guug.de

Checked 21 October 2026, 22:41 UTC · via 8.8.8.8
✗Problems found
22 passed 2 warnings 1 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

pass

ns1.linuxtag.net, ns2.dnspartner.de, ns2.guug.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns1.linuxtag.net, ns2.dnspartner.de, ns2.guug.de
NS in the zone
ns1.linuxtag.net, ns2.dnspartner.de, ns2.guug.de
NameserverAddressesNetwork (AS)Glue
ns1.linuxtag.net91.184.37.10 2a01:198:12::aAS34225 SpeedPartner - SpeedPartner GmbH, DE AS34225 SpeedPartner - SpeedPartner GmbH, DE-
ns2.dnspartner.de178.33.39.66 2001:41d0:304:200::c92aAS16276 OVH - OVH SAS, FR AS16276 OVH - OVH SAS, FR178.33.39.66 2001:41d0:304:200::c92a
ns2.guug.de46.4.78.167 2a01:4f8:140:54e4::2AS24940 HETZNER-AS - Hetzner Online GmbH, DE AS24940 HETZNER-AS - Hetzner Online GmbH, DE46.4.78.167 2a01:4f8:140:54e4::2

Checks

  • ✓ 3 nameservers #6
    Delegated to ns1.linuxtag.net, ns2.dnspartner.de, ns2.guug.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: ns2.guug.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 3 IPv6 /48s.
  • ✓ 3 autonomous systems #11
    The nameservers are spread over: AS16276 (OVH - OVH SAS, FR): 2 addresses; AS24940 (HETZNER-AS - Hetzner Online GmbH, DE): 2 addresses; AS34225 (SpeedPartner - SpeedPartner GmbH, DE): 2 addresses.
  • ✓ Nameserver names under 2 TLDs #12
    Nameserver names use the TLDs .de, .net.
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

fail

4 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns1.linuxtag.net 91.184.37.10NOERROR, 8 ms, authoritativenoyes / yesrefused-
ns1.linuxtag.net 2a01:198:12::aNOERROR, 8 ms, authoritativenoyes / yesrefused-
ns2.dnspartner.de 178.33.39.66NOERROR, 17 ms, authoritativenoyes / yesrefusedunknown
ns2.dnspartner.de 2001:41d0:304:200::c92aNOERROR, 18 ms, authoritativenoyes / yesrefusedunknown
ns2.guug.de 46.4.78.167no responsenono / no--
ns2.guug.de 2a01:4f8:140:54e4::2no responsenono / no--

Checks

  • ✗
    Nameservers not responding
    These addresses did not answer, so resolvers waste time on timeouts: ns2.guug.de (46.4.78.167): read udp 46.225.38.91:44961->46.4.78.167:53: i/o timeout; ns2.guug.de (2a01:4f8:140:54e4::2): read udp [2a01:4f8:1c1c:eebf::1]:57442->[2a01:4f8:140:54e4::2]: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.
  • i
    Identifying string disclosed
    These nameservers answer version queries with a string that is not a version number: ns2.dnspartner.de: "unknown".
    #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

warn

serial 2026032401 · primary ns1.linuxtag.net

Found

Primary (MNAME)
ns1.linuxtag.net
Contact (RNAME)
hostmaster.guug.de
Serial
2026032401
Refresh / retry
3600 s / 7200 s
Expire
1209600 s
Negative TTL
600 s

Serial per nameserver

NameserverSerial
ns1.linuxtag.net (91.184.37.10)2026032401
ns1.linuxtag.net (2a01:198:12::a)2026032401
ns2.dnspartner.de (178.33.39.66)2026032401
ns2.dnspartner.de (2001:41d0:304:200::c92a)2026032401

Checks

  • ✓ Serial 2026032401 everywhere #22
    All nameservers serve the same version of the zone.
  • !
    Unusual SOA timers
    retry 2h should be shorter than refresh 1h. Current values: refresh 1h, retry 2h, expire 14d, negative TTL 10m.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.linuxtag.net is one of the listed nameservers.
  • ✓ Contact hostmaster@guug.de #25
    The SOA RNAME hostmaster.guug.de means hostmaster@guug.de.
  • ✓ Date-based serial #26
    The serial 2026032401 follows the YYYYMMDDnn convention (2026-03-24).

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

9 records at the apex

Found

Read from
91.184.37.10:53
TypeValueTTL
SOAns1.linuxtag.net. hostmaster.guug.de. 2026032401 3600 7200 1209600 600600
NSns2.dnspartner.de.600
NSns1.linuxtag.net.600
NSns2.guug.de.600
A91.184.37.45600
AAAA2a01:198:12::2d600
MX10 mx.guug.de.600
TXT"_globalsign-domain-verification=b0kbg9XYe9XfJ7DFcWx7_6cJVGfVWvs9BeSQ0F8OyI"600
TXT"v=spf1 mx mx:linuxtag.org ?all"600

Checks

  • ✓ TTLs within range #32
    TTLs: A 10m, AAAA 10m, MX 10m, NS 10m. The NS TTL at the parent is 1d and in the zone 10m; 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