fh-swf.de

Checked 21 October 2026, 22:20 UTC · via 8.8.8.8
✗Problems found
20 passed 2 warnings 1 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

fail

deneb.dfn.de, dnsha.fh-swf.de, dnsis.fh-swf.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
deneb.dfn.de, dnsha.fh-swf.de, dnsis.fh-swf.de
NS in the zone
ddi-manager.its.fh-swf.de, ddi-member.its.fh-swf.de, deneb.dfn.de
NameserverAddressesNetwork (AS)Glue
ddi-manager.its.fh-swf.de (zone only)193.174.68.5 193.174.68.226AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
ddi-member.its.fh-swf.de (zone only)193.174.68.226AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
deneb.dfn.de192.76.176.9 2001:638:800:1::9AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
dnsha.fh-swf.de (parent only)(does not resolve)193.174.68.226
dnsis.fh-swf.de (parent only)(does not resolve)193.174.68.5

Checks

  • ✓ 3 nameservers #6
    Delegated to deneb.dfn.de, dnsha.fh-swf.de, dnsis.fh-swf.de.
  • !
    NS sets differ
    The nameservers at the parent and in the zone should be the same. Only at the parent: dnsha.fh-swf.de, dnsis.fh-swf.de; only in the zone: ddi-manager.its.fh-swf.de, ddi-member.its.fh-swf.de. ddi-manager.its.fh-swf.de, ddi-member.its.fh-swf.de, deneb.dfn.de report NS ddi-manager.its.fh-swf.de ddi-member.its.fh-swf.de deneb.dfn.de.
    #7
  • ✓ Glue present and correct #8
    Glue is published for the nameservers inside the zone: dnsha.fh-swf.de, dnsis.fh-swf.de.
  • ✗
    Nameserver names don't resolve
    These nameservers have no A or AAAA record, so they can't be reached (lame delegation): dnsha.fh-swf.de, dnsis.fh-swf.de.
    #9
  • ✓ Nameservers in different networks #10
    The nameservers are spread over 2 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: ddi-manager.its.fh-swf.de, ddi-member.its.fh-swf.de.
    #13

Nameservers

info

5 of 5 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ddi-manager.its.fh-swf.de 193.174.68.5NOERROR, 13 ms, authoritativenoyes / yesrefused-
ddi-manager.its.fh-swf.de 193.174.68.226NOERROR, 15 ms, authoritativenoyes / yesrefused-
ddi-member.its.fh-swf.de 193.174.68.226NOERROR, 15 ms, authoritativenoyes / yesrefused-
deneb.dfn.de 192.76.176.9NOERROR, 14 ms, authoritativenoyes / yesrefused0
deneb.dfn.de 2001:638:800:1::9NOERROR, 14 ms, authoritativenoyes / yesrefused0

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.
  • i
    Identifying string disclosed
    These nameservers answer version queries with a string that is not a version number: deneb.dfn.de: "0".
    #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 2025061297 · primary ddi-manager.its.fh-swf.de

Found

Primary (MNAME)
ddi-manager.its.fh-swf.de
Contact (RNAME)
noc.fh-swf.de
Serial
2025061297
Refresh / retry
28800 s / 7200 s
Expire
2592000 s
Negative TTL
1800 s

Serial per nameserver

NameserverSerial
ddi-manager.its.fh-swf.de (193.174.68.5)2025061297
ddi-manager.its.fh-swf.de (193.174.68.226)2025061297
ddi-member.its.fh-swf.de (193.174.68.226)2025061297
deneb.dfn.de (192.76.176.9)2025061297
deneb.dfn.de (2001:638:800:1::9)2025061297

Checks

  • ✓ Serial 2025061297 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 8h, retry 2h, expire 30d, negative TTL 30m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ddi-manager.its.fh-swf.de is one of the listed nameservers.
  • ✓ Contact noc@fh-swf.de #25
    The SOA RNAME noc.fh-swf.de means noc@fh-swf.de.
  • ✓ Date-based serial #26
    The serial 2025061297 follows the YYYYMMDDnn convention (2025-06-12).

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

20 records at the apex

Found

Read from
193.174.68.5:53
TypeValueTTL
SOAddi-manager.its.fh-swf.de. noc.fh-swf.de. 2025061297 28800 7200 2592000 18001800
NSddi-member.its.fh-swf.de.1800
NSdeneb.dfn.de.1800
NSddi-manager.its.fh-swf.de.1800
A193.174.68.101800
MX100 itsmx-02.fh-swf.de.1800
MX100 itsmx-01.fh-swf.de.1800
TXT"v=spf1 redirect=_spf.fh-swf.de"1800
TXT"_telesec-domain-validation=342233_2024-11-12_cN7kyqZu1wmVlg0DY8xPwu2zQeIOaJQt0KJoI1ZnbFwREcFIj8"1800
TXT"google-site-verification=E5tZXhIzkA0pkG8k1IF-pVXCRVSshDGR_xjdB21gQAs"1800
TXT"google-site-verification=8b7qSW1QjRV5shO1BKeKGXvpfe0bF8qVVeGQBCjWXzM"1800
TXT"MS=2E71BC72D4C8800CDB290A8E21384D01C122A31D"1800
TXT"adobe-idp-site-verification=90db0f0ec9783ea98277a2ea73946f404c5397d8a01579aa5ae9fddd944e6fce"1800
TXT"ZOOM_verify_D4rWiChESEy4mBgMO_AGOg"1800
TXT"spycloud-domain-verification=ab669a6e-368f-4b52-8236-bc2d59ce827d"1800
CAA0 issue "pki.dfn.de"1800
CAA0 issue "harica.gr"1800
CAA0 issue "letsencrypt.org"1800
CAA0 issue "telesec.de"1800
CAA0 iodef "mailto:noc@fh-swf.de"1800

Checks

  • ✓ TTLs within range #32
    TTLs: A 30m, MX 30m, NS 30m. The NS TTL at the parent is 1d and in the zone 30m; 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: pki.dfn.de, harica.gr, letsencrypt.org, telesec.de.