hgb-leipzig.de

Checked 21 October 2026, 22:50 UTC · via 8.8.8.8
!Passed with warnings
22 passed 2 warnings 0 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

dns-3.dfn.de, hgb1.hgb-leipzig.de, mail.hgb-leipzig.de, news.uni-leipzig.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-3.dfn.de, hgb1.hgb-leipzig.de, mail.hgb-leipzig.de, news.uni-leipzig.de
NS in the zone
dns-3.dfn.de, hgb1.hgb-leipzig.de, mail.hgb-leipzig.de, news.uni-leipzig.de
NameserverAddressesNetwork (AS)Glue
dns-3.dfn.de193.174.75.58 2001:638:d:b103::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
hgb1.hgb-leipzig.de194.94.211.220AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE194.94.211.220
mail.hgb-leipzig.de194.94.211.50AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE194.94.211.50
news.uni-leipzig.de139.18.25.3AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE139.18.25.3

Checks

  • ✓ 4 nameservers #6
    Delegated to dns-3.dfn.de, hgb1.hgb-leipzig.de, mail.hgb-leipzig.de, news.uni-leipzig.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: hgb1.hgb-leipzig.de, mail.hgb-leipzig.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 1 IPv6 /48.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS680 (DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE): 5 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: hgb1.hgb-leipzig.de, mail.hgb-leipzig.de, news.uni-leipzig.de.
    #13

Nameservers

warn

5 of 5 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns-3.dfn.de 193.174.75.58NOERROR, 10 ms, authoritativenoyes / yesrefused0
dns-3.dfn.de 2001:638:d:b103::1NOERROR, 10 ms, authoritativenoyes / yesrefused0
hgb1.hgb-leipzig.de 194.94.211.220NOERROR, 14 ms, authoritativenoyes / yesrefused-
mail.hgb-leipzig.de 194.94.211.50NOERROR, 11 ms, authoritativenoyes / yesrefused9.18.41
news.uni-leipzig.de 139.18.25.3NOERROR, 15 ms, authoritativenoyes / yesrefused:-) ???

Checks

  • ✓ All respond #14
    All 5 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: mail.hgb-leipzig.de: "9.18.41". 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 2026100501 · primary hgb1.hgb-leipzig.de

Found

Primary (MNAME)
hgb1.hgb-leipzig.de
Contact (RNAME)
uklaus.hgb-leipzig.de
Serial
2026100501
Refresh / retry
21600 s / 3000 s
Expire
3600000 s
Negative TTL
7200 s

Serial per nameserver

NameserverSerial
dns-3.dfn.de (193.174.75.58)2026100501
dns-3.dfn.de (2001:638:d:b103::1)2026100501
hgb1.hgb-leipzig.de (194.94.211.220)2026100501
mail.hgb-leipzig.de (194.94.211.50)2026100501
news.uni-leipzig.de (139.18.25.3)2026100501

Checks

  • ✓ Serial 2026100501 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 6h, retry 50m, expire 1000h, negative TTL 2h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver hgb1.hgb-leipzig.de is one of the listed nameservers.
  • ✓ Contact uklaus@hgb-leipzig.de #25
    The SOA RNAME uklaus.hgb-leipzig.de means uklaus@hgb-leipzig.de.
  • ✓ Date-based serial #26
    The serial 2026100501 follows the YYYYMMDDnn convention (2026-10-05).

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

23 records at the apex

Found

Read from
193.174.75.58:53
TypeValueTTL
SOAhgb1.hgb-leipzig.de. uklaus.hgb-leipzig.de. 2026100501 21600 3000 3600000 720021600
NSnews.uni-leipzig.de.21600
NShgb1.hgb-leipzig.de.21600
NSmail.hgb-leipzig.de.21600
NSdns-3.dfn.de.21600
MX25 kunst4.hgb-leipzig.de.21600
MX10 mail.hgb-leipzig.de.21600
MX30 nol.hgb-leipzig.de.21600
MX15 kunst2.hgb-leipzig.de.21600
MX20 hgb1.hgb-leipzig.de.21600
TXT"google-site-verification=LwB2pJGFzrdM8ipwFJzhm3yfMDp1nZY2CWM-7J5YyJE"21600
TXT"cisco-ci-domain-verification=6a8139d0b224ec0dd4684a5b408ae2e90f8edbd7d02303ea392c0909cf0a700f"21600
TXT"v=spf1 mx +ip4:194.94.211.20 +ip4:194.94.211.25 +ip4:194.94.211.153 +ip4:194.94.211.218 +ip4:194.94.211.246 -all"21600
TXT"apple-domain-verification=qU4SJFqd7YNJcGMS"21600
TXT"brevo-code:4c7a63b05454067d6516926916155499"21600
TXT"adobe-idp-site-verification=d20559cf7193b80be327c51f69ba0b4b662cce4922f076931d8a1d9e22497164"21600
TXT"ZOOM_verify_oynzWZHENGBf6dn8jmER4o"21600
TXT"_telesec-domain-validation=343168_2025-11-17_uN27hAT7yJkfJHQ0bfK0MGLbdAiMNky532PhqOPxQ1p8Bs3JtS"21600
CAA0 issue "telesec.de"21600
CAA0 issue "pki.dfn.de"21600
CAA0 issue "harica.gr"21600
CAA0 iodef "mailto:ca@hgb-leipzig.de"21600
CAA0 issue "sectigo.com"21600

Checks

  • ✓ TTLs within range #32
    TTLs: MX 6h, NS 6h. The NS TTL at the parent is 1d and in the zone 6h; 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: telesec.de, pki.dfn.de, harica.gr, sectigo.com.