SurfaceMap › s › snn.nl

snn.nl

Checked 2026-10-22 16:10 UTC · first added 2026-10-21
!Check could not complete

Domain & DNS

error

26 passed 1 warn 1 failed 1 errors

lookups failed for rdap; results are incomplete

Areas

iRegistration iDelegation ✗Nameservers ✓SOA !DNSSEC iRecords

Problems

  • ✗
    No DNS over TCP
    Nameservers · DNS over TCP is required (RFC 7766); without it, large answers such as DNSSEC responses fail. Not answering over TCP: ns2.duocast.net (2a01:1b1:4418::53): read tcp [2a01:4f8:1c1c:eebf::1]:34710->[2a01:1b1:4418::53]:53: read: connection reset by peer.
    #19
  • !
    NSEC3 with extra iterations or salt
    DNSSEC · NSEC3 uses 1 iteration and a 2-byte salt. RFC 9276 recommends 0 iterations and no salt: extra iterations cost resolvers CPU and add no real protection, and some validators treat high counts as insecure.
    #31

Recent checks

!

Full report

Domain & DNS report for snn.nl ›

Mail

fail

26 passed 5 warn 1 failed

Areas

✗SPF !DMARC !DKIM ✓DNSSEC !MX !TLS iBIMI

Problems

  • ✗
    12 DNS lookups, over the limit of 10
    SPF · SPF record needs 12 DNS lookups (including nested includes), more than the limit of 10. Receivers will return a permerror; reduce includes or flatten the record.
    #2
  • !
    Policy: quarantine
    DMARC · DMARC policy is set to 'quarantine'. Consider upgrading to 'reject' for stronger protection once you've verified legitimate emails are passing authentication.
    #4
  • !
    Single MX host, no backup
    MX · Only one MX record found. For better email reliability, consider adding at least one backup MX server.
    #12
  • !
    1024-bit DKIM key
    DKIM · 1024-bit RSA keys are the minimum and are considered weak today: selector2 (1024 bits). Rotate to a 2048-bit key.
    #23
  • !
    Not configured
    TLS · 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
    TLS · 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

Recent checks

✗

Full report

Mail report for snn.nl ›