boerse-frankfurt.de

Checked 21 October 2026, 21:50 UTC · via 8.8.8.8
✗Problems found
23 passed 2 warnings 1 failed 3 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

pass

a.dbgdns.de, a.dbgdns.lu, b.dbgdns.de, b.dbgdns.lu

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
a.dbgdns.de, a.dbgdns.lu, b.dbgdns.de, b.dbgdns.lu
NS in the zone
a.dbgdns.de, a.dbgdns.lu, b.dbgdns.de, b.dbgdns.lu
NameserverAddressesNetwork (AS)Glue
a.dbgdns.de193.29.87.12 2a00:7440:4:287::1111:12AS12625 AS12625 - Deutsche Boerse AG, DE AS12625 AS12625 - Deutsche Boerse AG, DE193.29.87.12 2a00:7440:4:287::1111:12
a.dbgdns.lu194.36.237.12 2a03:98c0:14:2504::1111:12AS15814 AS15814 - Clearstream Services S.A., LU AS15814 AS15814 - Clearstream Services S.A., LU-
b.dbgdns.de194.36.237.44 2a03:98c0:14:2504::2222:44AS15814 AS15814 - Clearstream Services S.A., LU AS15814 AS15814 - Clearstream Services S.A., LU194.36.237.44 2a03:98c0:14:2504::2222:44
b.dbgdns.lu193.29.87.44 2a00:7440:4:287::2222:44AS12625 AS12625 - Deutsche Boerse AG, DE AS12625 AS12625 - Deutsche Boerse AG, DE-

Checks

  • ✓ 4 nameservers #6
    Delegated to a.dbgdns.de, a.dbgdns.lu, b.dbgdns.de, b.dbgdns.lu.
  • ✓ 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 2 IPv4 /24s and 2 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS12625 (AS12625 - Deutsche Boerse AG, DE): 4 addresses; AS15814 (AS15814 - Clearstream Services S.A., LU): 4 addresses.
  • ✓ Nameserver names under 2 TLDs #12
    Nameserver names use the TLDs .de, .lu.
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

fail

6 of 8 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
a.dbgdns.de 193.29.87.12NOERROR, 6 ms, authoritativenoyes / yesrefused-
a.dbgdns.de 2a00:7440:4:287::1111:12NOERROR, 6 ms, authoritativenoyes / yesrefused-
a.dbgdns.lu 194.36.237.12NOERROR, 10 ms, authoritativenoyes / yesrefused-
a.dbgdns.lu 2a03:98c0:14:2504::1111:12no responsenono / no--
b.dbgdns.de 194.36.237.44NOERROR, 13 ms, authoritativenoyes / yesrefused-
b.dbgdns.de 2a03:98c0:14:2504::2222:44no responsenono / no--
b.dbgdns.lu 193.29.87.44NOERROR, 6 ms, authoritativenoyes / yesrefused-
b.dbgdns.lu 2a00:7440:4:287::2222:44NOERROR, 6 ms, authoritativenoyes / yesrefused-

Checks

  • ✗
    Nameservers not responding
    These addresses did not answer, so resolvers waste time on timeouts: a.dbgdns.lu (2a03:98c0:14:2504::1111:12): read udp [2a01:4f8:1c1c:eebf::1]:45594->[2a03:98c0:14:2504::1111:12]:53: i/o timeout; b.dbgdns.de (2a03:98c0:14:2504::2222:44): read udp [2a01:4f8:1c1c:eebf::1]:54527->[2a03:98c0:14:2504::2222:44]:53: i/o timeout.
    #14
  • ✓ 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 2025052710 · primary a.dbgdns.de

Found

Primary (MNAME)
a.dbgdns.de
Contact (RNAME)
hostmaster.deutsche-boerse.com
Serial
2025052710
Refresh / retry
14400 s / 3600 s
Expire
1209600 s
Negative TTL
180 s

Serial per nameserver

NameserverSerial
a.dbgdns.de (193.29.87.12)2025052710
a.dbgdns.de (2a00:7440:4:287::1111:12)2025052710
a.dbgdns.lu (194.36.237.12)2025052710
b.dbgdns.de (194.36.237.44)2025052710
b.dbgdns.lu (193.29.87.44)2025052710
b.dbgdns.lu (2a00:7440:4:287::2222:44)2025052710

Checks

  • ✓ Serial 2025052710 everywhere #22
    All nameservers serve the same version of the zone.
  • !
    Unusual SOA timers
    negative caching TTL (minimum) 3m is outside 5m–1d (RFC 2308 recommends 1–3 hours). Current values: refresh 4h, retry 1h, expire 14d, negative TTL 3m.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver a.dbgdns.de is one of the listed nameservers.
  • ✓ Contact hostmaster@deutsche-boerse.com #25
    The SOA RNAME hostmaster.deutsche-boerse.com means hostmaster@deutsche-boerse.com.
  • ✓ Date-based serial #26
    The serial 2025052710 follows the YYYYMMDDnn convention (2025-05-27).

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

14 records at the apex

Found

Read from
193.29.87.12:53
TypeValueTTL
SOAa.dbgdns.de. hostmaster.deutsche-boerse.com. 2025052710 14400 3600 1209600 1803600
NSb.dbgdns.lu.3600
NSa.dbgdns.lu.3600
NSb.dbgdns.de.3600
NSa.dbgdns.de.3600
A82.97.136.1013600
MX100 mail14.clearstream.com.3600
MX0 mail17.deutsche-boerse.com.3600
MX0 mail16.deutsche-boerse.com.3600
MX100 mail15.clearstream.com.3600
TXT"40kb2rsr0yg60kcy5q991cbls73wdc0g"3600
TXT"rovag_verification_token=E8735C7773584C0095F119936152A009"3600
TXT"google-site-verification=urb2ZDGDv9vThMQcMu_5uPf28ORDW36XOrzGC8bNGAA."3600
TXT"v=spf1 mx ip4:82.97.160.225/32 include:dbgmail.net -all"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