hs-offenburg.de

Checked 21 October 2026, 22:51 UTC · via 8.8.8.8
✗Problems found
21 passed 2 warnings 1 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

dns1.belwue.de, dns1.hs-offenburg.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.hs-offenburg.de, dns3.belwue.de, dns5.belwue.de
NS in the zone
dns1.belwue.de, dns1.hs-offenburg.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.hs-offenburg.de141.79.128.4 2001:7c0:1300:5080::128:4AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE141.79.128.4 2001:7c0:1300:5080::128:4
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.hs-offenburg.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.hs-offenburg.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 4 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): 8 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

fail

7 of 8 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, 8 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns1.hs-offenburg.de 141.79.128.4NOERROR, 11 ms, authoritativenoyes / yesrefused9.16.50
dns1.hs-offenburg.de 2001:7c0:1300:5080::128:4no responsenono / no--
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)
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

  • ✗
    Nameservers not responding
    These addresses did not answer, so resolvers waste time on timeouts: dns1.hs-offenburg.de (2001:7c0:1300:5080::128:4): read udp [2a01:4f8:1c1c:eebf::1]:34659->[2001:7c0:1300:5080::128:4]:53: i/o timeout.
    #14
  • ✓ 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)"; dns1.hs-offenburg.de: "9.16.50"; 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 202608111 · primary dns1.hs-offenburg.de

Found

Primary (MNAME)
dns1.hs-offenburg.de
Contact (RNAME)
hostmaster.hs-offenburg.de
Serial
202608111
Refresh / retry
10800 s / 3600 s
Expire
604800 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
dns1.belwue.de (129.143.2.10)202608111
dns1.belwue.de (2001:7c0::53:10)202608111
dns1.hs-offenburg.de (141.79.128.4)202608111
dns3.belwue.de (129.143.253.133)202608111
dns3.belwue.de (2001:7c0:0:253::133)202608111
dns5.belwue.de (129.143.4.5)202608111
dns5.belwue.de (2001:7c0::53:5)202608111

Checks

  • ✓ Serial 202608111 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 7d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns1.hs-offenburg.de is one of the listed nameservers.
  • ✓ Contact hostmaster@hs-offenburg.de #25
    The SOA RNAME hostmaster.hs-offenburg.de means hostmaster@hs-offenburg.de.
  • ✓ Counter serial #26
    The serial 202608111 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

21 records at the apex

Found

Read from
129.143.2.10:53
TypeValueTTL
SOAdns1.hs-offenburg.de. hostmaster.hs-offenburg.de. 202608111 10800 3600 604800 864003600
NSdns3.belwue.de.400
NSdns5.belwue.de.400
NSdns1.belwue.de.400
NSdns1.hs-offenburg.de.400
A54.36.113.235300
MX5 alt2.aspmx.l.google.com.3600
MX5 alt1.aspmx.l.google.com.3600
MX10 alt4.aspmx.l.google.com.3600
MX10 alt3.aspmx.l.google.com.3600
MX1 aspmx.l.google.com.3600
TXT"HARICA-JQB7UKjhbNtSIwjh5lX"400
TXT"atlassian-sending-domain-verification=1614f801-121f-491d-a16f-3570cdf15fcf"400
TXT"MS=ms86326276"400
TXT"academiccloud-site-verification=GPyWH5J3BgSCRRbGNPcnkC3jK"400
TXT"MS=ms52930853"400
TXT"v=spf1 a ip4:141.79.11.25 ip6:2001:7c0:1300:500b::11:25 include:_spf.google.com ~all"400
TXT"adobe-idp-site-verification=f791f6bd688bb93509040a89f7635df17f9df367306af0f9fb98a6399d3695d4"400
TXT"brevo-code:a65bf3864ff61543490f07c028c8d4ff"400
TXT"MS=ms83318499"400
TXT"atlassian-domain-verification=iEA3dj72n0XOjVgxmLhC3myUOgdX5aXnN8Ji59rBJiJvVh5FIsYHJvWM3SLohr8K"400

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, MX 1h, NS 6m40s. The NS TTL at the parent is 1d and in the zone 6m40s; 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.
  • 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