Mail domain report: strato.de

SPF

fail

SPF record published

Found

Record: v=spf1 a:ap4-p00-ob.smtp.rzone.de a:ap4-p02-ob.smtp.rzone.de a:ap4-p03-ob.smtp.rzone.de a:ap6-p00-ob.smtp.rzone.de a:ap6-p02-ob.smtp.rzone.de a:ap6-p03-ob.smtp.rzone.de include:_spf.google.com include:_spf-corporate.ionos.com ~all
DNS lookups: 13 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

No ptr mechanism found in SPF record.
✗

13 DNS lookups, over the limit of 10

SPF record needs 13 DNS lookups (including nested includes), more than the limit of 10. Receivers will return a permerror; reduce includes or flatten the record.

#2
✓ 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

pass

p=reject (_dmarc.strato.de)

Found

Record: v=DMARC1; p=reject; pct=100; adkim=r; rua=mailto:strato_de@dmarc-reports.strato.de; ruf=mailto:processed@strato-dmarc.de
Found at: _dmarc.strato.de
External report address: mailto:processed@strato-dmarc.de (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	reject	Policy
pct	100	Percentage of mail the policy applies to
rua	mailto:strato_de@dmarc-reports.strato.de	Aggregate report addresses
ruf	mailto:processed@strato-dmarc.de	Failure report addresses
adkim	r	DKIM alignment (r = relaxed, s = strict)

Checks

✓ Policy: reject #4

DMARC policy is set to 'reject', which provides the strongest protection against email spoofing.
✓ 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:strato_de@dmarc-reports.strato.de
✓ Subdomain policy: reject #20

Subdomains are covered by policy 'reject'.
✓ External report addresses authorized #29

Report addresses in other domains have published their authorization.

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

pass

Signed, DS published at parent

Found

DNSKEY records: Yes (2)
DS at parent: Yes
Algorithms: RSASHA256 (8)
Key tags: 6982, 44409
Signatures valid until: 29 October 2026, 06:55 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 2026-10-29T06:55:03Z.

MX

warn

1 mail server

Found

Priority	Host	Records	Reverse DNS
1	smtp.google.com	A 142.251.127.26 A 142.251.127.27 AAAA 2a00:1450:4001:c21::1b AAAA 2a00:1450:4001:c21::1a	lcfrai-in-f26.1e100.net ✓ lcfrai-in-f27.1e100.net ✓ lcfrai-in-f27.1e100.net ✓ lcfrai-in-f26.1e100.net ✓

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

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 0 of 1 MX hosts

Found

DANE (TLSA records)

MX host	TLSA	DNSSEC
smtp.google.com	none	-

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
i

Not configured

TLS-RPT lets senders report TLS delivery problems to you. It is most useful together with MTA-STS or DANE.

#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

pass

https://vmc.digicert.com/2f23a705-721a-4a67-884e-dc7cf3c34dab.svg

Found

Record: v=BIMI1;l=https://vmc.digicert.com/2f23a705-721a-4a67-884e-dc7cf3c34dab.svg;a=https://vmc.digicert.com/2f23a705-721a-4a67-884e-dc7cf3c34dab.pem
Found at: default._bimi.strato.de
Logo: https://vmc.digicert.com/2f23a705-721a-4a67-884e-dc7cf3c34dab.svg
Certificate: https://vmc.digicert.com/2f23a705-721a-4a67-884e-dc7cf3c34dab.pem

Checks

✓ Logo and certificate published #38

BIMI logo: https://vmc.digicert.com/2f23a705-721a-4a67-884e-dc7cf3c34dab.svg; certificate: https://vmc.digicert.com/2f23a705-721a-4a67-884e-dc7cf3c34dab.pem
✓ DMARC meets BIMI requirements #39

DMARC is enforced on all mail, as BIMI requires.