ikstopnu.nl

Checked 22 October 2026, 13:52 UTC · via 8.8.8.8
!Passed with warnings
27 passed 5 warnings 0 failed 1 info

SPF

pass

SPF record published

Found

Record
v=spf1 include:spf-breaks-email.bit.nl ~all
DNS lookups
1 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 1 of 10 DNS lookups #2
    SPF record needs 1 DNS lookups (limit is 10).
  • ✓ Ends with ~all #3
    SPF record properly uses ~all to restrict unauthorized senders.
  • ✓ Record published #6
    SPF record exists for this domain.
  • ✓ Single record #16
    Exactly one SPF record is published.
  • ✓ Valid syntax #25
    All SPF mechanisms and modifiers are valid.
  • ✓ No void lookups #26
    All include/redirect targets exist.
  • ✓ No overly broad IP ranges #27
    All ip4/ip6 ranges are narrow enough.

DMARC

warn

p=quarantine (_dmarc.ikstopnu.nl)

Found

Record
v=DMARC1; p=quarantine; fo=1; rua=mailto:dmarc@trimbos.nl
Found at
_dmarc.ikstopnu.nl
External report address
mailto:dmarc@trimbos.nl (not authorized)
TagValueMeaning
vDMARC1Version
pquarantinePolicy
ruamailto:dmarc@trimbos.nlAggregate report addresses
fo1Failure reporting options

Checks

  • !
    Policy: quarantine
    DMARC policy is set to 'quarantine'. Consider upgrading to 'reject' for stronger protection once you've verified legitimate emails are passing authentication.
    #4
  • ✓ Record published #5
    DMARC record exists for this domain.
  • ✓ Valid syntax #17
    DMARC record syntax is valid.
  • ✓ Applies to 100% of mail #18
    DMARC policy applies to all failing mail.
  • ✓ Aggregate reports enabled #19
    Aggregate reports are sent to: mailto:dmarc@trimbos.nl
  • ✓ Subdomain policy: quarantine #20
    Subdomains are covered by policy 'quarantine'.
  • !
    Report address not authorized
    These report addresses are in another domain that has not agreed to receive your reports, so receivers will not send them: mailto:dmarc@trimbos.nl (needs ikstopnu.nl._report._dmarc.trimbos.nl). Ask the report provider to publish the record, or check the address.
    #29

DKIM

warn

Selectors: s1, s2

Found

Selectors
s1, s2
_domainkey
NOERROR
SelectorKeyFlags
s1RSA 2048 bits
s2RSA 1024 bits

Checks

  • ✓ Keys found: s1, s2 #7
    DKIM keys found for this domain with selectors: s1, s2
  • !
    1024-bit DKIM key
    1024-bit RSA keys are the minimum and are considered weak today: s2 (1024 bits). Rotate to a 2048-bit key.
    #23
  • ✓ No problematic flags #24
    No keys in test mode, revoked, or limited to SHA-1.

DNSSEC

pass

Signed, DS published at parent

Found

DNSKEY records
Yes (2)
DS at parent
Yes
Algorithms
ECDSAP256SHA256 (13)
Key tags
34505, 2371
Signatures valid until
18 December 2026, 10:57 UTC

Checks

  • ✓ Signed, DS published at parent #8
    DNSSEC is enabled for this domain (DNSKEY and DS present), providing additional security for DNS lookups.
  • ✓ Signatures valid until 2026-12-18 #21
    DNSKEY signatures are valid until 2026-12-18T10:57:59Z.

MX

pass

3 mail servers

Found

PriorityHostRecordsReverse DNS
10mx1.bit.nlA 213.136.12.237 AAAA 2001:7b8:3:5::25:5mx.lb.network.bit.nl ✓ mx.bit.nl ✓
20mx2.bit.nlA 213.136.12.237 AAAA 2001:7b8:3:5::25:5mx.lb.network.bit.nl ✓ mx.bit.nl ✓
30mx3.bit.orgA 213.136.12.235 AAAA 2001:7b8:3:5::25:8mx3.lb.network.bit.nl ✓ mx3.bit.org ✓

Checks

  • ✓ 3 MX records #9
    Found 3 MX records for this domain.
  • ✓ All hosts resolve #10
    All MX records resolve to valid IP addresses.
  • ✓ All hosts have IPv6 #11
    All MX records resolve to IPv6 addresses.
  • ✓ Redundant MX hosts #12
    Found 3 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 3 MX records, which is within the recommended range (1-5).
  • ✓ No localhost targets #14
    No MX records pointing to localhost found.
  • ✓ No private IP addresses #15
    No MX records resolving to private IP addresses found.
  • ✓ No CNAME targets #22
    No MX records point to a CNAME.
  • ✓ Reverse DNS confirmed #30
    All 6 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 3 of 3 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
mx1.bit.nl3 0 1 9a2e6c42e329ca46… 3 0 1 7af199fd9f1f984d… 3 1 1 754131f10c5997a6… 3 1 1 1505554503c35fe7…Yes
mx2.bit.nl3 0 1 7af199fd9f1f984d… 3 0 1 9a2e6c42e329ca46… 3 1 1 754131f10c5997a6… 3 1 1 1505554503c35fe7…Yes
mx3.bit.org2 1 1 9d637b3d27a9e570… 2 1 1 2e8307068b6db620… 2 1 1 6ebcefb4210b0886… 2 1 1 51aaa87d984b559a… 2 1 1 a698a20824be04e4… 2 1 1 b3fb5d00e994cddf…Yes

Checks

  • !
    Not configured
    MTA-STS is not configured, so other mail servers fall back to unencrypted delivery when TLS fails or is stripped by an attacker. Publish a _mta-sts TXT record and a policy at https://mta-sts.<domain>/.well-known/mta-sts.txt.
    #32
  • !
    Not configured
    MTA-STS or DANE is used without TLS-RPT, so you get no reports when senders fail to deliver because of TLS problems. Publish _smtp._tls TXT "v=TLSRPTv1; rua=mailto:...".
    #35
  • ✓ DANE on all MX hosts #36
    All 3 MX hosts publish DNSSEC-validated TLSA records.

BIMI

info

No BIMI record

Checks

  • i
    Not configured
    BIMI shows your logo next to your mail in supporting mail clients. It requires DMARC enforcement.
    #38