osnabrueck.de

Checked 21 October 2026, 23:42 UTC · via 8.8.8.8
!Passed with warnings
24 passed 5 warnings 0 failed 2 info

SPF

pass

SPF record published

Found

Record
v=spf1 a mx a:osnabrueck.marcant.net ip4:194.45.37.19 ip4:92.205.193.153 include:spf.itebo.de include:spfhard.crsend.com ip4:80.67.18.126 ip4:185.121.204.0/24 ip4:91.249.248.100 include:_se_net.axiell.com include:_uk.axiell.com include:spf.protection.outlook.com ip4:87.54.30.56 include:spf.niedersachsen.de -all
DNS lookups
9 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 9 of 10 DNS lookups #2
    SPF record needs 9 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.osnabrueck.de)

Found

Record
v=DMARC1; p=reject; rua=mailto:dmarc@osnabrueck.de,mailto:dmarc@25reports.com; fo=1; adkim=r; aspf=r
Found at
_dmarc.osnabrueck.de
External report address
mailto:dmarc@25reports.com (authorized)
TagValueMeaning
vDMARC1Version
prejectPolicy
ruamailto:dmarc@osnabrueck.de,mailto:dmarc@25reports.comAggregate report addresses
adkimrDKIM alignment (r = relaxed, s = strict)
aspfrSPF alignment (r = relaxed, s = strict)
fo1Failure reporting options

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:dmarc@osnabrueck.de, mailto:dmarc@25reports.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

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

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

3 mail servers

Found

PriorityHostRecordsReverse DNS
20mail1x.osnabrueck.deA 80.228.87.5mail1x.osnabrueck.de ✓
20mail2x.osnabrueck.deA 80.228.87.4mail2x.osnabrueck.de ✓
30mail3x.osnabrueck.deA 80.228.87.54mail3x.osnabrueck.de ✓

Checks

  • ✓ 3 MX records #9
    Found 3 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: mail1x.osnabrueck.de, mail2x.osnabrueck.de, mail3x.osnabrueck.de
    #11
  • ✓ Redundant MX hosts #12
    Found 3 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 3 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 3 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 0 of 3 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
mail1x.osnabrueck.denone-
mail2x.osnabrueck.denone-
mail3x.osnabrueck.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

warn

https://www.osnabrueck.de/fileadmin/user_upload/bimi/stadtrad.svg

Found

Record
v=BIMI1; l=https://www.osnabrueck.de/fileadmin/user_upload/bimi/stadtrad.svg; a=;
Found at
default._bimi.osnabrueck.de
Logo
https://www.osnabrueck.de/fileadmin/user_upload/bimi/stadtrad.svg

Checks

  • !
    No certificate (a=)
    The logo is published without a Verified Mark Certificate. Gmail and Apple Mail only show BIMI logos with a VMC or CMC; Yahoo shows it without one.
    #38
  • ✓ DMARC meets BIMI requirements #39
    DMARC is enforced on all mail, as BIMI requires.