underware.nl

Checked 22 October 2026, 16:50 UTC · via 8.8.8.8
!Passed with warnings
25 passed 5 warnings 0 failed 1 info

SPF

pass

SPF record published

Found

Record
v=spf1 a mx a:spf.flexfilter.nl include:servers.mcsv.net -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

warn

p=quarantine (_dmarc.underware.nl)

Found

Record
v=DMARC1; p=quarantine; rua=mailto:dmarc@underware.nl; ruf=mailto:dmarc@underware.nl; sp=quarantine
Found at
_dmarc.underware.nl
TagValueMeaning
vDMARC1Version
pquarantinePolicy
spquarantineSubdomain policy
ruamailto:dmarc@underware.nlAggregate report addresses
rufmailto:dmarc@underware.nlFailure report addresses

Checks

  • !
    Policy: quarantine
    DMARC policy is set to 'quarantine'. Consider upgrading to 'reject' for stronger protection once you've verified legitimate emails are passing authentication.
    #4
  • ✓ 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@underware.nl
  • ✓ Subdomain policy: quarantine #20
    Subdomains are covered by policy 'quarantine'.
  • ✓ 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
12040, 22266
Signatures valid until
5 November 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 2026-11-05 #21
    DNSKEY signatures are valid until 2026-11-05T00:00:00Z.

MX

warn

2 mail servers

Found

PriorityHostRecordsReverse DNS
10srv1.flexfilter.nlA 62.84.240.181 A 185.89.6.110 A 62.84.244.16 A 62.84.244.25srv2a.flexfilter.nl ✓ srv3a.flexfilter.nl ✓ srv1a.flexfilter.nl ✓ srv1.flexfilter.nl ✓
10srv2.flexfilter.nlA 62.84.244.16 A 62.84.240.181 A 185.89.6.110srv1a.flexfilter.nl ✓ srv2a.flexfilter.nl ✓ srv3a.flexfilter.nl ✓

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: srv1.flexfilter.nl, srv2.flexfilter.nl
    #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 7 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
srv1.flexfilter.nl3 1 1 d03491259860ab30… 3 0 1 00ce84185d7b2f56…Yes
srv2.flexfilter.nl3 0 1 00ce84185d7b2f56… 3 1 1 d03491259860ab30…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