Domain report: zeeuwseankers.nl

Registration

info

.nl country-code

Found

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

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

#3

Delegation

info

ns1.zebi.nl, ns2.surfnet.nl, ns2.zebi.nl

Found

Parent zone: nl
Delegation from: ns1.dns.nl (194.0.28.53)
NS at the parent: ns1.zebi.nl, ns2.surfnet.nl, ns2.zebi.nl
NS in the zone: ns1.zebi.nl, ns2.surfnet.nl, ns2.zebi.nl

Nameserver	Addresses	Network (AS)	Glue
ns1.zebi.nl	192.87.78.208 2001:610:2f0:7::208	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	192.87.78.208 2001:610:2f0:7::208
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
ns2.zebi.nl	192.87.78.209 2001:610:2f0:7::209	AS1103 SURFNET-NL - SURF B.V., NL AS1103 SURFNET-NL - SURF B.V., NL	192.87.78.209 2001:610:2f0:7::209

Checks

✓ 3 nameservers #6

Delegated to ns1.zebi.nl, ns2.surfnet.nl, ns2.zebi.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 2 IPv4 /24s and 2 IPv6 /48s.
i

All nameservers in one AS

All nameserver addresses are announced by one network operator (AS1103 (SURFNET-NL - SURF B.V., NL): 6 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 .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
✓ All reachable over IPv6 #13

Every nameserver has an IPv6 address.

Nameservers

warn

6 of 6 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
ns1.zebi.nl 192.87.78.208	NOERROR, 14 ms, authoritative	no	yes / yes	refused	9.18.49-1~deb12u2-Debian
ns1.zebi.nl 2001:610:2f0:7::208	NOERROR, 14 ms, authoritative	no	yes / yes	refused	9.18.49-1~deb12u2-Debian
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
ns2.zebi.nl 192.87.78.209	NOERROR, 14 ms, authoritative	no	yes / yes	refused	9.18.49-1~deb12u2-Debian
ns2.zebi.nl 2001:610:2f0:7::209	NOERROR, 14 ms, authoritative	no	yes / yes	refused	9.18.49-1~deb12u2-Debian

Checks

✓ All respond #14

All 6 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.zebi.nl: "9.18.49-1~deb12u2-Debian"; ns2.zebi.nl: "9.18.49-1~deb12u2-Debian". 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

warn

serial 1081 · primary ns1.zebi.nl

Found

Primary (MNAME): ns1.zebi.nl
Contact (RNAME): hostmaster.zebi.nl
Serial: 1081
Refresh / retry: 900 s / 600 s
Expire: 1209600 s
Negative TTL: 3600 s

Serial per nameserver

Nameserver	Serial
ns1.zebi.nl (192.87.78.208)	1081
ns1.zebi.nl (2001:610:2f0:7::208)	1081
ns2.surfnet.nl (192.87.36.2)	1081
ns2.surfnet.nl (2001:610:3:200a:192:87:36:2)	1081
ns2.zebi.nl (192.87.78.209)	1081
ns2.zebi.nl (2001:610:2f0:7::209)	1081

Checks

✓ Serial 1081 everywhere #22

All nameservers serve the same version of the zone.
!

Unusual SOA timers

refresh 15m is outside 20m–1d. Current values: refresh 15m, retry 10m, expire 14d, negative TTL 1h.

#23
✓ Primary is a public nameserver #24

The primary nameserver ns1.zebi.nl is one of the listed nameservers.
✓ Contact hostmaster@zebi.nl #25

The SOA RNAME hostmaster.zebi.nl means hostmaster@zebi.nl.
✓ Counter serial #26

The serial 1081 is a plain counter.

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC3
NSEC3: 50 iterations, 8-byte salt
Signatures valid until: 29 October 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
7525	RSASHA256 (8)	SHA256 F2FA8CB908B32B10…	yes
7444	RSASHA256 (8)	SHA256 D88F84CADB0C162C…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
9947	KSK (257)	RSASHA256 (8)
7525	KSK (257)	RSASHA256 (8)
37875	ZSK (256)	RSASHA256 (8)
16630	ZSK (256)	RSASHA256 (8)
7444	KSK (257)	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 7525 (SHA256), key tag 7444 (SHA256).
✓ Modern algorithms #29

Key algorithms: RSASHA256 (8).
!

Signatures expire soon

The earliest signature expires at 2026-10-29 03:59 UTC (in 155h0m0s). Check that automatic re-signing works.

#30
!

NSEC3 with extra iterations or salt

NSEC3 uses 50 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

pass

12 records at the apex

Found

Read from: 192.87.78.208:53

Type	Value	TTL
SOA	ns1.zebi.nl. hostmaster.zebi.nl. 1081 900 600 1209600 3600	3600
NS	ns1.zebi.nl.	3600
NS	ns2.surfnet.nl.	3600
NS	ns2.zebi.nl.	3600
A	185.173.21.203	3600
MX	10 mx.transip.email.	3600
TXT	"v=spf1 include:mailfilter.myrootnet.nl ~all"	3600
CAA	0 issue "letsencrypt.org"	3600
CAA	0 issue "digicert.com"	3600
CAA	0 issue "harica.gr"	3600
CAA	0 iodef "mailto:hostmaster@zebi.nl"	3600
CAA	0 issue "sectigo.com"	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.
✓ No wildcard #34

Names that don't exist return NXDOMAIN.
✓ CAA restricts issuance #35

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