Mail domain report: ptb.de

SPF

pass

SPF record published

Found

Record: v=spf1 ip4:192.53.103.120/32 ip4:194.94.94.97/32 ip6:2001:638:610:bd01::120/128 ip6:2001:638:610:cdce::61/128 include:spf.smtp.net ~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.ptb.de)

Found

Record: v=DMARC1; p=quarantine; rua=mailto:dmarc@ptb.de
Found at: _dmarc.ptb.de

Tag	Value	Meaning
v	DMARC1	Version
p	quarantine	Policy
rua	mailto:dmarc@ptb.de	Aggregate report addresses

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@ptb.de
✓ Subdomain policy: quarantine #20

Subdomains are covered by policy 'quarantine'.
✓ Report addresses in own domain #29

All report addresses are in your own organizational domain.

DKIM

warn

No keys found under the checked selectors

Found

Selectors: None found
_domainkey: NOERROR

Checks

!

No key under common selectors

The _domainkey name exists but no DKIM key was found under the common selectors. Selectors are provider-specific; check yours with -selector.

#7

DNSSEC

warn

Signed, DS published at parent

Found

DNSKEY records: Yes (2)
DS at parent: Yes
Algorithms: RSASHA256 (8)
Key tags: 7284, 4561
Signatures valid until: 26 October 2026, 01:16 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 expire in 97h0m0s

DNSKEY signatures expire at 2026-10-26T01:16:11Z (in 97h0m0s). Check that re-signing works.

#21

MX

pass

2 mail servers

Found

Priority	Host	Records	Reverse DNS
10	mx1.bs.ptb.de	A 192.53.103.120 AAAA 2001:638:610:bd01::120	mx1.bs.ptb.de ✓ mx1.bs.ptb.de ✓
20	mx1.berlin.ptb.de	A 194.94.94.97 AAAA 2001:638:610:cdce::61	MX1.Berlin.PTB.DE ✓ mx1.berlin.ptb.de ✓

Checks

✓ 2 MX records #9

Found 2 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 2 MX records, which provides redundancy for email delivery.
✓ At most 5 MX records #13

Found 2 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 4 MX addresss have a PTR record that resolves back to them.

TLS

warn

MTA-STS testing · no TLS-RPT · DANE on 0 of 2 MX hosts

Found

MTA-STS record: v=STSv1; id=20251104153500Z
Policy URL: https://mta-sts.ptb.de/.well-known/mta-sts.txt
Mode: testing
Allowed MX: mx1.bs.ptb.de, mx1.berlin.ptb.de
Max age: 86400 seconds

DANE (TLSA records)

MX host	TLSA	DNSSEC
mx1.bs.ptb.de	none	-
mx1.berlin.ptb.de	none	-

Checks

✓ Record published #32

MTA-STS record found with id 20251104153500Z.
!

Policy in testing mode

With mode: testing, senders only report TLS problems (via TLS-RPT) and still deliver without TLS. Switch to mode: enforce once reports are clean.

#33
✓ All MX hosts covered #34

Every MX host matches an mx: line of the MTA-STS policy.
!

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
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