radboudumc.nl

Checked 21 October 2026, 21:24 UTC · via 8.8.8.8
!Passed with warnings
27 passed 1 warning 0 failed 7 info

Registration

info

.nl country-code · SURF B.V.

Found

TLD
.nl (country-code)
ICANN policies apply
no
Registrar
SURF B.V.
Registered
20 November 2008
Last changed
16 March 2026
Status
active
Registry nameservers
ns1.surfnet.nl, ns1.zurich.surf.net, umcdns05.umcn.nl
RDAP server
https://rdap.sidn.nl/

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
    Expiry date not published
    The registry does not publish the expiry date in RDAP. Check it with your registrar.
    #3
  • i
    No transfer lock
    The domain has no transfer lock (status: active). A registrar lock protects against unauthorized transfers.
    #4
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

info

ns1.surfnet.nl, ns1.zurich.surf.net, umcdns05.umcn.nl

Found

Parent zone
nl
Delegation from
ns1.dns.nl (194.0.28.53)
NS at the parent
ns1.surfnet.nl, ns1.zurich.surf.net, umcdns05.umcn.nl
NS in the zone
ns1.surfnet.nl, ns1.zurich.surf.net, umcdns05.umcn.nl
NameserverAddressesNetwork (AS)Glue
ns1.surfnet.nl192.87.106.101 2001:610:1:800a:192:87:106:101AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL192.87.106.101 2001:610:1:800a:192:87:106:101
ns1.zurich.surf.net195.176.255.9 2001:620:0:9::1103AS559 Switch - SWITCH, CH AS559 Switch - SWITCH, CH-
umcdns05.umcn.nl131.174.165.10AS1103 SURFNET-NL - SURF B.V., NL131.174.165.10

Checks

  • ✓ 3 nameservers #6
    Delegated to ns1.surfnet.nl, ns1.zurich.surf.net, umcdns05.umcn.nl.
  • ✓ 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 2 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS1103 (SURFNET-NL - SURF B.V., NL): 3 addresses; AS559 (Switch - SWITCH, CH): 2 addresses.
  • ✓ Nameserver names under 2 TLDs #12
    Nameserver names use the TLDs .net, .nl.
  • i
    Partly IPv6
    These nameservers have no IPv6 address: umcdns05.umcn.nl.
    #13

Nameservers

info

5 of 5 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns1.surfnet.nl 192.87.106.101NOERROR, 9 ms, authoritativenoyes / yesrefusedThis is a SURFnet nameserver - dns-beheer@surfnet.nl
ns1.surfnet.nl 2001:610:1:800a:192:87:106:101NOERROR, 10 ms, authoritativenoyes / yesrefusedThis is a SURFnet nameserver - dns-beheer@surfnet.nl
ns1.zurich.surf.net 195.176.255.9NOERROR, 11 ms, authoritativenoyes / yesrefusedThis is a SURFnet nameserver - dns-beheer@surf.nl
ns1.zurich.surf.net 2001:620:0:9::1103NOERROR, 10 ms, authoritativenoyes / yesrefusedThis is a SURFnet nameserver - dns-beheer@surf.nl
umcdns05.umcn.nl 131.174.165.10NOERROR, 13 ms, authoritativenoyes / yesrefused-

Checks

  • ✓ All respond #14
    All 5 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.
  • i
    Identifying string disclosed
    These nameservers answer version queries with a string that is not a version number: ns1.surfnet.nl: "This is a SURFnet nameserver - dns-beheer@surfnet.nl"; ns1.zurich.surf.net: "This is a SURFnet nameserver - dns-beheer@surf.nl".
    #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 2019146679 · primary umcdns05.umcn.nl

Found

Primary (MNAME)
umcdns05.umcn.nl
Contact (RNAME)
netwerkbeheerict.radboudumc.nl
Serial
2019146679
Refresh / retry
10800 s / 1080 s
Expire
2419200 s
Negative TTL
900 s

Serial per nameserver

NameserverSerial
ns1.surfnet.nl (192.87.106.101)2019146679
ns1.surfnet.nl (2001:610:1:800a:192:87:106:101)2019146679
ns1.zurich.surf.net (195.176.255.9)2019146679
ns1.zurich.surf.net (2001:620:0:9::1103)2019146679
umcdns05.umcn.nl (131.174.165.10)2019146679

Checks

  • ✓ Serial 2019146679 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 18m, expire 28d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver umcdns05.umcn.nl is one of the listed nameservers.
  • ✓ Contact netwerkbeheerict@radboudumc.nl #25
    The SOA RNAME netwerkbeheerict.radboudumc.nl means netwerkbeheerict@radboudumc.nl.
  • ✓ Timestamp serial #26
    The serial 2019146679 is a Unix timestamp (2033-12-25 18:04 UTC).

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver
yes
Denial of existence
NSEC3
NSEC3
10 iterations, 8-byte salt
Signatures valid until
25 October 2026

DS at the parent

Key tagAlgorithmDigestMatches a key
18709RSASHA512 (10)SHA256 CFBFBD3C07A8E6C0…yes

DNSKEY in the zone

Key tagRoleAlgorithm
18709KSK (257)RSASHA512 (10)
38433KSK (257)RSASHA512 (10)
55440ZSK (256)RSASHA512 (10)
23093ZSK (256)RSASHA512 (10)
30921ZSK (256)RSASHA512 (10)
56568ZSK (256)RSASHA512 (10)

Checks

  • ✓ Signed and validated #27
    The zone is signed, the parent publishes a DS record, and the resolver validates the answers.
  • ✓ DS matches a key #28
    The DS record at the parent matches a key in the zone: key tag 18709 (SHA256).
  • ✓ Modern algorithms #29
    Key algorithms: RSASHA512 (10).
  • ✓ Short-lived signatures (online signing) #30
    Signatures are valid for 96h0m0s and created on demand; the current one was made at 2026-10-21 14:37 UTC and expires at 2026-10-25 14:45 UTC.
  • !
    NSEC3 with extra iterations or salt
    NSEC3 uses 10 iterations and a 8-byte salt. RFC 9276 recommends 0 iterations and no salt: extra iterations cost resolvers CPU and add no real protection, and some validators treat high counts as insecure.
    #31

Records

info

20 records at the apex

Found

Read from
192.87.106.101:53
TypeValueTTL
SOAumcdns05.umcn.nl. netwerkbeheerict.radboudumc.nl. 2019146679 10800 1080 2419200 9003600
NSns1.surfnet.nl.3600
NSumcdns05.umcn.nl.3600
NSns1.zurich.surf.net.3600
A131.174.154.1183600
MX10 radboudumc-nl.h-v1.mx.microsoft.3600
TXT"google-site-verification=7XxBzRXUH50oNuPT3AZcu66y3P939YxYkr1ApX2mm3A"3600
TXT"apple-domain-verification=4sgQGInEH3lTIAxh"3600
TXT"HARICA-dJjXaj0FcUJ1pXvuzwK"3600
TXT"HARICA-HTQ35f1RudUceFRtZKC"3600
TXT"v=NTA7516-1;startdate=2026-07;enddate=2029-07;provider=zorgmail;ntamx=10" "relay.zorgmail.nl"3600
TXT"ZOOM_verify_R5dUgzwaTAeExIl3I5P-5w"3600
TXT"v=msv1 t=B665014D-2AB6-43C4-8601-AA055294751D"3600
TXT"apple-domain-verification=0j7xqC6Vd6WWElST"3600
TXT"brevo-code:3bef0835566607e38833013159127d38"3600
TXT"v=spf1 include:spf.protection.outlook.com ip4:131.174.160.96/28 ip4:131.174.165.0/24 ip4:131.174.244.11 include:spf1.radboudumc.nl -all"3600
TXT"adobe-idp-site-verification=8f2b7686c66af5ee6d5d323b408a8f222f6e438a9e7953d49276629161d2259b"3600
TXT"MS=ms79134284"3600
TXT"cisco-ci-domain-verification=5357d910ee2b223bb0866245fa2421e84ed7b69a283650757c4065e52719cb64"3600
TXT"MS=ms84886167"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 1h, MX 1h, NS 1h.
  • ✓ 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