trc-leiden.nl

Checked 22 October 2026, 16:40 UTC · via 8.8.8.8
!Passed with warnings
22 passed 3 warnings 0 failed 4 info

Registration

info

.nl country-code

Found

TLD
.nl (country-code)
ICANN policies apply
no
Lookup error: https://rdap.sidn.nl/domain/trc-leiden.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/trc-leiden.nl returned HTTP 429
    #3

Delegation

warn

ns1.serverhostgroup.com, ns2.serverhostgroup.com, ns3.serverhostgroup.com

Found

Parent zone
nl
Delegation from
ns1.dns.nl (194.0.28.53)
NS at the parent
ns1.serverhostgroup.com, ns2.serverhostgroup.com, ns3.serverhostgroup.com
NS in the zone
ns1.serverhostgroup.com, ns2.serverhostgroup.com, ns3.serverhostgroup.com
NameserverAddressesNetwork (AS)Glue
ns1.serverhostgroup.com104.236.38.47AS14061 DIGITALOCEAN-ASN - DigitalOcean, LLC, US-
ns2.serverhostgroup.com46.101.214.99AS14061 DIGITALOCEAN-ASN - DigitalOcean, LLC, US-
ns3.serverhostgroup.com141.164.45.163AS20473 AS-VULTR - The Constant Company, LLC, US-

Checks

  • ✓ 3 nameservers #6
    Delegated to ns1.serverhostgroup.com, ns2.serverhostgroup.com, ns3.serverhostgroup.com.
  • ✓ 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 3 IPv4 /24s and 0 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS14061 (DIGITALOCEAN-ASN - DigitalOcean, LLC, US): 2 addresses; AS20473 (AS-VULTR - The Constant Company, LLC, US): 1 address.
  • 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
  • !
    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.serverhostgroup.com 104.236.38.47NOERROR, 93 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.9.17 (built Aug 10 2026 11:51:37 by root@bh-centos-8.dev.cpanel.net)
ns2.serverhostgroup.com 46.101.214.99NOERROR, 4 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 5.1.4 (built Aug 10 2026 13:38:30 by root@bh-centos-8.dev.cpanel.net)
ns3.serverhostgroup.com 141.164.45.163NOERROR, 226 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 5.1.4 (built Aug 10 2026 00:00:00 by root@bh-centos-9.dev.cpanel.net)

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.serverhostgroup.com: "PowerDNS Authoritative Server 4.9.17 (built Aug 10 2026 11:51:37 by root@bh-centos-8.dev.cpanel.net)"; ns2.serverhostgroup.com: "PowerDNS Authoritative Server 5.1.4 (built Aug 10 2026 13:38:30 by root@bh-centos-8.dev.cpanel.net)"; ns3.serverhostgroup.com: "PowerDNS Authoritative Server 5.1.4 (built Aug 10 2026 00:00:00 by root@bh-centos-9.dev.cpanel.net)". 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 2026092101 · primary ns1.serverhostgroup.com

Found

Primary (MNAME)
ns1.serverhostgroup.com
Contact (RNAME)
info.joostkolkman.nl
Serial
2026092101
Refresh / retry
3600 s / 1800 s
Expire
1209600 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
ns1.serverhostgroup.com (104.236.38.47)2026092101
ns2.serverhostgroup.com (46.101.214.99)2026092101
ns3.serverhostgroup.com (141.164.45.163)2026092101

Checks

  • ✓ Serial 2026092101 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 1h, retry 30m, expire 14d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.serverhostgroup.com is one of the listed nameservers.
  • ✓ Contact info@joostkolkman.nl #25
    The SOA RNAME info.joostkolkman.nl means info@joostkolkman.nl.
  • ✓ Date-based serial #26
    The serial 2026092101 follows the YYYYMMDDnn convention (2026-09-21).

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

info

7 records at the apex

Found

Read from
104.236.38.47:53
TypeValueTTL
SOAns1.serverhostgroup.com. info.joostkolkman.nl. 2026092101 3600 1800 1209600 8640086400
NSns2.serverhostgroup.com.86400
NSns1.serverhostgroup.com.86400
NSns3.serverhostgroup.com.86400
A57.129.90.1514400
MX0 trc-leiden.nl.14400
TXT"v=spf1 a mx include:relay.mailchannels.net ?all"14400

Checks

  • ✓ TTLs within range #32
    TTLs: A 4h, MX 4h, NS 1d. The NS TTL at the parent is 1h and in the zone 1d; 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