Domain report: hogeschoolrotterdam.nl

Registration

info

.nl country-code

Found

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

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

#3

Delegation

fail

dns-01.hro.nl, dns-02.hro.nl, dns-03.hro.nl

Found

Parent zone: nl
Delegation from: ns1.dns.nl (194.0.28.53)
NS at the parent: dns-01.hro.nl, dns-02.hro.nl, dns-03.hro.nl
NS in the zone: dns-01.hro.nl, dns-02.hro.nl, tasarov.hro.nl

Nameserver	Addresses	Network (AS)	Glue
dns-01.hro.nl	145.24.1.204	AS1103 SURFNET-NL - SURF B.V., NL	145.24.1.204
dns-02.hro.nl	145.24.159.204	AS1103 SURFNET-NL - SURF B.V., NL	145.24.159.204
dns-03.hro.nl (parent only)	(does not resolve)		-
tasarov.hro.nl (zone only)	46.19.32.138 2a02:2770:3:0:21a:4aff:fece:8edf	AS196752 TILAA - Tilaa B.V., NL AS196752 TILAA - Tilaa B.V., NL	-

Checks

✓ 3 nameservers #6

Delegated to dns-01.hro.nl, dns-02.hro.nl, dns-03.hro.nl.
!

NS sets differ

The nameservers at the parent and in the zone should be the same. Only at the parent: dns-03.hro.nl; only in the zone: tasarov.hro.nl. dns-01.hro.nl, dns-02.hro.nl report NS dns-01.hro.nl dns-02.hro.nl tasarov.hro.nl.

#7
✓ No glue needed #8

All nameservers are outside the zone, so no glue records are needed.
✗

Nameserver names don't resolve

These nameservers have no A or AAAA record, so they can't be reached (lame delegation): dns-03.hro.nl.

#9
✓ Nameservers in different networks #10

The nameservers are spread over 3 IPv4 /24s and 1 IPv6 /48.
✓ 2 autonomous systems #11

The nameservers are spread over: AS1103 (SURFNET-NL - SURF B.V., NL): 2 addresses; AS196752 (TILAA - Tilaa B.V., NL): 2 addresses.
i

All nameserver names under .nl

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
i

Partly IPv6

These nameservers have no IPv6 address: dns-01.hro.nl, dns-02.hro.nl.

#13

Nameservers

fail

2 of 4 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
dns-01.hro.nl 145.24.1.204	NOERROR, 13 ms, authoritative	no	yes / yes	refused	-
dns-02.hro.nl 145.24.159.204	NOERROR, 13 ms, authoritative	no	yes / yes	refused	-
tasarov.hro.nl 46.19.32.138	no response	no	no / no	-	-
tasarov.hro.nl 2a02:2770:3:0:21a:4aff:fece:8edf	no response	no	no / no	-	-

Checks

✗

Nameservers not responding

These addresses did not answer, so resolvers waste time on timeouts: tasarov.hro.nl (46.19.32.138): read udp 46.225.38.91:34269->46.19.32.138:53: read: connection refused; tasarov.hro.nl (2a02:2770:3:0:21a:4aff:fece:8edf): read udp [2a01:4f8:1c1c:eebf::1]:52009->[2a02:2770:3:0:21a:4aff:fece:8edf]:53: read: connection refused.

#14
✓ All authoritative #15

Every responding nameserver answers authoritatively for the zone.
✓ No recursion #16

The nameservers do not answer recursive queries for other domains.
✓ No version disclosed #17

The nameservers don't reveal their software version.
✓ 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

info

serial 2026101286 · primary ib-gm-mgmt.hro.nl

Found

Primary (MNAME): ib-gm-mgmt.hro.nl
Contact (RNAME): hostmaster.hro.nl
Serial: 2026101286
Refresh / retry: 10800 s / 3600 s
Expire: 2419200 s
Negative TTL: 900 s

Serial per nameserver

Nameserver	Serial
dns-01.hro.nl (145.24.1.204)	2026101286
dns-02.hro.nl (145.24.159.204)	2026101286

Checks

✓ Serial 2026101286 everywhere #22

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

SOA refresh 3h, retry 1h, expire 28d, negative TTL 15m.
i

Hidden master

The primary nameserver ib-gm-mgmt.hro.nl is not listed as a nameserver: a hidden master that only feeds the public secondaries. That is a common setup; make sure it is not reachable for zone transfers from outside.

#24
✓ Contact hostmaster@hro.nl #25

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

The serial 2026101286 follows the YYYYMMDDnn convention (2026-10-12).

DNSSEC

pass

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC3
NSEC3: 0 iterations, 0-byte salt
Signatures valid until: 25 October 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
49684	RSASHA256 (8)	SHA256 E49F325D349E34D1…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
49684	KSK (257)	RSASHA256 (8)
52120	ZSK (256)	RSASHA256 (8)
55608	ZSK (256)	RSASHA256 (8)

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 49684 (SHA256).
✓ Modern algorithms #29

Key algorithms: RSASHA256 (8).
✓ Short-lived signatures (online signing) #30

Signatures are valid for 97h0m0s and created on demand; the current one was made at 2026-10-21 04:14 UTC and expires at 2026-10-25 04:45 UTC.
✓ NSEC3 as recommended #31

The zone uses NSEC3 with 0 iterations and no salt (RFC 9276).

Records

pass

16 records at the apex

Found

Read from: 145.24.1.204:53

Type	Value	TTL
SOA	ib-gm-mgmt.hro.nl. hostmaster.hro.nl. 2026101286 10800 3600 2419200 900	28800
NS	dns-02.hro.nl.	28800
NS	tasarov.hro.nl.	28800
NS	dns-01.hro.nl.	28800
A	145.24.159.123	3600
MX	100 suffix06.hro.nl.	3600
MX	100 suffix05.hro.nl.	3600
TXT	"d365mktkey=6upex25kzy9vupbr9755z6e54"	3600
TXT	"ZOOM_verify_WNI5kNxHQcK1w9XHEuGgRw"	3600
TXT	"HARICA-NHatdzr7t5dichAdk8S"	3600
TXT	"v=spf1 redirect=hr.nl"	3600
TXT	"facebook-domain-verification=tmzl06etz6riuhfra01n216qs089ku"	3600
TXT	"d365mktkey=gtgUA4Kt4x6B5sqBy4YQd6xlINE2wtYpL6xK1PIA0a4x"	3600
CAA	0 issue "sectigo.com"	3600
CAA	0 issue "harica.gr"	3600
CAA	0 iodef "mailto:ca-reports@hr.nl"	3600

Checks

✓ TTLs within range #32

TTLs: A 1h, MX 1h, NS 8h. The NS TTL at the parent is 1h and in the zone 8h; 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: sectigo.com, harica.gr.