.outlook.com mx -all"86400
TXT"google-site-verification=HZuDm00bKKT2fU_i2mLun2aw8IUNa64kg9ilP3b8-AQ"86400
TXT"HARICA-DC3snpUvLUznExHxhK6"86400
TXT"1 baa827de-94e8-11d1-9294-0006292e8152 Master /.../uni-heidelberg.de/dcesrv1_ch ba2928f8-94e8-11d1-9294-0006292e8152 dcesrv1.urz.uni-heidelberg.de"86400
TXT"apple-domain-verification=rTpijAWdQfNd3V8I"86400
TXT"cisco-ci-domain-verification=30f96646ddb8814399410d5700143249881b4eb5948ddcc31e894591877b7f84"86400

Checks

  • ✓ TTLs within range #32
    TTLs: A 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