olvg.nl

Checked 22 October 2026, 15:01 UTC · via 8.8.8.8
!Passed with warnings
24 passed 3 warnings 0 failed 6 info

Registration

info

.nl country-code

Found

TLD
.nl (country-code)
ICANN policies apply
no
Lookup error: https://rdap.sidn.nl/domain/olvg.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/olvg.nl returned HTTP 429
    #3

Delegation

warn

ns3.olvg.nl, ns4.olvg.nl

Found

Parent zone
nl
Delegation from
ns1.dns.nl (194.0.28.53)
NS at the parent
ns3.olvg.nl, ns4.olvg.nl
NS in the zone
ns3.olvg.nl, ns4.olvg.nl
NameserverAddressesNetwork (AS)Glue
ns3.olvg.nl194.13.75.163AS1126 VANCIS - IDDQD-AS, EU194.13.75.163
ns4.olvg.nl194.13.75.164AS1126 VANCIS - IDDQD-AS, EU194.13.75.164

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns3.olvg.nl, ns4.olvg.nl.
    #6
  • ✓ 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: ns3.olvg.nl, ns4.olvg.nl.
  • ✓ All names resolve #9
    Every nameserver name has an address and is not an alias.
  • !
    Nameservers in one network
    all IPv4 addresses are in 194.13.75.0/24. A single network failure takes all nameservers down; RFC 2182 recommends topologically separate networks (anycast setups are an exception).
    #10
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS1126 (VANCIS - IDDQD-AS, EU): 2 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
  • !
    No IPv6
    None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.
    #13

Nameservers

pass

2 of 2 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns3.olvg.nl 194.13.75.163NOERROR, 10 ms, authoritativenoyes / yesrefused-
ns4.olvg.nl 194.13.75.164NOERROR, 11 ms, authoritativenoyes / yesrefused-

Checks

  • ✓ All respond #14
    All 2 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 2019165806 · primary ns3.olvg.nl

Found

Primary (MNAME)
ns3.olvg.nl
Contact (RNAME)
netwerkbeheer.olvg.nl
Serial
2019165806
Refresh / retry
10800 s / 1080 s
Expire
2419200 s
Negative TTL
900 s

Serial per nameserver

NameserverSerial
ns3.olvg.nl (194.13.75.163)2019165806
ns4.olvg.nl (194.13.75.164)2019165806

Checks

  • ✓ Serial 2019165806 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 18m, expire 28d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns3.olvg.nl is one of the listed nameservers.
  • ✓ Contact netwerkbeheer@olvg.nl #25
    The SOA RNAME netwerkbeheer.olvg.nl means netwerkbeheer@olvg.nl.
  • ✓ Timestamp serial #26
    The serial 2019165806 is a Unix timestamp (2033-12-25 23:23 UTC).

DNSSEC

warn

Signed, DS published at parent

Found

Validated by resolver
yes
Denial of existence
NSEC3
NSEC3
10 iterations, 13-byte salt
Signatures valid until
26 October 2026

DS at the parent

Key tagAlgorithmDigestMatches a key
32450RSASHA256 (8)SHA256 C6F85E6ECEF1B546…yes
892RSASHA256 (8)SHA256 B65251B8FE43735A…yes
11944RSASHA256 (8)SHA256 C427E064DCAA04F0…NO

DNSKEY in the zone

Key tagRoleAlgorithm
62769ZSK (256)RSASHA256 (8)
32450KSK (257)RSASHA256 (8)
892KSK (257)RSASHA256 (8)
59985ZSK (256)RSASHA256 (8)

Checks

  • ✓ Signed and validated #27
    The zone is signed, the parent publishes a DS record, and the resolver validates the answers.
  • i
    Unused DS records
    These DS records match no key in the zone: key tag 11944 (SHA256). That is normal during a key rollover; otherwise remove them.
    #28
  • ✓ 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 2026-10-22 10:49 UTC and expires at 2026-10-26 11:30 UTC.
  • !
    NSEC3 with extra iterations or salt
    NSEC3 uses 10 iterations and a 13-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

16 records at the apex

Found

Read from
194.13.75.163:53
TypeValueTTL
SOAns3.olvg.nl. netwerkbeheer.olvg.nl. 2019165806 10800 1080 2419200 90028800
NSns4.olvg.nl.28800
NSns3.olvg.nl.28800
A20.105.224.4228800
MX10 mx2.olvg.nl.86400
MX10 mx1.olvg.nl.86400
TXT"cisco-ci-domain-verification=6cbdc1828c413d7c1fa197a2e7aa37a87126d9ac109d5f877dd85680127b65ec"3600
TXT"v=spf1 a include:_spf.zorgmail.nl include:spf.protection.outlook.com ip4:194.13.72.0/21 ip4:85.90.80.192/27 ip4:20.105.224.42/32 mx:olvg.nl ~all"3600
TXT"MS=ms96839542"3600
TXT"MS=msJjK-u11-My5" "MS=ms94805469"3600
TXT"apple-domain-verification=g4pcIiMF6aNkS3A4"3600
TXT"citrix.mobile.ads.otp=turwikuajs74i9t7moagen"3600
TXT"google-site-verification=RdEi3fLDAJq3d8NM6HUQJF6FEWEL1bOrjLugoWogyTc"3600
TXT"google-site-verification=x7KLFmDzsOREtP39-1sDVdGebT8mg6svaTbiF2ryi_8"3600
CAA0 issue "letsencrypt.org"28800
CAA0 issue "sectigo.com"28800

Checks

  • ✓ TTLs within range #32
    TTLs: A 8h, MX 1d, 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: letsencrypt.org, sectigo.com.