dhbw.de

Checked 21 October 2026, 22:14 UTC · via 8.8.8.8
!Passed with warnings
23 passed 2 warnings 0 failed 4 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

dns02.dhbw.de, dns1.belwue.de, dns3.belwue.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns02.dhbw.de, dns1.belwue.de, dns3.belwue.de
NS in the zone
dns02.dhbw.de, dns1.belwue.de, dns3.belwue.de
NameserverAddressesNetwork (AS)Glue
dns02.dhbw.de141.31.235.12 2001:7c0:1bc0:1::12AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE141.31.235.12 2001:7c0:1bc0:1::12
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
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

  • ✓ 3 nameservers #6
    Delegated to dns02.dhbw.de, dns1.belwue.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: dns02.dhbw.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 (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
dns02.dhbw.de 141.31.235.12NOERROR, 7 ms, authoritativenoyes / yesrefused-
dns02.dhbw.de 2001:7c0:1bc0:1::12NOERROR, 7 ms, authoritativenoyes / yesrefused-
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)
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: dns1.belwue.de: "PowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)"; 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 2026101502 · primary dns02.dhbw.de

Found

Primary (MNAME)
dns02.dhbw.de
Contact (RNAME)
hostmaster.dhbw.de
Serial
2026101502
Refresh / retry
3600 s / 900 s
Expire
1209600 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns02.dhbw.de (141.31.235.12)2026101502
dns02.dhbw.de (2001:7c0:1bc0:1::12)2026101502
dns1.belwue.de (129.143.2.10)2026101502
dns1.belwue.de (2001:7c0::53:10)2026101502
dns3.belwue.de (129.143.253.133)2026101502
dns3.belwue.de (2001:7c0:0:253::133)2026101502

Checks

  • ✓ Serial 2026101502 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 dns02.dhbw.de is one of the listed nameservers.
  • ✓ Contact hostmaster@dhbw.de #25
    The SOA RNAME hostmaster.dhbw.de means hostmaster@dhbw.de.
  • ✓ Date-based serial #26
    The serial 2026101502 follows the YYYYMMDDnn convention (2026-10-15).

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

20 records at the apex

Found

Read from
141.31.235.12:53
TypeValueTTL
SOAdns02.dhbw.de. hostmaster.dhbw.de. 2026101502 3600 900 1209600 360086400
NSdns1.belwue.de.86400
NSdns3.belwue.de.86400
NSdns02.dhbw.de.86400
A141.31.235.5086400
MX30 mx03.hornetsecurity.com.600
MX40 mx04.hornetsecurity.com.600
MX20 mx02.hornetsecurity.com.600
MX10 mx01.hornetsecurity.com.600
TXT"v=spf1 ip4:141.31.235.1 ip4:141.31.235.101 ip4:141.72.3.5 ip4:141.72.3.10 ip4:141.72.3.12 ip6:2001:7c0:1b20::10 ip6:2001:7c0:1b20::12 include:_spf.belwue.de include:spf.dynect.net ip4:212.227.17.10 ip4:212.227.17.13 ip4:212.227.17.24 ip4:212.227.126.130 i" "p4:212.227.126.131 ip4:212.227.126.133 ip4:212.227.126.134 ip4:212.227.126.135 ip4:212.227.126.187 ip4:217.72.192.73 ip4:217.72.192.74 ip4:217.72.192.75 include:spf.hornetsecurity.com include:_spf.ubicast.tv include:mailgun.org -all"600
TXT"google-site-verification=PEVpBE-B7h07uY8wlx7XAhUzln0zmJWt67mBM04AZvc"600
TXT"MS=6FE0A6DFAEFE33B30F417681EC741A6710FD2A18"600
TXT"HARICA-uyZ5Pvm90a76TSMq3a2"600
CAA0 issue "usertrust.com"60
CAA0 iodef "mailto:abuse@dhbw.de"60
CAA0 issue "sectigo.com"60
CAA0 issue "pki.dfn.de"60
CAA0 issue "harica.gr"60
CAA0 issue "letsencrypt.org"60
CAA0 issue "trust-provider.com"60

Checks

  • ✓ TTLs within range #32
    TTLs: A 1d, MX 10m, 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.
  • ✓ CAA restricts issuance #35
    Certificates may be issued by: usertrust.com, sectigo.com, pki.dfn.de, harica.gr, letsencrypt.org, trust-provider.com.