Mail domain report: jacks.nl

SPF

pass

SPF record published

Found

Record: v=spf1 include:spf.protection.outlook.com include:mail.zendesk.com include:spf.sendinblue.com mx -all
DNS lookups: 4 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

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

SPF record needs 4 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.jacks.nl)

Found

Record: v=DMARC1; p=quarantine; sp=none; rua=mailto:dmarc@mailinblue.com!10m; ruf=mailto:dmarc@mailinblue.com!10m; rf=afrf; pct=100; ri=86400
Found at: _dmarc.jacks.nl
External report address: mailto:dmarc@mailinblue.com!10m (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	quarantine	Policy
sp	none	Subdomain policy
pct	100	Percentage of mail the policy applies to
rua	mailto:dmarc@mailinblue.com!10m	Aggregate report addresses
ruf	mailto:dmarc@mailinblue.com!10m	Failure report addresses
rf	afrf	Failure report format
ri	86400	Report interval (seconds)

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@mailinblue.com!10m
!

Subdomains unprotected (sp=none)

DMARC subdomain policy is sp=none, so spoofed mail from subdomains is not blocked. Consider sp=quarantine or sp=reject.

#20
✓ External report addresses authorized #29

Report addresses in other domains have published their authorization.

DKIM

warn

Selectors: mail, s1, s2

Found

Selectors: mail, s1, s2
_domainkey: NOERROR

Selector	Key	Flags
mail	RSA 1024 bits
s1	RSA 2048 bits
s2	RSA 2048 bits

Checks

✓ Keys found: mail, s1, s2 #7

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

1024-bit DKIM key

1024-bit RSA keys are the minimum and are considered weak today: mail (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

warn

Signed, but no DS at parent

Found

DNSKEY records: Yes (2)
DS at parent: No
Algorithms: ECDSAP256SHA256 (13)
Key tags: 34505, 2371
Signatures valid until: 12 December 2026, 13:45 UTC

Checks

!

Signed, but no DS at parent

The zone is signed (DNSKEY present) but the parent has no DS record, so the chain of trust is incomplete. Publish the DS record at your registrar.

#8
✓ Signatures valid until 2026-12-12 #21

DNSKEY signatures are valid until 2026-12-12T13:45:48Z.

MX

warn

1 mail server

Found

Priority	Host	Records	Reverse DNS
0	jacks-nl.mail.protection.outlook.com	A 52.101.181.156 A 52.101.91.156 A 52.101.181.153 A 52.101.68.15 AAAA 2a01:111:f403:ca09::22 AAAA 2a01:111:f403:ca3c::8 AAAA 2a01:111:f403:ca09::a AAAA 2a01:111:f403:ca38::8	mail-wa4pr05cu00104.inbound.protection.outlook.com ✓ mail-maspr04cu00104.inbound.protection.outlook.com ✓ mail-wa4pr04cu00101.inbound.protection.outlook.com ✓ mail-db6pr03cu00107.inbound.protection.outlook.com ✓ mail-am7pr02cu00302.inbound.protection.outlook.com ✓ mail-zrxpr05cu00100.inbound.protection.outlook.com ✓ mail-am7pr02cu00202.inbound.protection.outlook.com ✓ mail-wa4pr04cu00100.inbound.protection.outlook.com ✓

Checks

✓ 1 MX record #9

Found 1 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.
!

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 8 MX addresss have a PTR record that resolves back to them.

TLS

info

MTA-STS enforce · TLS-RPT · DANE on 0 of 1 MX hosts

Found

MTA-STS record: v=STSv1; id=202609291447
Policy URL: https://mta-sts.jacks.nl/.well-known/mta-sts.txt
Mode: enforce
Allowed MX: jacks-nl.mail.protection.outlook.com
Max age: 604800 seconds
TLS-RPT record: v=TLSRPTv1; rua=mailto:mta-reports@jacks.nl

DANE (TLSA records)

MX host	TLSA	DNSSEC
jacks-nl.mail.protection.outlook.com	none	-

Checks

✓ Record published #32

MTA-STS record found with id 202609291447.
✓ Policy enforced #33

The MTA-STS policy is enforced and cached for 168h0m0s.
✓ All MX hosts covered #34

Every MX host matches an mx: line of the MTA-STS policy.
✓ Reports enabled #35

TLS reports are sent to: mailto:mta-reports@jacks.nl
i

Not used

No MX host publishes TLSA records. DANE lets senders verify your mail server's certificate through DNSSEC; it requires DNSSEC on the MX host's zone.

#36

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