osiander.de

Checked 21 October 2026, 23:42 UTC · via 8.8.8.8
✗Problems found
18 passed 7 warnings 1 failed 1 info

SPF

pass

SPF record published

Found

Record
v=spf1 mx ip4:80.82.206.0/26 ip4:185.98.184.0/24 include:de._netblocks.mimecast.com include:spf.protection.outlook.com include:spf.hornetsecurity.com ~all
DNS lookups
4 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 4 of 10 DNS lookups #2
    SPF record needs 4 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

fail

p=none (_dmarc.osiander.de)

Found

Record
v=DMARC1; p=none;
Found at
_dmarc.osiander.de
TagValueMeaning
vDMARC1Version
pnonePolicy

Checks

  • ✗
    Policy: none (monitoring only)
    DMARC policy is set to 'none', which only monitors but doesn't protect against spoofing. Consider upgrading to 'quarantine' or ideally 'reject'.
    #4
  • ✓ Record published #5
    DMARC record exists for this domain.
  • ✓ Valid syntax #17
    DMARC record syntax is valid.
  • !
    No aggregate reports (rua)
    DMARC record has no rua tag, so you receive no aggregate reports about who sends mail as your domain. Add rua=mailto:...
    #19

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

5 mail servers

Found

PriorityHostRecordsReverse DNS
10mx01.hornetsecurity.comA 94.100.132.8mx01.hornetsecurity.com ✓
20mx02.hornetsecurity.comA 94.100.136.8mx02.hornetsecurity.com ✓
30mx03.hornetsecurity.comA 94.100.134.8mx03.hornetsecurity.com ✓
40mx04.hornetsecurity.comA 94.100.136.7mx04.hornetsecurity.com ✓
50osiander-de.mail.cloud.nospamproxy.comA 193.37.132.131 A 193.37.132.171de-s01-gw1.mail.cloud.nospamproxy.com ✓ de-s01-gw2.mail.cloud.nospamproxy.com ✓

Checks

  • ✓ 5 MX records #9
    Found 5 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: mx01.hornetsecurity.com, mx02.hornetsecurity.com, mx03.hornetsecurity.com, mx04.hornetsecurity.com, osiander-de.mail.cloud.nospamproxy.com
    #11
  • ✓ Redundant MX hosts #12
    Found 5 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 5 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 6 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 1 of 5 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
mx01.hornetsecurity.comnone-
mx02.hornetsecurity.comnone-
mx03.hornetsecurity.comnone-
mx04.hornetsecurity.comnone-
osiander-de.mail.cloud.nospamproxy.com3 1 1 7acc5ebfd159a58b… 3 1 1 4a8ccc4c8ae3d658… 3 1 1 897f916ec02bfb38… 3 1 1 15987f49fc954bba…Yes

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
  • !
    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
  • !
    Not all MX hosts use DANE
    These MX hosts publish no TLSA records, so mail to them is not protected by DANE: mx01.hornetsecurity.com, mx02.hornetsecurity.com, mx03.hornetsecurity.com, mx04.hornetsecurity.com.
    #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