blb-karlsruhe.de

Checked 21 October 2026, 21:48 UTC · via 8.8.8.8
!Passed with warnings
24 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

dns1.belwue.de, dns1.blb-karlsruhe.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, dns1.blb-karlsruhe.de, dns3.belwue.de, dns5.belwue.de
NS in the zone
dns1.belwue.de, dns1.blb-karlsruhe.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
dns1.blb-karlsruhe.de193.197.86.1AS553 BELWUE - Universitaet Stuttgart, DE193.197.86.1
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

  • ✓ 4 nameservers #6
    Delegated to dns1.belwue.de, dns1.blb-karlsruhe.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.
  • ✓ Glue present and correct #8
    Glue is published for the nameservers inside the zone: dns1.blb-karlsruhe.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): 7 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: dns1.blb-karlsruhe.de.
    #13

Nameservers

warn

7 of 7 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)
dns1.blb-karlsruhe.de 193.197.86.1NOERROR, 11 ms, authoritativenoyes / yesrefusedVersion - Badische Landesbibliothek
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, 8 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, 8 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)

Checks

  • ✓ All respond #14
    All 7 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

pass

serial 2026100147 · primary dns1.blb-karlsruhe.de

Found

Primary (MNAME)
dns1.blb-karlsruhe.de
Contact (RNAME)
administrator.blb-karlsruhe.de
Serial
2026100147
Refresh / retry
3600 s / 600 s
Expire
1209600 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns1.belwue.de (129.143.2.10)2026100147
dns1.belwue.de (2001:7c0::53:10)2026100147
dns1.blb-karlsruhe.de (193.197.86.1)2026100147
dns3.belwue.de (129.143.253.133)2026100147
dns3.belwue.de (2001:7c0:0:253::133)2026100147
dns5.belwue.de (129.143.4.5)2026100147
dns5.belwue.de (2001:7c0::53:5)2026100147

Checks

  • ✓ Serial 2026100147 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 1h, retry 10m, expire 14d, negative TTL 1h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns1.blb-karlsruhe.de is one of the listed nameservers.
  • ✓ Contact administrator@blb-karlsruhe.de #25
    The SOA RNAME administrator.blb-karlsruhe.de means administrator@blb-karlsruhe.de.
  • ✓ Date-based serial #26
    The serial 2026100147 follows the YYYYMMDDnn convention (2026-10-01).

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver
yes
Denial of existence
NSEC
Signatures valid until
28 October 2026

DS at the parent

Key tagAlgorithmDigestMatches a key
26924ECDSAP256SHA256 (13)SHA256 F7CBC5B5684DAD5C…yes

DNSKEY in the zone

Key tagRoleAlgorithm
26924KSK (257)ECDSAP256SHA256 (13)

Checks

  • ✓ Signed and validated #27
    The zone is signed, the parent publishes a DS record, and the resolver validates the answers.
  • ✓ DS matches a key #28
    The DS record at the parent matches a key in the zone: key tag 26924 (SHA256).
  • ✓ Modern algorithms #29
    Key algorithms: ECDSAP256SHA256 (13).
  • !
    Signatures expire soon
    The earliest signature expires at 2026-10-28 20:32 UTC (in 167h0m0s). Check that automatic re-signing works.
    #30
  • i
    NSEC
    The zone uses NSEC, so its full contents can be listed by walking the NSEC chain. That is fine unless the names are sensitive.
    #31

Records

pass

20 records at the apex

Found

Read from
129.143.2.10:53
TypeValueTTL
SOAdns1.blb-karlsruhe.de. administrator.blb-karlsruhe.de. 2026100147 3600 600 1209600 360010800
NSdns3.belwue.de.10800
NSdns1.belwue.de.10800
NSdns1.blb-karlsruhe.de.10800
NSdns5.belwue.de.10800
A193.197.86.22110800
MX10 mx2.belwue.de.10800
MX10 mx3.belwue.de.10800
MX10 mx4.belwue.de.10800
MX10 mx1.belwue.de.10800
TXT"HARICA-prGkaClmMJGRab0DoV5"10800
TXT"MS=6209B949AFAC4B6A0317619D1CF451312690AD23"10800
TXT"v=spf1 a:mail.blb-karlsruhe.de a:mailgw.blb-karlsruhe.de ip4:193.197.86.3 ip4:193.197.86.30 -all"10800
TXT"google-site-verification=N7oRe83oloM7DpcK3kOy41t4C8LX4E1DvMx9Iy2Iw34"10800
TXT"apple-domain-verification=6VIoI5bqWQ8w6WlS"10800
CAA0 issue "harica.gr"10800
CAA0 iodef "mailto:hostmaster@blb-karlsruhe.de"10800
CAA0 issue "pki.dfn.de"10800
CAA0 issuewild "harica.gr"10800
CAA0 issuewild "pki.dfn.de"10800

Checks

  • ✓ TTLs within range #32
    TTLs: A 3h, MX 3h, NS 3h. The NS TTL at the parent is 1d and in the zone 3h; 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.
  • ✓ CAA restricts issuance #35
    Certificates may be issued by: harica.gr, pki.dfn.de.