Domain report: cbs.nl

Registration

info

.nl country-code

Found

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

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

#3

Delegation

pass

cbs01.dns.internl.net, dnsa3.cbs.nl, dnsa4.cbs.nl

Found

Parent zone: nl
Delegation from: ns1.dns.nl (194.0.28.53)
NS at the parent: cbs01.dns.internl.net, dnsa3.cbs.nl, dnsa4.cbs.nl
NS in the zone: cbs01.dns.internl.net, dnsa3.cbs.nl, dnsa4.cbs.nl

Nameserver	Addresses	Network (AS)	Glue
cbs01.dns.internl.net	77.95.250.75 2a00:1478:40:2::11:1	AS43190 GL-IX-AS - Totaalnet Internet Works B.V., NL AS43190 GL-IX-AS - Totaalnet Internet Works B.V., NL	-
dnsa3.cbs.nl	87.213.43.202 2001:67c:14b0:1805::15	AS13127 Odido - Odido Netherlands B.V., NL AS13127 Odido - Odido Netherlands B.V., NL	87.213.43.202 2001:67c:14b0:1805::15
dnsa4.cbs.nl	87.213.43.203 2001:67c:14b0:1805::16	AS13127 Odido - Odido Netherlands B.V., NL AS13127 Odido - Odido Netherlands B.V., NL	87.213.43.203 2001:67c:14b0:1805::16

Checks

✓ 3 nameservers #6

Delegated to cbs01.dns.internl.net, dnsa3.cbs.nl, dnsa4.cbs.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: dnsa3.cbs.nl, dnsa4.cbs.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 2 IPv4 /24s and 2 IPv6 /48s.
✓ 2 autonomous systems #11

The nameservers are spread over: AS13127 (Odido - Odido Netherlands B.V., NL): 4 addresses; AS43190 (GL-IX-AS - Totaalnet Internet Works B.V., NL): 2 addresses.
✓ Nameserver names under 2 TLDs #12

Nameserver names use the TLDs .net, .nl.
✓ All reachable over IPv6 #13

Every nameserver has an IPv6 address.

Nameservers

pass

6 of 6 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
cbs01.dns.internl.net 77.95.250.75	NOERROR, 11 ms, authoritative	no	yes / yes	refused	-
cbs01.dns.internl.net 2a00:1478:40:2::11:1	NOERROR, 11 ms, authoritative	no	yes / yes	refused	-
dnsa3.cbs.nl 87.213.43.202	NOERROR, 17 ms, authoritative	no	yes / yes	refused	-
dnsa3.cbs.nl 2001:67c:14b0:1805::15	NOERROR, 17 ms, authoritative	no	yes / yes	refused	-
dnsa4.cbs.nl 87.213.43.203	NOERROR, 17 ms, authoritative	no	yes / yes	refused	-
dnsa4.cbs.nl 2001:67c:14b0:1805::16	NOERROR, 17 ms, authoritative	no	yes / yes	refused	-

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.
✓ 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

warn

serial 2017043727 · primary dnsa4.cbs.nl

Found

Primary (MNAME): dnsa4.cbs.nl
Contact (RNAME): postmaster.cbs.nl
Serial: 2017043727
Refresh / retry: 900 s / 600 s
Expire: 43200 s
Negative TTL: 86400 s

Serial per nameserver

Nameserver	Serial
cbs01.dns.internl.net (77.95.250.75)	2017043727
cbs01.dns.internl.net (2a00:1478:40:2::11:1)	2017043727
dnsa3.cbs.nl (87.213.43.202)	2017043727
dnsa3.cbs.nl (2001:67c:14b0:1805::15)	2017043727
dnsa4.cbs.nl (87.213.43.203)	2017043727
dnsa4.cbs.nl (2001:67c:14b0:1805::16)	2017043727

Checks

✓ Serial 2017043727 everywhere #22

All nameservers serve the same version of the zone.
!

Unusual SOA timers

refresh 15m is outside 20m–1d; expire 12h is shorter than 7d; secondaries stop answering too soon when the primary is down. Current values: refresh 15m, retry 10m, expire 12h, negative TTL 1d.

#23
✓ Primary is a public nameserver #24

The primary nameserver dnsa4.cbs.nl is one of the listed nameservers.
✓ Contact postmaster@cbs.nl #25

The SOA RNAME postmaster.cbs.nl means postmaster@cbs.nl.
✓ Timestamp serial #26

The serial 2017043727 is a Unix timestamp (2033-12-01 09:55 UTC).

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC3
NSEC3: 0 iterations, 0-byte salt
Signatures valid until: 24 October 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
21049	RSASHA256 (8)	SHA256 BA1B1298AE649653…	yes
30340	RSASHA256 (8)	SHA256 FF4FA56DAD1145EA…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
27543	ZSK (256)	RSASHA256 (8)
41043	ZSK (256)	RSASHA256 (8)
21049	KSK (257)	RSASHA256 (8)
30340	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 21049 (SHA256), key tag 30340 (SHA256).
✓ Modern algorithms #29

Key algorithms: RSASHA256 (8).
!

Signatures expire soon

The earliest signature expires at 2026-10-24 14:47 UTC (in 66h0m0s). Check that automatic re-signing works.

#30
✓ NSEC3 as recommended #31

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

Records

pass

11 records at the apex

Found

Read from: 77.95.250.75:53

Type	Value	TTL
SOA	dnsa4.cbs.nl. postmaster.cbs.nl. 2017043727 900 600 43200 86400	86400
NS	dnsa4.cbs.nl.	86400
NS	dnsa3.cbs.nl.	86400
NS	cbs01.dns.internl.net.	86400
A	132.164.123.249	7200
AAAA	2603:1020:203:14::2c9	7200
MX	10 mailrelayh4.cbs.nl.	86400
MX	10 mailrelayh3.cbs.nl.	86400
TXT	"v=spf1 mx ip4:51.105.176.79 ip4:50.85.155.139 ip4:87.213.43.205 include:spf.afas.online include:imedia.nl include:spf.protection.outlook.com -all"	86400
CAA	0 issue "letsencrypt.org"	86400
CAA	0 issue "digicert.com"	86400

Checks

✓ TTLs within range #32

TTLs: A 2h, AAAA 2h, MX 1d, 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.
✓ CAA restricts issuance #35

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