Domain report: snn.nl

Registration

info

.nl country-code

Found

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

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

#3

Delegation

info

ns1.duocast.net, ns2.duocast.net

Found

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

Nameserver	Addresses	Network (AS)	Glue
ns1.duocast.net	83.137.146.53 2a01:1b0:4418::53	AS31477 DUOCAST-AS - Duocast B.V., NL AS31477 DUOCAST-AS - Duocast B.V., NL	-
ns2.duocast.net	91.209.7.53 2a01:1b1:4418::53	AS39292 DUOCASTBACKUP-AS - Duocast B.V., NL AS39292 DUOCASTBACKUP-AS - Duocast B.V., NL	-

Checks

i

2 nameservers

Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns1.duocast.net, ns2.duocast.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.
✓ Nameservers in different networks #10

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

The nameservers are spread over: AS31477 (DUOCAST-AS - Duocast B.V., NL): 2 addresses; AS39292 (DUOCASTBACKUP-AS - Duocast B.V., NL): 2 addresses.
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

fail

4 of 4 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
ns1.duocast.net 83.137.146.53	NOERROR, 13 ms, authoritative	no	yes / yes	refused	-
ns1.duocast.net 2a01:1b0:4418::53	NOERROR, 13 ms, authoritative	no	yes / yes	refused	-
ns2.duocast.net 91.209.7.53	NOERROR, 12 ms, authoritative	no	yes / yes	refused	-
ns2.duocast.net 2a01:1b1:4418::53	NOERROR, 12 ms, authoritative	no	no / 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.
✗

No DNS over TCP

DNS over TCP is required (RFC 7766); without it, large answers such as DNSSEC responses fail. Not answering over TCP: ns2.duocast.net (2a01:1b1:4418::53): read tcp [2a01:4f8:1c1c:eebf::1]:34710->[2a01:1b1:4418::53]:53: read: connection reset by peer.

#19
✓ EDNS supported #20

All nameservers support EDNS(0).
✓ Public addresses #21

All nameserver addresses are publicly routable.

SOA

pass

serial 2026102001 · primary ns1.duocast.net

Found

Primary (MNAME): ns1.duocast.net
Contact (RNAME): hostmaster.duocast.net
Serial: 2026102001
Refresh / retry: 10800 s / 3600 s
Expire: 604800 s
Negative TTL: 86400 s

Serial per nameserver

Nameserver	Serial
ns1.duocast.net (83.137.146.53)	2026102001
ns1.duocast.net (2a01:1b0:4418::53)	2026102001
ns2.duocast.net (91.209.7.53)	2026102001
ns2.duocast.net (2a01:1b1:4418::53)	2026102001

Checks

✓ Serial 2026102001 everywhere #22

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

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

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

The SOA RNAME hostmaster.duocast.net means hostmaster@duocast.net.
✓ Date-based serial #26

The serial 2026102001 follows the YYYYMMDDnn convention (2026-10-20).

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC3
NSEC3: 1 iterations, 2-byte salt
Signatures valid until: 5 November 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
56671	ECDSAP256SHA256 (13)	SHA256 813428A530FE6EAC…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
56671	KSK (257)	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 56671 (SHA256).
✓ Modern algorithms #29

Key algorithms: ECDSAP256SHA256 (13).
✓ Signatures valid until 2026-11-05 #30

The earliest DNSKEY/SOA signature expires at 2026-11-05 00:00 UTC.
!

NSEC3 with extra iterations or salt

NSEC3 uses 1 iteration and a 2-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

11 records at the apex

Found

Read from: 83.137.146.53:53

Type	Value	TTL
SOA	ns1.duocast.net. hostmaster.duocast.net. 2026102001 10800 3600 604800 86400	86400
NS	ns1.duocast.net.	86400
NS	ns2.duocast.net.	86400
A	185.108.112.24	600
AAAA	2a01:7c8:bb03:ae:5054:ff:fe49:e04c	3600
MX	0 snn-nl.o-v1.mx.microsoft.	3600
TXT	"d365mktkey=nR6shpJFDjvp7YzuGK2tALGYynPJVS08YZNMhgeXIqkx"	3600
TXT	"MS=ms31247182"	3600
TXT	"QuoVadis=202ff08b-744c-447e-b13a-a4c8fad5712c"	3600
TXT	"v=spf1 ip4:193.9.23.103 include:customers.clickdimensions.com include:spf.EU.exclaimer.net include:spf.protection.outlook.com include:_spf.eu.messagegears.net a:mail.adix.nl a:snn.eu include:spf.afas.online include:_spf.transip.email a:snn-mail.duocast.ne" "t -all"	3600
TXT	"google-site-verification=3GkuBAxlj3YjYscKZV9QJkiZvgNU5oB5YmS8qNmlVbk"	3600

Checks

✓ TTLs within range #32

TTLs: A 10m, AAAA 1h, MX 1h, NS 1d. The NS TTL at the parent is 1h and in the zone 1d; 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.
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