Mail domain report: gdch.de

SPF

pass

SPF record published

Found

Record: v=spf1 include:_spf.prod.hydra.sophos.com ip4:185.219.102.128/25 ip4:148.251.113.148 ip4:62.96.227.162 a:mail.gdch.de ip4:77.32.203.80 include:spf.u2d.de include:spfa.myconvento.com ~all
DNS lookups: 8 of 10
Void lookups: 0 of 2

Checks

✓ No deprecated ptr mechanism #1

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

SPF record needs 8 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

pass

p=reject (_dmarc.gdch.de)

Found

Record: v=DMARC1; p=reject; sp=reject; adkim=r; aspf=r; pct=100; rua=mailto:d34609ae@in.mailhardener.com,mailto:re+gsueqqkt2jw@dmarc.postmarkapp.com,mailto:dmarc@mailinblue.com; ruf=mailto:d34609ae@in.mailhardener.com; fo=1; ri=3600
Found at: _dmarc.gdch.de
External report address: mailto:d34609ae@in.mailhardener.com (authorized)
External report address: mailto:re+gsueqqkt2jw@dmarc.postmarkapp.com (authorized)
External report address: mailto:dmarc@mailinblue.com (authorized)

Tag	Value	Meaning
v	DMARC1	Version
p	reject	Policy
sp	reject	Subdomain policy
pct	100	Percentage of mail the policy applies to
rua	mailto:d34609ae@in.mailhardener.com,mailto:re+gsueqqkt2jw@dmarc.postmarkapp.com,mailto:dmarc@mailinblue.com	Aggregate report addresses
ruf	mailto:d34609ae@in.mailhardener.com	Failure report addresses
adkim	r	DKIM alignment (r = relaxed, s = strict)
aspf	r	SPF alignment (r = relaxed, s = strict)
fo	1	Failure reporting options
ri	3600	Report interval (seconds)

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:d34609ae@in.mailhardener.com, mailto:re+gsueqqkt2jw@dmarc.postmarkapp.com, mailto:dmarc@mailinblue.com
✓ 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

Selectors: mail

Found

Selectors: mail
_domainkey: NOERROR

Selector	Key	Flags
mail	RSA 1024 bits

Checks

✓ Keys found: mail #7

DKIM keys found for this domain with selectors: mail
!

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

pass

Signed, DS published at parent

Found

DNSKEY records: Yes (2)
DS at parent: Yes
Algorithms: RSASHA256 (8)
Key tags: 47689, 19972
Signatures valid until: 5 November 2026, 09:15 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 2026-11-05 #21

DNSKEY signatures are valid until 2026-11-05T09:15:58Z.

MX

warn

1 mail server

Found

Priority	Host	Records	Reverse DNS
10	mail.gdch.de	A 62.96.227.162	mail.gdch.de ✓

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: mail.gdch.de

#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

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

Found

MTA-STS record: v=STSv1; id=202606242047;
Policy URL: https://mta-sts.gdch.de/.well-known/mta-sts.txt
Mode: testing
Allowed MX: mail.gdch.de, *.gdch.de
Max age: 31536000 seconds
TLS-RPT record: v=TLSRPTv1; rua=mailto:tlsrpt@in.mailhardener.com

DANE (TLSA records)

MX host	TLSA	DNSSEC
mail.gdch.de	none	-

Checks

✓ Record published #32

MTA-STS record found with id 202606242047.
!

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.
✓ Reports enabled #35

TLS reports are sent to: mailto:tlsrpt@in.mailhardener.com
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