Domain report: erasmusmc.nl

Registration

info

.nl country-code

Found

TLD: .nl (country-code)
ICANN policies apply: no

Lookup error: https://rdap.sidn.nl/domain/erasmusmc.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/erasmusmc.nl returned HTTP 429

#3

Delegation

info

dns1.erasmusmc.nl, ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.nl

Found

Parent zone: nl
Delegation from: ns1.dns.nl (194.0.28.53)
NS at the parent: dns1.erasmusmc.nl, ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.nl
NS in the zone: dns1.erasmusmc.nl, ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.nl

Nameserver	Addresses	Network (AS)	Glue
dns1.erasmusmc.nl	156.83.10.153	AS1103 SURFNET-NL - SURF B.V., NL	156.83.10.153
ns1.surfnet.nl	192.87.106.101 2001:610:1:800a:192:87:106:101	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	192.87.106.101 2001:610:1:800a:192:87:106:101
ns1.zurich.surf.net	195.176.255.9 2001:620:0:9::1103	AS559 Switch - SWITCH, CH AS559 Switch - SWITCH, CH	-
ns2.surfnet.nl	192.87.36.2 2001:610:3:200a:192:87:36:2	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	192.87.36.2 2001:610:3:200a:192:87:36:2
ns3.surfnet.nl	195.169.124.71 2001:610:0:800c:195:169:124:71	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	195.169.124.71 2001:610:0:800c:195:169:124:71

Checks

✓ 5 nameservers #6

Delegated to dns1.erasmusmc.nl, ns1.surfnet.nl, ns1.zurich.surf.net, ns2.surfnet.nl, ns3.surfnet.nl.
✓ 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: dns1.erasmusmc.nl.
✓ 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 5 IPv4 /24s and 4 IPv6 /48s.
✓ 2 autonomous systems #11

The nameservers are spread over: AS1103 (SURFNET-NL - SURF B.V., NL): 7 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: dns1.erasmusmc.nl.

#13

Nameservers

info

9 of 9 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
dns1.erasmusmc.nl 156.83.10.153	NOERROR, 12 ms, authoritative	no	yes / yes	refused	-
ns1.surfnet.nl 192.87.106.101	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns1.surfnet.nl 2001:610:1:800a:192:87:106:101	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns1.zurich.surf.net 195.176.255.9	NOERROR, 9 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surf.nl
ns1.zurich.surf.net 2001:620:0:9::1103	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surf.nl
ns2.surfnet.nl 192.87.36.2	NOERROR, 12 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns2.surfnet.nl 2001:610:3:200a:192:87:36:2	NOERROR, 12 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns3.surfnet.nl 195.169.124.71	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl
ns3.surfnet.nl 2001:610:0:800c:195:169:124:71	NOERROR, 10 ms, authoritative	no	yes / yes	refused	This is a SURFnet nameserver - dns-beheer@surfnet.nl

Checks

✓ All respond #14

All 9 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"; ns2.surfnet.nl: "This is a SURFnet nameserver - dns-beheer@surfnet.nl"; ns3.surfnet.nl: "This is a SURFnet nameserver - dns-beheer@surfnet.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 2026042881 · primary dns1.erasmusmc.nl

Found

Primary (MNAME): dns1.erasmusmc.nl
Contact (RNAME): hostmaster.erasmusmc.nl
Serial: 2026042881
Refresh / retry: 3600 s / 600 s
Expire: 1209600 s
Negative TTL: 3600 s

Serial per nameserver

Nameserver	Serial
dns1.erasmusmc.nl (156.83.10.153)	2026042881
ns1.surfnet.nl (192.87.106.101)	2026042881
ns1.surfnet.nl (2001:610:1:800a:192:87:106:101)	2026042881
ns1.zurich.surf.net (195.176.255.9)	2026042881
ns1.zurich.surf.net (2001:620:0:9::1103)	2026042881
ns2.surfnet.nl (192.87.36.2)	2026042881
ns2.surfnet.nl (2001:610:3:200a:192:87:36:2)	2026042881
ns3.surfnet.nl (195.169.124.71)	2026042881
ns3.surfnet.nl (2001:610:0:800c:195:169:124:71)	2026042881

Checks

✓ Serial 2026042881 everywhere #22

All nameservers serve the same version of the zone.
✓ Timers within recommendations #23

SOA refresh 1h, retry 10m, expire 14d, negative TTL 1h.
✓ Primary is a public nameserver #24

The primary nameserver dns1.erasmusmc.nl is one of the listed nameservers.
✓ Contact hostmaster@erasmusmc.nl #25

The SOA RNAME hostmaster.erasmusmc.nl means hostmaster@erasmusmc.nl.
✓ Date-based serial #26

The serial 2026042881 follows the YYYYMMDDnn convention (2026-04-28).

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC3
NSEC3: 0 iterations, 16-byte salt
Signatures valid until: 12 November 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
21273	ECDSAP256SHA256 (13)	SHA256 944F2F7FBC740DF8…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
21273	KSK (257)	ECDSAP256SHA256 (13)
60816	ZSK (256)	ECDSAP256SHA256 (13)
28341	ZSK (256)	ECDSAP256SHA256 (13)
43017	ZSK (256)	ECDSAP256SHA256 (13)
2172	ZSK (256)	ECDSAP256SHA256 (13)

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 21273 (SHA256).
✓ Modern algorithms #29

Key algorithms: ECDSAP256SHA256 (13).
✓ Signatures valid until 2026-11-12 #30

The earliest DNSKEY/SOA signature expires at 2026-11-12 01:28 UTC.
!

NSEC3 with extra iterations or salt

NSEC3 uses 0 iterations and a 16-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

pass

21 records at the apex

Found

Read from: 156.83.10.153:53

Type	Value	TTL
SOA	dns1.erasmusmc.nl. hostmaster.erasmusmc.nl. 2026042881 3600 600 1209600 3600	3600
NS	ns3.surfnet.nl.	300
NS	ns1.surfnet.nl.	300
NS	ns1.zurich.surf.net.	300
NS	ns2.surfnet.nl.	300
NS	dns1.erasmusmc.nl.	300
A	13.69.68.43	300
MX	10 erasmusmc-nl.k-v1.mx.microsoft.	300
TXT	"P7tCkGABr4Ccsk3MDk81JMVA/HSTIEMTT7O+UDNxJO0ZIwMqbHZrL8DDMNKGUHmVdeJMZFTRQR1jy1VlmE8CCQ=="	3600
TXT	"adobe-idp-site-verification=be19d0b6536173593de228a99ad183f3af22ff93de92055921ad375c246ce8e5"	3600
TXT	"samsung-domain-verification=6852a1f8-d462-4112-a3dc-054b93ca2571"	3600
TXT	"v=NTA7516-1;startdate=2024-01;enddate=2027-01;provider=zorgmail;ntamx=10 relay.zorgmail.nl"	3600
TXT	"HARICA-OeWGTxcW6V0FxwtZp1h"	3600
TXT	"MS=ms45201007"	3600
TXT	"ZOOM_verify__xGBs08SSte4FhVP_BkncQ"	3600
TXT	"google-site-verification=sQBqjiJo3oHbzmflHIr42HKiQre7_4s8usvpy3hIehU"	3600
TXT	"apple-domain-verification=w96sumUEmoF0LCYn"	3600
TXT	"v=spf1 ip4:156.83.10.0/24 ip4:194.158.15.2/25 include:spfext.erasmusmc.nl include:spfext2.erasmusmc.nl ip4:35.177.224.195 ip4:52.77.71.183 ip4:83.149.98.72 ip4:212.204.201.35" " include:spf.protection.outlook.com include:_spf.zorgmail.nl -all"	3600
CAA	0 issue "harica.gr"	3600
CAA	0 issuewild "letsencrypt.org"	3600
CAA	0 issuewild "harica.gr"	3600

Checks

✓ TTLs within range #32

TTLs: A 5m, MX 5m, NS 5m. The NS TTL at the parent is 1h and in the zone 5m; 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.
✓ CAA restricts issuance #35

Certificates may be issued by: harica.gr, letsencrypt.org.