n18.de

Checked 21 October 2026, 23:31 UTC · via 8.8.8.8
✗Problems found
20 passed 6 warnings 1 failed 3 info

SPF

warn

SPF record published

Found

Record
v=spf1 ip4=176.9.1.168 include:mail.n18.de include:lists.n18.de -all
DNS lookups
3 of 10
Void lookups
1 of 2
Problem
include:mail.n18.de does not exist or has no records

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • !
    3 of 10 DNS lookups, with problems
    SPF record needs 3 DNS lookups (limit is 10). Problems found: include:mail.n18.de does not exist or has no records.
    #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.
  • !
    1 void lookup
    1 include/redirect target does not exist or has no records (limit is 2). This usually is a stale include; remove it.
    #26
  • ✓ No overly broad IP ranges #27
    All ip4/ip6 ranges are narrow enough.

DMARC

fail

p=none (_dmarc.n18.de)

Found

Record
v=DMARC1;p=none;sp=reject;pct=100;rua=mailto:df2et@n18.de;ruf=mailto:df2et@n18.de;ri=86400;aspf=r;adkim=r;fo=1
Found at
_dmarc.n18.de
TagValueMeaning
vDMARC1Version
pnonePolicy
sprejectSubdomain policy
pct100Percentage of mail the policy applies to
ruamailto:df2et@n18.deAggregate report addresses
rufmailto:df2et@n18.deFailure report addresses
adkimrDKIM alignment (r = relaxed, s = strict)
aspfrSPF alignment (r = relaxed, s = strict)
fo1Failure reporting options
ri86400Report interval (seconds)

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.
  • ✓ Aggregate reports enabled #19
    Aggregate reports are sent to: mailto:df2et@n18.de
  • ✓ Report addresses in own domain #29
    All report addresses are in your own organizational domain.

DKIM

warn

Selectors: email

Found

Selectors
email
_domainkey
NOERROR
SelectorKeyFlags
emailRSA 2048 bitstest mode (t=y), h=sha256

Checks

  • ✓ Keys found: email #7
    DKIM keys found for this domain with selectors: email
  • ✓ Strong keys #23
    DKIM keys are strong enough: email: RSA 2048 bits.
  • !
    Key in test mode
    These keys have t=y, so receivers treat DKIM failures as a test: email. Remove t=y once DKIM works.
    #24

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

1 mail server

Found

PriorityHostRecordsReverse DNS
10mail.n18.deA 176.9.1.168 AAAA 2a01:4f8:141:31a1:fb68:1836:4:18mail.n18.de ✓ mail.n18.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.
  • ✓ 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 2 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 hostTLSADNSSEC
mail.n18.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