dw-world.de

Checked 21 October 2026, 22:15 UTC · via 8.8.8.8
!Passed with warnings
20 passed 3 warnings 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

warn

dns3.netcologne.de, dns4.netcologne.de, dns5.netcologne.de, voltaire.dwelle.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns3.netcologne.de, dns4.netcologne.de, dns5.netcologne.de, voltaire.dwelle.de
NS in the zone
dns3.netcologne.de, dns4.netcologne.de, dns5.netcologne.de, voltaire.dwelle.de
NameserverAddressesNetwork (AS)Glue
dns3.netcologne.de213.196.239.187 2001:4dd0:100:1029:53:3:0:3AS8422 NETCOLOGNE - NetCologne Gesellschaft fur Telekommunikation mbH, DE AS8422 NETCOLOGNE - NetCologne Gesellschaft fur Telekommunikation mbH, DE-
dns4.netcologne.de195.14.247.116 2001:4dd0:100:4220:53:4:0:4AS8422 NETCOLOGNE - NetCologne Gesellschaft fur Telekommunikation mbH, DE AS8422 NETCOLOGNE - NetCologne Gesellschaft fur Telekommunikation mbH, DE-
dns5.netcologne.de134.95.100.211AS5520 UNI-KOELN - Universitaet zu Koeln, DE-
voltaire.dwelle.de194.55.30.40 194.55.26.40AS200777 Deutsche-Welle - Deutsche Welle Anstalt des Oeffentlichen Rechts, DE AS200777 Deutsche-Welle - Deutsche Welle Anstalt des Oeffentlichen Rechts, DE194.55.30.40

Checks

  • ✓ 4 nameservers #6
    Delegated to dns3.netcologne.de, dns4.netcologne.de, dns5.netcologne.de, voltaire.dwelle.de.
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • !
    Glue differs from the zone
    The addresses at the parent (glue) differ from the addresses in the zone: voltaire.dwelle.de (glue 194.55.30.40, zone 194.55.30.40, 194.55.26.40). Update the glue at your registrar.
    #8
  • ✓ 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 2001:4dd0:100::/48, while the other address family is spread over several networks.
    #10
  • ✓ 3 autonomous systems #11
    The nameservers are spread over: AS200777 (Deutsche-Welle - Deutsche Welle Anstalt des Oeffentlichen Rechts, DE): 2 addresses; AS5520 (UNI-KOELN - Universitaet zu Koeln, DE): 1 address; AS8422 (NETCOLOGNE - NetCologne Gesellschaft fur Telekommunikation mbH, 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: dns5.netcologne.de, voltaire.dwelle.de.
    #13

Nameservers

pass

7 of 7 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns3.netcologne.de 213.196.239.187NOERROR, 7 ms, authoritativenoyes / yesrefused-
dns3.netcologne.de 2001:4dd0:100:1029:53:3:0:3NOERROR, 7 ms, authoritativenoyes / yesrefused-
dns4.netcologne.de 195.14.247.116NOERROR, 7 ms, authoritativenoyes / yesrefused-
dns4.netcologne.de 2001:4dd0:100:4220:53:4:0:4NOERROR, 6 ms, authoritativenoyes / yesrefused-
dns5.netcologne.de 134.95.100.211NOERROR, 11 ms, authoritativenoyes / yesrefused-
voltaire.dwelle.de 194.55.30.40NOERROR, 14 ms, authoritativenoyes / yesrefused-
voltaire.dwelle.de 194.55.26.40NOERROR, 15 ms, authoritativenoyes / yesrefused-

Checks

  • ✓ All respond #14
    All 7 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.
  • ✓ No version disclosed #17
    The nameservers don't reveal their software version.
  • ✓ 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

warn

serial 2026031901 · primary voltaire.dwelle.de

Found

Primary (MNAME)
voltaire.dwelle.de
Contact (RNAME)
arno.wagner.dw.de
Serial
2026031901
Refresh / retry
1800 s / 3600 s
Expire
3024000 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns3.netcologne.de (213.196.239.187)2026031901
dns3.netcologne.de (2001:4dd0:100:1029:53:3:0:3)2026031901
dns4.netcologne.de (195.14.247.116)2026031901
dns4.netcologne.de (2001:4dd0:100:4220:53:4:0:4)2026031901
dns5.netcologne.de (134.95.100.211)2026031901
voltaire.dwelle.de (194.55.30.40)2026031901
voltaire.dwelle.de (194.55.26.40)2026031901

Checks

  • ✓ Serial 2026031901 everywhere #22
    All nameservers serve the same version of the zone.
  • !
    Unusual SOA timers
    retry 1h should be shorter than refresh 30m. Current values: refresh 30m, retry 1h, expire 35d, negative TTL 1h.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver voltaire.dwelle.de is one of the listed nameservers.
  • ✓ Contact arno@wagner.dw.de #25
    The SOA RNAME arno.wagner.dw.de means arno@wagner.dw.de.
  • ✓ Date-based serial #26
    The serial 2026031901 follows the YYYYMMDDnn convention (2026-03-19).

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

9 records at the apex

Found

Read from
213.196.239.187:53
TypeValueTTL
SOAvoltaire.dwelle.de. arno.wagner.dw.de. 2026031901 1800 3600 3024000 36003600
NSdns5.netcologne.de.3600
NSvoltaire.dwelle.de.3600
NSdns3.netcologne.de.3600
NSdns4.netcologne.de.3600
A194.55.30.467200
A194.55.26.467200
MX0 .3600
TXT"v=spf1 -all"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 2h, 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