bsz-bw.de

Checked 21 October 2026, 21:54 UTC · via 8.8.8.8
!Passed with warnings
21 passed 2 warnings 0 failed 6 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

dns1.belwue.de, dns3.belwue.de, dns5.belwue.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns1.belwue.de, dns3.belwue.de, dns5.belwue.de
NS in the zone
dns1.belwue.de, dns3.belwue.de, dns5.belwue.de
NameserverAddressesNetwork (AS)Glue
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
dns5.belwue.de129.143.4.5 2001:7c0::53:5AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE129.143.4.5 2001:7c0::53:5

Checks

  • ✓ 3 nameservers #6
    Delegated to dns1.belwue.de, dns3.belwue.de, dns5.belwue.de.
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • ✓ No glue needed #8
    All nameservers are outside the zone, so no glue records are needed.
  • ✓ 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
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

warn

6 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
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, 8 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns5.belwue.de 129.143.4.5NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns5.belwue.de 2001:7c0::53:5NOERROR, 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)"; dns5.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

info

serial 2026102100 · primary bcn-dns-prim.kim.uni-konstanz.de

Found

Primary (MNAME)
bcn-dns-prim.kim.uni-konstanz.de
Contact (RNAME)
hostmaster.bsz-bw.de
Serial
2026102100
Refresh / retry
14400 s / 3600 s
Expire
2419200 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns1.belwue.de (129.143.2.10)2026102100
dns1.belwue.de (2001:7c0::53:10)2026102100
dns3.belwue.de (129.143.253.133)2026102100
dns3.belwue.de (2001:7c0:0:253::133)2026102100
dns5.belwue.de (129.143.4.5)2026102100
dns5.belwue.de (2001:7c0::53:5)2026102100

Checks

  • ✓ Serial 2026102100 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 4h, retry 1h, expire 28d, negative TTL 1h.
  • i
    Hidden master
    The primary nameserver bcn-dns-prim.kim.uni-konstanz.de is not listed as a nameserver: a hidden master that only feeds the public secondaries. That is a common setup; make sure it is not reachable for zone transfers from outside.
    #24
  • ✓ Contact hostmaster@bsz-bw.de #25
    The SOA RNAME hostmaster.bsz-bw.de means hostmaster@bsz-bw.de.
  • ✓ Date-based serial #26
    The serial 2026102100 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

14 records at the apex

Found

Read from
129.143.2.10:53
TypeValueTTL
SOAbcn-dns-prim.kim.uni-konstanz.de. hostmaster.bsz-bw.de. 2026102100 14400 3600 2419200 360014400
NSdns3.belwue.de.86400
NSdns5.belwue.de.86400
NSdns1.belwue.de.86400
A91.107.129.13614400
MX10 mx1.belwue.de.14400
MX10 mx4.belwue.de.14400
MX10 mx2.belwue.de.14400
MX10 mx3.belwue.de.14400
TXT"logmein-verification-code=dddec8b9-d421-44d3-9dc0-975674b77081"14400
TXT"Bibliotheksservice-Zentrum Baden-Wuerttemberg, Robert-Gerwig-Str. 4, Konstanz"14400
TXT"v=spf1 ip4:193.197.29.20 ip4:193.197.29.29 include:_spf.belwue.de -all"14400
CAA0 iodef "mailto:certadmin@bsz-bw.de"14400
CAA0 issue "harica.gr"14400

Checks

  • ✓ TTLs within range #32
    TTLs: A 4h, MX 4h, 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: harica.gr.