uni-siegen.de

Checked 22 October 2026, 00:50 UTC · via 8.8.8.8
!Passed with warnings
22 passed 1 warning 0 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

info

adebar.uni-siegen.de, dns-1.dfn.de, si-nic.hrz.uni-siegen.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
adebar.uni-siegen.de, dns-1.dfn.de, si-nic.hrz.uni-siegen.de
NS in the zone
adebar.uni-siegen.de, dns-1.dfn.de, si-nic.hrz.uni-siegen.de
NameserverAddressesNetwork (AS)Glue
adebar.uni-siegen.de141.99.8.100 2a04:dfc0:90:17::100AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE141.99.8.100 2a04:dfc0:90:17::100
dns-1.dfn.de193.174.75.50 2001:638:d:b101::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
si-nic.hrz.uni-siegen.de141.99.2.2 2a04:dfc0:dc:2::2AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE141.99.2.2 2a04:dfc0:dc:2::2

Checks

  • ✓ 3 nameservers #6
    Delegated to adebar.uni-siegen.de, dns-1.dfn.de, si-nic.hrz.uni-siegen.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: adebar.uni-siegen.de, si-nic.hrz.uni-siegen.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.
  • 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): 6 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

info

6 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
adebar.uni-siegen.de 141.99.8.100NOERROR, 13 ms, authoritativenoyes / yesrefused-
adebar.uni-siegen.de 2a04:dfc0:90:17::100NOERROR, 13 ms, authoritativenoyes / yesrefused-
dns-1.dfn.de 193.174.75.50NOERROR, 12 ms, authoritativenoyes / yesrefused0
dns-1.dfn.de 2001:638:d:b101::1NOERROR, 14 ms, authoritativenoyes / yesrefused0
si-nic.hrz.uni-siegen.de 141.99.2.2NOERROR, 13 ms, authoritativenoyes / yesrefused-
si-nic.hrz.uni-siegen.de 2a04:dfc0:dc:2::2NOERROR, 13 ms, authoritativenoyes / yesrefused-

Checks

  • ✓ All respond #14
    All 6 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: dns-1.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 2010290862 · primary si-nic.hrz.uni-siegen.de

Found

Primary (MNAME)
si-nic.hrz.uni-siegen.de
Contact (RNAME)
dnsmaster.zimt.uni-siegen.de
Serial
2010290862
Refresh / retry
10800 s / 3600 s
Expire
2592000 s
Negative TTL
900 s

Serial per nameserver

NameserverSerial
adebar.uni-siegen.de (141.99.8.100)2010290862
adebar.uni-siegen.de (2a04:dfc0:90:17::100)2010290862
dns-1.dfn.de (193.174.75.50)2010290862
dns-1.dfn.de (2001:638:d:b101::1)2010290862
si-nic.hrz.uni-siegen.de (141.99.2.2)2010290862
si-nic.hrz.uni-siegen.de (2a04:dfc0:dc:2::2)2010290862

Checks

  • ✓ Serial 2010290862 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 30d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver si-nic.hrz.uni-siegen.de is one of the listed nameservers.
  • ✓ Contact dnsmaster@zimt.uni-siegen.de #25
    The SOA RNAME dnsmaster.zimt.uni-siegen.de means dnsmaster@zimt.uni-siegen.de.
  • ✓ Timestamp serial #26
    The serial 2010290862 is a Unix timestamp (2033-09-14 06:07 UTC).

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

32 records at the apex

Found

Read from
141.99.8.100:53
TypeValueTTL
SOAsi-nic.hrz.uni-siegen.de. dnsmaster.zimt.uni-siegen.de. 2010290862 10800 3600 2592000 90028800
NSadebar.uni-siegen.de.28800
NSdns-1.dfn.de.28800
NSsi-nic.hrz.uni-siegen.de.28800
A141.99.11.5600
A141.99.11.16600
A141.99.13.18600
A141.99.13.19600
MX10 smtp-public.uni-siegen.de.28800
TXT"v=spf1 include:spf.uni-siegen.de ~all"3600
TXT"7UUFdMt6mDbwtvRI6E2yT07c0dz9KXD5Q/cviM5GaXqBO+N2YuMV8Hy/5jGXihUoYQU1NeP4z6/T7Qz9hW7/dg=="3600
TXT"ZOOM_verify_Bl2rwgK_Sa2FZNYkOvREug"3600
TXT"apple-domain-verification=nWX5aOzLeIBfwTQM"3600
TXT"google-site-verification=9a8VzoE21GSlxSONW9W-Id1V1w4dNOcezn18i-6_8vY"3600
TXT"cisco-ci-domain-verification=5019fb982f02ea7fe1fb28d150d36f5eedc30603575ca706ee86a6ef58e502e7"3600
TXT"_telesec-domain-validation=316770_2023-03-01_7Ni0vPC4fkxbRRSYLR0YxJU98Q0iGyOKxfsZvZsAli6Onhs1QE"3600
TXT"successfactors-site-verification=OTFmNTBmM2MwOTU5YjIwMWEyNzE2OTljNzRlOWQwMTlmNjc5NGIyMGNmYjA1ODZhYmM4ODUwMzcyZDRmZWVmNA=="3600
TXT"HARICA-hZTAqiuh2W53jRtyWxa"3600
TXT"_telesec-domain-validation=331542_2025-01-07_SMeOQGr78uWXmms3GmOF4rSRfsIS2jp5RxWQ99ERbYrgyxDSIP"3600
TXT"HARICA-lWeykBh0O3AuoSQYS0R"3600
TXT"google-gws-recovery-domain-verification=70895856"3600
TXT"HARICA-41JpeJHJ9pIH9pvG7gc"3600
TXT"HARICA-ObNiy0I93pm1FYiRbVW"3600
TXT"riot-domain-verification=c76914233ab9da9f067a829e678429be0b353c29b13f1042f248d260d630"3600
TXT"HARICA-XbiRuKgUcNheq2vLf8h"3600
TXT"HARICA-GqFsIkun82vTTPVBTfi"3600
TXT"HARICA-3ZdlM2ZKbCZQI10ILla"3600
TXT"HARICA-z5VXEqILIW9RFZpNF49"3600
TXT"HARICA-34WAqbI110NSYkrbmz3"3600
TXT"google-site-verification=sWPrdfG79HWTe9WzUt3S6nkJOSQZvYXEfHl3NhmIrdw"3600
TXT"adobe-idp-site-verification=ff41cdc79a9d59dcac130462fb19847a293bdccca2d91afc01cebead73921087"3600
TXT"MS=E9F312600E63807E220CCB0FF86DD36D74EF2276"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 10m, MX 8h, NS 8h. The NS TTL at the parent is 1d and in the zone 8h; 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