ntk.nl

Checked 22 October 2026, 15:01 UTC · via 8.8.8.8
!Passed with warnings
19 passed 3 warnings 0 failed 7 info

Registration

info

.nl country-code

Found

TLD
.nl (country-code)
ICANN policies apply
no
Lookup error: https://rdap.sidn.nl/domain/ntk.nl returned HTTP 429

Checks

  • i
    .nl 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
    .nl is delegated in the root zone and DNSSEC-signed.
  • i
    Could not be checked
    The RDAP lookup failed, so this could not be checked: https://rdap.sidn.nl/domain/ntk.nl returned HTTP 429
    #3

Delegation

info

brit.ns.cloudflare.com, seth.ns.cloudflare.com

Found

Parent zone
nl
Delegation from
ns1.dns.nl (194.0.28.53)
NS at the parent
brit.ns.cloudflare.com, seth.ns.cloudflare.com
NS in the zone
brit.ns.cloudflare.com, seth.ns.cloudflare.com
NameserverAddressesNetwork (AS)Glue
brit.ns.cloudflare.com172.64.32.78 108.162.192.78 173.245.58.78 2606:4700:50::adf5:3a4e 2803:f800:50::6ca2:c04e 2a06:98c1:50::ac40:204eAS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US-
seth.ns.cloudflare.com172.64.33.142 108.162.193.142 173.245.59.142 2606:4700:58::adf5:3b8e 2803:f800:50::6ca2:c18e 2a06:98c1:50::ac40:218eAS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US AS13335 CLOUDFLARENET - Cloudflare, Inc., US-

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: brit.ns.cloudflare.com, seth.ns.cloudflare.com.
    #6
  • ✓ 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 6 IPv4 /24s and 4 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS13335 (CLOUDFLARENET - Cloudflare, Inc., US): 12 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 .com
    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
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

warn

12 of 12 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
brit.ns.cloudflare.com 172.64.32.78NOERROR, 16 ms, authoritativenoyes / yesrefused2026.10.2
brit.ns.cloudflare.com 108.162.192.78NOERROR, 16 ms, authoritativenoyes / yesrefused2026.10.2
brit.ns.cloudflare.com 173.245.58.78NOERROR, 15 ms, authoritativenoyes / yesrefused2026.10.2
brit.ns.cloudflare.com 2606:4700:50::adf5:3a4eNOERROR, 14 ms, authoritativenoyes / yesrefused2026.10.2
brit.ns.cloudflare.com 2803:f800:50::6ca2:c04eNOERROR, 15 ms, authoritativenoyes / yesrefused2026.10.2
brit.ns.cloudflare.com 2a06:98c1:50::ac40:204eNOERROR, 16 ms, authoritativenoyes / yesrefused2026.10.2
seth.ns.cloudflare.com 172.64.33.142NOERROR, 16 ms, authoritativenoyes / yesrefused2026.10.2
seth.ns.cloudflare.com 108.162.193.142NOERROR, 15 ms, authoritativenoyes / yesrefused2026.10.2
seth.ns.cloudflare.com 173.245.59.142NOERROR, 18 ms, authoritativenoyes / yesrefused2026.10.2
seth.ns.cloudflare.com 2606:4700:58::adf5:3b8eNOERROR, 16 ms, authoritativenoyes / yesrefused2026.10.2
seth.ns.cloudflare.com 2803:f800:50::6ca2:c18eNOERROR, 16 ms, authoritativenoyes / yesrefused2026.10.2
seth.ns.cloudflare.com 2a06:98c1:50::ac40:218eNOERROR, 16 ms, authoritativenoyes / yesrefused2026.10.2

Checks

  • ✓ All respond #14
    All 12 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: brit.ns.cloudflare.com: "2026.10.2"; seth.ns.cloudflare.com: "2026.10.2". 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 2417619610 · primary brit.ns.cloudflare.com

Found

Primary (MNAME)
brit.ns.cloudflare.com
Contact (RNAME)
dns.cloudflare.com
Serial
2417619610
Refresh / retry
10000 s / 2400 s
Expire
604800 s
Negative TTL
1800 s

Serial per nameserver

NameserverSerial
brit.ns.cloudflare.com (172.64.32.78)2417619610
brit.ns.cloudflare.com (108.162.192.78)2417619610
brit.ns.cloudflare.com (173.245.58.78)2417619610
brit.ns.cloudflare.com (2606:4700:50::adf5:3a4e)2417619610
brit.ns.cloudflare.com (2803:f800:50::6ca2:c04e)2417619610
brit.ns.cloudflare.com (2a06:98c1:50::ac40:204e)2417619610
seth.ns.cloudflare.com (172.64.33.142)2417619610
seth.ns.cloudflare.com (108.162.193.142)2417619610
seth.ns.cloudflare.com (173.245.59.142)2417619610
seth.ns.cloudflare.com (2606:4700:58::adf5:3b8e)2417619610
seth.ns.cloudflare.com (2803:f800:50::6ca2:c18e)2417619610
seth.ns.cloudflare.com (2a06:98c1:50::ac40:218e)2417619610

Checks

  • ✓ Serial 2417619610 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 2h46m40s, retry 40m, expire 7d, negative TTL 30m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver brit.ns.cloudflare.com is one of the listed nameservers.
  • ✓ Contact dns@cloudflare.com #25
    The SOA RNAME dns.cloudflare.com means dns@cloudflare.com.
  • ✓ Timestamp serial #26
    The serial 2417619610 is a Unix timestamp (2046-08-11 17:00 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

warn

10 records at the apex

Found

Read from
172.64.32.78:53
TypeValueTTL
SOAbrit.ns.cloudflare.com. dns.cloudflare.com. 2417619610 10000 2400 604800 18001800
NSbrit.ns.cloudflare.com.86400
NSseth.ns.cloudflare.com.86400
A34.76.90.150300
MX10 ntk-nl.mail.protection.outlook.com.120
TXT"MS=ms14458817"300
TXT"dc9371e6-69bb-4e44-857d-b779cfafbdad"300
TXT"google-site-verification=3GPc4q0XVOv-5yDR98Hiwqs-q4v_s0iki2WvZ1eqAlU"300
TXT"google-site-verification=L5KPMmXED_PkClj8HIW9ubm-7mHxNq8gRidQYR17F9Q"300
TXT"v=spf1 a:o1.delivery.ntk.nl include:delivery.ntk.nl a:mail.ntk.nl include:spf.mtasv.net include:servers.mcsv.net include:spf.protection.outlook.com include:_spf.exactonline.nl include:spf.eu.ex" "claimer.net -all"300

Checks

  • !
    Very low TTLs
    These records have a TTL below 5m, causing extra queries and slower lookups: MX (2m). Low TTLs are useful just before a planned change. The NS TTL at the parent is 1h and in the zone 1d; resolvers may use either.
    #32
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • i
    Wildcard record
    A random name under the zone resolves, so there is a wildcard (*) record. Typos and non-existent hosts resolve too, which can confuse mail and certificate checks.
    #34
  • 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