Domain report: xs4all.nl

Registration

info

.nl country-code

Found

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

Lookup error: https://rdap.sidn.nl/domain/xs4all.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/xs4all.nl returned HTTP 429

#3

Delegation

info

ns1.kpn.net, ns11.kpn.net

Found

Parent zone: nl
Delegation from: ns1.dns.nl (194.0.28.53)
NS at the parent: ns1.kpn.net, ns11.kpn.net
NS in the zone: ns1.kpn.net, ns11.kpn.net

Nameserver	Addresses	Network (AS)	Glue
ns1.kpn.net	194.151.228.10 2a02:a47f:ac:1::153	AS1136 KPN - KPN B.V., NL AS1136 KPN - KPN B.V., NL	-
ns11.kpn.net	213.75.63.33 2a02:a47f:ac:1::1153	AS1136 KPN - KPN B.V., NL AS1136 KPN - KPN B.V., NL	-

Checks

i

2 nameservers

Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns1.kpn.net, ns11.kpn.net.

#6
✓ 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.
i

One address family in one network

all IPv6 addresses are in 2a02:a47f:ac::/48, while the other address family is spread over several networks.

#10
i

All nameservers in one AS

All nameserver addresses are announced by one network operator (AS1136 (KPN - KPN B.V., NL): 4 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 .net

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

pass

4 of 4 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
ns1.kpn.net 194.151.228.10	NOERROR, 10 ms, authoritative	no	yes / yes	refused	-
ns1.kpn.net 2a02:a47f:ac:1::153	NOERROR, 11 ms, authoritative	no	yes / yes	refused	-
ns11.kpn.net 213.75.63.33	NOERROR, 10 ms, authoritative	no	yes / yes	refused	-
ns11.kpn.net 2a02:a47f:ac:1::1153	NOERROR, 10 ms, authoritative	no	yes / yes	refused	-

Checks

✓ All respond #14

All 4 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.
✓ 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

pass

serial 2026101501 · primary ns1.kpn.net

Found

Primary (MNAME): ns1.kpn.net
Contact (RNAME): zonemaster.kpn.com
Serial: 2026101501
Refresh / retry: 10800 s / 3600 s
Expire: 604800 s
Negative TTL: 3600 s

Serial per nameserver

Nameserver	Serial
ns1.kpn.net (194.151.228.10)	2026101501
ns1.kpn.net (2a02:a47f:ac:1::153)	2026101501
ns11.kpn.net (213.75.63.33)	2026101501
ns11.kpn.net (2a02:a47f:ac:1::1153)	2026101501

Checks

✓ Serial 2026101501 everywhere #22

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

SOA refresh 3h, retry 1h, expire 7d, negative TTL 1h.
✓ Primary is a public nameserver #24

The primary nameserver ns1.kpn.net is one of the listed nameservers.
✓ Contact zonemaster@kpn.com #25

The SOA RNAME zonemaster.kpn.com means zonemaster@kpn.com.
✓ Date-based serial #26

The serial 2026101501 follows the YYYYMMDDnn convention (2026-10-15).

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: 29 October 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
47437	ECDSAP256SHA256 (13)	SHA256 3BA6C597A00690FF…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
47437	KSK (257)	ECDSAP256SHA256 (13)
19327	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 47437 (SHA256).
✓ Modern algorithms #29

Key algorithms: ECDSAP256SHA256 (13).
✓ Signatures valid until 2026-10-29 #30

The earliest DNSKEY/SOA signature expires at 2026-10-29 00:00 UTC.
✓ NSEC3 as recommended #31

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

Records

warn

18 records at the apex

Found

Read from: 194.151.228.10:53

Type	Value	TTL
SOA	ns1.kpn.net. zonemaster.kpn.com. 2026101501 10800 3600 604800 3600	3600
NS	ns11.kpn.net.	3600
NS	ns1.kpn.net.	3600
A	99.83.136.155	60
A	75.2.72.204	60
AAAA	2600:9000:a504:9080:40c0:d138:ca59:2e3d	3600
AAAA	2600:9000:a400:dede:1a1c:a23f:9ae6:7bbc	3600
MX	10 mx.kpnmail.nl.	60
TXT	"v=spf1 include:spf.ews.kpnxchange.com ~all"	3600
TXT	"MS=B895DD98732F0DADE7D04A1E53DF0DECBFEF770F"	3600
TXT	"google-site-verification=ixk8ILXv-df5AQBAbfJfXpu9EQUFYoHZwjAvpcG5tBE"	3600
TXT	"google-site-verification=qHhbnr_ViPAAN13v4NQGHDYCfXwM__O6XS9NJFL1IRI"	3600
CAA	0 issue "letsencrypt.org"	3600
CAA	0 issuewild "sectigo.com"	3600
CAA	0 issuewild "letsencrypt.org"	3600
CAA	0 issue "amazonaws.com"	3600
CAA	0 issue "sectigo.com"	3600
CAA	0 issue "comodoca.com"	3600

Checks

!

Very low TTLs

These records have a TTL below 5m, causing extra queries and slower lookups: A (1m), MX (1m). Low TTLs are useful just before a planned change.

#32
✓ 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, sectigo.com, amazonaws.com, comodoca.com.