mpie.de

Checked 21 October 2026, 23:30 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

dns-1.dfn.de, dns1.gwdg.de, dns2.gwdg.de, dns3.gwdg.de, rzdns1.mpie-duesseldorf.mpg.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-1.dfn.de, dns1.gwdg.de, dns2.gwdg.de, dns3.gwdg.de, rzdns1.mpie-duesseldorf.mpg.de
NS in the zone
dns-1.dfn.de, dns1.gwdg.de, dns2.gwdg.de, dns3.gwdg.de, rzdns1.mpie-duesseldorf.mpg.de
NameserverAddressesNetwork (AS)Glue
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-
dns1.gwdg.de134.76.33.41 2a06:93c7:e1::1AS207592 GOENET - Gesellschaft fuer wissenschaftliche Datenverarbeitung mbH, Goettingen, DE AS207592 GOENET - Gesellschaft fuer wissenschaftliche Datenverarbeitung mbH, Goettingen, DE134.76.33.41 2a06:93c7:e1::1
dns2.gwdg.de134.76.33.42 2a06:93c7:e2::1AS207592 GOENET - Gesellschaft fuer wissenschaftliche Datenverarbeitung mbH, Goettingen, DE AS207592 GOENET - Gesellschaft fuer wissenschaftliche Datenverarbeitung mbH, Goettingen, DE134.76.33.42 2a06:93c7:e2::1
dns3.gwdg.de193.175.210.140AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE193.175.210.140
rzdns1.mpie-duesseldorf.mpg.de193.175.131.226AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-

Checks

  • ✓ 5 nameservers #6
    Delegated to dns-1.dfn.de, dns1.gwdg.de, dns2.gwdg.de, dns3.gwdg.de, rzdns1.mpie-duesseldorf.mpg.de.
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • ✓ No glue needed #8
    All nameservers are outside the zone, so no glue records are needed.
  • ✓ 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 4 IPv4 /24s and 3 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS207592 (GOENET - Gesellschaft fuer wissenschaftliche Datenverarbeitung mbH, Goettingen, DE): 4 addresses; AS680 (DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE): 4 addresses.
  • 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: dns3.gwdg.de, rzdns1.mpie-duesseldorf.mpg.de.
    #13

Nameservers

info

8 of 8 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns-1.dfn.de 193.174.75.50NOERROR, 12 ms, authoritativenoyes / yesrefused0
dns-1.dfn.de 2001:638:d:b101::1NOERROR, 12 ms, authoritativenoyes / yesrefused0
dns1.gwdg.de 134.76.33.41NOERROR, 8 ms, authoritativenoyes / yesrefused-
dns1.gwdg.de 2a06:93c7:e1::1NOERROR, 8 ms, authoritativenoyes / yesrefused-
dns2.gwdg.de 134.76.33.42NOERROR, 7 ms, authoritativenoyes / yesrefused-
dns2.gwdg.de 2a06:93c7:e2::1NOERROR, 8 ms, authoritativenoyes / yesrefused-
dns3.gwdg.de 193.175.210.140NOERROR, 13 ms, authoritativenoyes / yesrefused-
rzdns1.mpie-duesseldorf.mpg.de 193.175.131.226NOERROR, 8 ms, authoritativenoyes / yesrefused-

Checks

  • ✓ All respond #14
    All 8 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 3011030588 · primary rzdns1.mpie-duesseldorf.mpg.de

Found

Primary (MNAME)
rzdns1.mpie-duesseldorf.mpg.de
Contact (RNAME)
hostmaster.mpie.de
Serial
3011030588
Refresh / retry
10800 s / 3600 s
Expire
2419200 s
Negative TTL
900 s

Serial per nameserver

NameserverSerial
dns-1.dfn.de (193.174.75.50)3011030588
dns-1.dfn.de (2001:638:d:b101::1)3011030588
dns1.gwdg.de (134.76.33.41)3011030588
dns1.gwdg.de (2a06:93c7:e1::1)3011030588
dns2.gwdg.de (134.76.33.42)3011030588
dns2.gwdg.de (2a06:93c7:e2::1)3011030588
dns3.gwdg.de (193.175.210.140)3011030588
rzdns1.mpie-duesseldorf.mpg.de (193.175.131.226)3011030588

Checks

  • ✓ Serial 3011030588 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 28d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver rzdns1.mpie-duesseldorf.mpg.de is one of the listed nameservers.
  • ✓ Contact hostmaster@mpie.de #25
    The SOA RNAME hostmaster.mpie.de means hostmaster@mpie.de.
  • ✓ Timestamp serial #26
    The serial 3011030588 is a Unix timestamp (2065-05-31 21:23 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

13 records at the apex

Found

Read from
193.174.75.50:53
TypeValueTTL
SOArzdns1.mpie-duesseldorf.mpg.de. hostmaster.mpie.de. 3011030588 10800 3600 2419200 90028800
NSdns2.gwdg.de.28800
NSdns1.gwdg.de.28800
NSdns3.gwdg.de.28800
NSdns-1.dfn.de.28800
NSrzdns1.mpie-duesseldorf.mpg.de.28800
MX50 gate236.mpie.de.300
MX40 gate237.mpie.de.300
MX7 gate235.mpie.de.300
TXT"MS=ms46270984"28800
TXT"anthropic-domain-verification-j68h5j=6joeXxisGMI43CaD08QYomHrW"28800
TXT"v=spf1 mx ip4:193.175.131.225/28 include:spf.smtp.net ip4:134.76.31.246 -all"28800
TXT"cisco-ci-domain-verification=51a0cdc061d0174139d96b8a51bfc97919721c59537c759753b55dd09a9c3cd1"28800

Checks

  • ✓ TTLs within range #32
    TTLs: MX 5m, 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