lrz.de

Checked 21 October 2026, 23:20 UTC · via 8.8.8.8
✗Problems found
23 passed 3 warnings 1 failed 2 info

SPF

info

SPF record published

Found

Record
v=spf1 redirect=_spf.mail.lrz.de
DNS lookups
1 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 1 of 10 DNS lookups #2
    SPF record needs 1 DNS lookups (limit is 10).
  • i
    Delegated via redirect
    SPF record has no 'all' mechanism but redirects to _spf.mail.lrz.de, whose policy applies.
    #3
  • ✓ 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.lrz.de)

Found

Record
v=DMARC1; p=none; rua=mailto:dmarc-reports@lrz.de
Found at
_dmarc.lrz.de
TagValueMeaning
vDMARC1Version
pnonePolicy
ruamailto:dmarc-reports@lrz.deAggregate report addresses

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:dmarc-reports@lrz.de
  • ✓ Report addresses in own domain #29
    All report addresses are in your own organizational domain.

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

pass

Signed, DS published at parent

Found

DNSKEY records
Yes (2)
DS at parent
Yes
Algorithms
RSASHA256 (8)
Key tags
42814, 57448
Signatures valid until
17 December 2026, 12:42 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 2026-12-17 #21
    DNSKEY signatures are valid until 2026-12-17T12:42:06Z.

MX

pass

2 mail servers

Found

PriorityHostRecordsReverse DNS
100postrelay1.lrz.deA 129.187.254.158 A 129.187.255.160 AAAA 2001:4ca0:0:103::81bb:ffa0 AAAA 2001:4ca0:0:103:0:25:1:1postrelay1a.lrz.de ✓ postrelay1b.lrz.de ✓ postrelay1b.lrz.de ✓ postrelay1a.lrz.de ✓
100postrelay2.lrz.deA 129.187.254.159 A 129.187.255.161 AAAA 2001:4ca0:0:103::81bb:ffa1 AAAA 2001:4ca0:0:103:0:25:1:2postrelay2a.lrz.de ✓ postrelay2b.lrz.de ✓ postrelay2b.lrz.de ✓ postrelay2a.lrz.de ✓

Checks

  • ✓ 2 MX records #9
    Found 2 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.
  • ✓ 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.
  • ✓ Reverse DNS confirmed #30
    All 8 MX addresss have a PTR record that resolves back to them.

TLS

warn

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

Found

DANE (TLSA records)

MX hostTLSADNSSEC
postrelay1.lrz.de3 1 1 3d805975a26979f6…Yes
postrelay2.lrz.de3 1 1 aa00d3fd8f372d50…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
  • ✓ DANE on all MX hosts #36
    All 2 MX hosts publish DNSSEC-validated TLSA records.

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