dfl.de

Checked 21 October 2026, 22:14 UTC · via 8.8.8.8
✗Problems found
21 passed 5 warnings 1 failed 3 info

SPF

pass

SPF record published

Found

Record
v=spf1 ip4:80.154.68.12/32 ip4:194.8.207.200/32 ip4:54.240.98.234/32 ip4:54.240.98.235/32 include:de.dfl.spf.martrexodns.com ip4:80.155.8.32/27 ip4:80.72.141.107/32 include:_spf.proxy.nospamproxy.com include:_spf.atlassian.net include:spf.lamapoll.de include:mail.zendesk.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

warn

p=quarantine (_dmarc.dfl.de)

Found

Record
v=DMARC1; p=quarantine; rua=mailto:dmarc@dfl.de; ruf=mailto:dmarc@dfl.de; fo=1
Found at
_dmarc.dfl.de
TagValueMeaning
vDMARC1Version
pquarantinePolicy
ruamailto:dmarc@dfl.deAggregate report addresses
rufmailto:dmarc@dfl.deFailure report addresses
fo1Failure reporting options

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@dfl.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

fail

No keys found under the checked selectors

Found

Selectors
None found
_domainkey
NXDOMAIN

Checks

  • ✗
    No DKIM keys published
    _domainkey.dfl.de does not exist (NXDOMAIN), so no DKIM keys are published. DKIM helps prevent email spoofing. Configure DKIM with your email service provider.
    #7

DNSSEC

warn

Not signed

Found

DNSKEY records
No (0)
DS at parent
No

Checks

  • !
    Not enabled
    DNSSEC is not enabled for this domain. Consider enabling DNSSEC to protect against DNS spoofing attacks.
    #8

MX

warn

2 mail servers

Found

PriorityHostRecordsReverse DNS
10securemail03.dfl.deA 13.93.42.35no PTR
20securemail04.dfl.deA 20.113.56.82no PTR

Checks

  • ✓ 2 MX records #9
    Found 2 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: securemail03.dfl.de, securemail04.dfl.de
    #11
  • ✓ 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.
  • !
    Addresses without reverse DNS
    These MX addresses have no PTR record, which many receivers treat as a spam signal: 13.93.42.35 (securemail03.dfl.de), 20.113.56.82 (securemail04.dfl.de). Ask your hosting provider to set one.
    #30

TLS

warn

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

Found

DANE (TLSA records)

MX hostTLSADNSSEC
securemail03.dfl.denone-
securemail04.dfl.denone-

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

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