booklooker.de

Checked 21 October 2026, 21:50 UTC · via 8.8.8.8
!Passed with warnings
23 passed 3 warnings 0 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

warn

ns1.booklooker.de, ns2.booklooker.de, ns3.booklooker.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns1.booklooker.de, ns2.booklooker.de, ns3.booklooker.de
NS in the zone
ns1.booklooker.de, ns2.booklooker.de, ns3.booklooker.de
NameserverAddressesNetwork (AS)Glue
ns1.booklooker.de78.138.114.79AS61157 PLUSSERVER-ASN1 - PlusServer GmbH, DE78.138.114.79
ns2.booklooker.de195.8.253.225AS8820 TAL-DE - tal.de GmbH, DE195.8.253.225
ns3.booklooker.de78.138.114.72AS61157 PLUSSERVER-ASN1 - PlusServer GmbH, DE78.138.114.72

Checks

  • ✓ 3 nameservers #6
    Delegated to ns1.booklooker.de, ns2.booklooker.de, ns3.booklooker.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: ns1.booklooker.de, ns2.booklooker.de, ns3.booklooker.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 2 IPv4 /24s and 0 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS61157 (PLUSSERVER-ASN1 - PlusServer GmbH, DE): 2 addresses; AS8820 (TAL-DE - tal.de GmbH, DE): 1 address.
  • 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
  • !
    No IPv6
    None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.
    #13

Nameservers

warn

3 of 3 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns1.booklooker.de 78.138.114.79NOERROR, 8 ms, authoritativenoyes / yesrefused9.18.39-0ubuntu0.22.04.7-Ubuntu
ns2.booklooker.de 195.8.253.225NOERROR, 8 ms, authoritativenoyes / yesrefused-
ns3.booklooker.de 78.138.114.72NOERROR, 8 ms, authoritativenoyes / yesrefused-

Checks

  • ✓ All respond #14
    All 3 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.
  • !
    Software version disclosed
    These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: ns1.booklooker.de: "9.18.39-0ubuntu0.22.04.7-Ubuntu". Hide or replace the version string.
    #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 2026042102 · primary ns1.booklooker.de

Found

Primary (MNAME)
ns1.booklooker.de
Contact (RNAME)
root.booklooker.de
Serial
2026042102
Refresh / retry
3600 s / 1200 s
Expire
1209600 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
ns1.booklooker.de (78.138.114.79)2026042102
ns2.booklooker.de (195.8.253.225)2026042102
ns3.booklooker.de (78.138.114.72)2026042102

Checks

  • ✓ Serial 2026042102 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 1h, retry 20m, expire 14d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.booklooker.de is one of the listed nameservers.
  • ✓ Contact root@booklooker.de #25
    The SOA RNAME root.booklooker.de means root@booklooker.de.
  • ✓ Date-based serial #26
    The serial 2026042102 follows the YYYYMMDDnn convention (2026-04-21).

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

pass

10 records at the apex

Found

Read from
78.138.114.79:53
TypeValueTTL
SOAns1.booklooker.de. root.booklooker.de. 2026042102 3600 1200 1209600 8640086400
NSns1.booklooker.de.86400
NSns2.booklooker.de.86400
NSns3.booklooker.de.86400
A80.90.17.20186400
MX10 mail2.booklooker.de.86400
MX20 mail.booklooker.de.86400
TXT"google-site-verification=BxypfCMv3fwvcj-5gq9JBSdZnG36Ui8rdjfsKce0lLU"86400
TXT"v=spf1 a mx a:mail.booklooker.de a:heine.booklooker.de a:hesse.booklooker.de a:boell.booklooker.de -all"86400
CAA0 issuewild "sectigo.com"86400

Checks

  • ✓ TTLs within range #32
    TTLs: A 1d, MX 1d, NS 1d.
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • ✓ No wildcard #34
    Names that don't exist return NXDOMAIN.
  • ✓ CAA restricts issuance #35
    Certificates may be issued by: sectigo.com.