Mail domain report: hostnet.nl

SPF

pass

SPF record published

Found

Record: v=spf1 include:spf.patchman.co include:mail.zendesk.com include:spf.protection.outlook.com include:_spf.g1i.one include:secure-mailgate.com ip4:91.184.8.0/24 ?ip4:216.40.35.246 ?ip4:216.40.35.247 ?ip4:216.40.35.248 ?ip4:85.17.215.68 ?ip4:85.17.215.85 ?ip4:78.137.101.38 ?ip4:78.137.101.36 ?ip4:78.137.101.37 ?ip4:213.125.243.75 ip4:37.128.151.38 ?ip4:37.128.151.39 ip4:205.201.128.0/20 ip4:198.2.128.0/18 ip4:148.105.8.0/21 ip4:194.146.184.134 ip4:194.146.184.135 ip4:91.184.19.0/24 ?ip4:91.184.0.0/19 -all
DNS lookups: 6 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

No ptr mechanism found in SPF record.
✓ 6 of 10 DNS lookups #2

SPF record needs 6 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

fail

p=none (_dmarc.hostnet.nl)

Found

Record: v=DMARC1; p=none; aspf=s; rua=mailto:hostnet.nl-ag@dmarc-reports.g1i.one; ruf=mailto:hostnet.nl-fr@dmarc-reports.g1i.one;
Found at: _dmarc.hostnet.nl
External report address: mailto:hostnet.nl-ag@dmarc-reports.g1i.one (authorized)
External report address: mailto:hostnet.nl-fr@dmarc-reports.g1i.one (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	none	Policy
rua	mailto:hostnet.nl-ag@dmarc-reports.g1i.one	Aggregate report addresses
ruf	mailto:hostnet.nl-fr@dmarc-reports.g1i.one	Failure report addresses
aspf	s	SPF alignment (r = relaxed, s = strict)

Checks

✗

Policy: none (monitoring only)

DMARC policy is set to 'none', which only monitors but doesn't protect against spoofing. Consider upgrading to 'quarantine' or ideally 'reject'.

#4
✓ Record published #5

DMARC record exists for this domain.
✓ Valid syntax #17

DMARC record syntax is valid.
✓ Aggregate reports enabled #19

Aggregate reports are sent to: mailto:hostnet.nl-ag@dmarc-reports.g1i.one
✓ External report addresses authorized #29

Report addresses in other domains have published their authorization.

DKIM

warn

Selectors: default, k1, s1, s2

Found

Selectors: default, k1, s1, s2
_domainkey: NOERROR

Selector	Key	Flags
default	RSA 1024 bits
k1	RSA 1024 bits
s1	RSA 2048 bits
s2	RSA 1024 bits

Checks

✓ Keys found: default, k1, s1, s2 #7

DKIM keys found for this domain with selectors: default, k1, s1, s2
!

1024-bit DKIM key

1024-bit RSA keys are the minimum and are considered weak today: default (1024 bits), k1 (1024 bits), 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 (1)
DS at parent: Yes
Algorithms: ECDSAP256SHA256 (13)
Key tags: 58501
Signatures valid until: 29 October 2026, 00:00 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 2026-10-29 #21

DNSKEY signatures are valid until 2026-10-29T00:00:00Z.

MX

warn

1 mail server

Found

Priority	Host	Records	Reverse DNS
10	mailfilter.hostnet.nl	A 91.184.19.251	mailfilter.hostnet.nl ✓

Checks

✓ 1 MX record #9

Found 1 MX records for this domain.
✓ All hosts resolve #10

All MX records resolve to valid IP addresses.
!

Hosts without IPv6

The following MX hosts could not be resolved to IPv6 addresses: mailfilter.hostnet.nl

#11
!

Single MX host, no backup

Only one MX record found. For better email reliability, consider adding at least one backup MX server.

#12
✓ At most 5 MX records #13

Found 1 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 1 MX address have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 1 of 1 MX hosts

Found

DANE (TLSA records)

MX host	TLSA	DNSSEC
mailfilter.hostnet.nl	3 1 1 e3f3620a9ffbf55a…	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 1 MX host 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