aip.de

Checked 21 October 2026, 21:28 UTC · via 8.8.8.8
✗Problems found
19 passed 1 warning 1 failed 8 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-2.dfn.de, dns-3.dfn.de, pns.aip.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-2.dfn.de, dns-3.dfn.de, pns.aip.de
NS in the zone
dns-2.dfn.de, dns-3.dfn.de, pns.aip.de
NameserverAddressesNetwork (AS)Glue
dns-2.dfn.de193.174.75.54 2001:638:d:b102::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
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-
pns.aip.de141.33.207.16AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE141.33.207.16

Checks

  • ✓ 3 nameservers #6
    Delegated to dns-2.dfn.de, dns-3.dfn.de, pns.aip.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: pns.aip.de.
  • ✓ All names resolve #9
    Every nameserver name has an address and is not an alias.
  • i
    One address family in one network
    all IPv6 addresses are in 2001:638:d::/48, while the other address family is spread over several networks.
    #10
  • 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: pns.aip.de.
    #13

Nameservers

fail

5 of 5 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns-2.dfn.de 193.174.75.54NOERROR, 7 ms, authoritativenoyes / yesrefused0
dns-2.dfn.de 2001:638:d:b102::1NOERROR, 7 ms, authoritativenoyes / yesrefused0
dns-3.dfn.de 193.174.75.58NOERROR, 10 ms, authoritativenoyes / yesrefused0
dns-3.dfn.de 2001:638:d:b103::1NOERROR, 11 ms, authoritativenoyes / yesrefused0
pns.aip.de 141.33.207.16NOERROR, 13 ms, authoritativenoyes / yesALLOWED (1051 records)-

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: dns-2.dfn.de: "0"; dns-3.dfn.de: "0".
    #17
  • ✗
    Zone transfer allowed
    These nameservers send the complete zone to anyone who asks (AXFR), exposing all host names: pns.aip.de (141.33.207.16): 1051 records. Restrict zone transfers to your secondary servers.
    #18
  • ✓ 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 2026101401 · primary pns.aip.de

Found

Primary (MNAME)
pns.aip.de
Contact (RNAME)
ip-admin.aip.de
Serial
2026101401
Refresh / retry
28800 s / 7200 s
Expire
604800 s
Negative TTL
7200 s

Serial per nameserver

NameserverSerial
dns-2.dfn.de (193.174.75.54)2026101401
dns-2.dfn.de (2001:638:d:b102::1)2026101401
dns-3.dfn.de (193.174.75.58)2026101401
dns-3.dfn.de (2001:638:d:b103::1)2026101401
pns.aip.de (141.33.207.16)2026101401

Checks

  • ✓ Serial 2026101401 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 8h, retry 2h, expire 7d, negative TTL 2h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver pns.aip.de is one of the listed nameservers.
  • ✓ Contact ip-admin@aip.de #25
    The SOA RNAME ip-admin.aip.de means ip-admin@aip.de.
  • ✓ Date-based serial #26
    The serial 2026101401 follows the YYYYMMDDnn convention (2026-10-14).

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

12 records at the apex

Found

Read from
193.174.75.54:53
TypeValueTTL
SOApns.aip.de. ip-admin.aip.de. 2026101401 28800 7200 604800 72003600
NSdns-2.dfn.de.3600
NSpns.aip.de.3600
NSdns-3.dfn.de.3600
A141.33.207.2193600
MX10 a2271.mx.srv.dfn.de.3600
MX10 c2271.mx.srv.dfn.de.3600
MX10 b2271.mx.srv.dfn.de.3600
TXT"apple-domain-verification=yFArMn4kQwlHLo1s"3600
TXT"HARICA-aqv58TRCp1B4Pu8XEJM"3600
TXT"v=spf1 mx ip4:141.33.160.30 ip4:141.33.160.31 ip4:141.33.160.3 ip4:141.33.160.26 -all"3600
TXT"MS=4CDF836D33216B2FEC6623226CC1D2C8DC27F1A1"3600

Checks

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