computable.nl

Checked 21 October 2026, 21:00 UTC · via 8.8.8.8
!Passed with warnings
27 passed 3 warnings 0 failed 3 info

SPF

pass

SPF record published

Found

Record
v=spf1 include:servers.mcsv.net mx ip4:87.233.245.148 ip4:87.233.245.149 ip4:87.233.245.153 ip4:87.233.150.212 ip4:87.233.150.213 ip4:87.233.150.216 ip4:87.233.150.218 include:spf.protection.outlook.com -all
DNS lookups
3 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 3 of 10 DNS lookups #2
    SPF record needs 3 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.computable.nl)

Found

Record
v=DMARC1; p=reject; fo=1; rua=mailto:rua+computable.nl@dmarc.barracudanetworks.com; ruf=mailto:ruf+computable.nl@dmarc.barracudanetworks.com
Found at
_dmarc.computable.nl
External report address
mailto:rua+computable.nl@dmarc.barracudanetworks.com (authorized)
External report address
mailto:ruf+computable.nl@dmarc.barracudanetworks.com (authorized)
TagValueMeaning
vDMARC1Version
prejectPolicy
ruamailto:rua+computable.nl@dmarc.barracudanetworks.comAggregate report addresses
rufmailto:ruf+computable.nl@dmarc.barracudanetworks.comFailure report addresses
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:rua+computable.nl@dmarc.barracudanetworks.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

Selectors: k1, selector1

Found

Selectors
k1, selector1
_domainkey
NOERROR
SelectorKeyFlags
k1RSA 1024 bits
selector1RSA 2048 bits

Checks

  • ✓ Keys found: k1, selector1 #7
    DKIM keys found for this domain with selectors: k1, selector1
  • !
    1024-bit DKIM key
    1024-bit RSA keys are the minimum and are considered weak today: k1 (1024 bits). Rotate to a 2048-bit key.
    #23
  • ✓ No problematic flags #24
    No keys in test mode, revoked, or limited to SHA-1.

DNSSEC

pass

Signed, DS published at parent

Found

DNSKEY records
Yes (2)
DS at parent
Yes
Algorithms
ECDSAP256SHA256 (13)
Key tags
11718, 31256
Signatures valid until
29 October 2026, 00:00 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 2026-10-29 #21
    DNSKEY signatures are valid until 2026-10-29T00:00:00Z.

MX

warn

2 mail servers

Found

PriorityHostRecordsReverse DNS
10d331534.a.ess.de.barracudanetworks.comA 18.185.115.251 A 18.185.115.250 A 18.185.115.252mail.ess.de.barracuda.com ✓ mail.ess.de.barracuda.com ✓ mail.ess.de.barracuda.com ✓
20d331534.b.ess.de.barracudanetworks.comA 18.185.115.251 A 18.185.115.250 A 18.185.115.252mail.ess.de.barracuda.com ✓ mail.ess.de.barracuda.com ✓ mail.ess.de.barracuda.com ✓

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: d331534.a.ess.de.barracudanetworks.com, d331534.b.ess.de.barracudanetworks.com
    #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.
  • ✓ 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 0 of 2 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
d331534.a.ess.de.barracudanetworks.comnone-
d331534.b.ess.de.barracudanetworks.comnone-

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