SurfaceMap › d › deltares.nl

deltares.nl

Checked 2026-10-21 21:00 UTC · first added 2026-10-21
!Check could not complete

Domain & DNS

error

23 passed 4 warn 0 failed 1 errors

lookups failed for rdap; results are incomplete

Areas

iRegistration !Delegation ✓Nameservers !SOA !DNSSEC ✓Records

Problems

  • !
    Nameservers in one network
    Delegation · all IPv4 addresses are in 136.231.2.0/24. A single network failure takes all nameservers down; RFC 2182 recommends topologically separate networks (anycast setups are an exception).
    #10
  • !
    No IPv6
    Delegation · None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.
    #13
  • !
    Serials differ
    SOA · The nameservers serve different versions of the zone: 2026101403 on ns2.deltares.nl (136.231.2.117); 2026101651 on ns1.deltares.nl (136.231.2.116). This is normal for a few minutes after a change; if it lasts, zone transfers to the secondaries are failing.
    #22
  • !
    Deprecated algorithm
    DNSSEC · SHA-1 based algorithms are deprecated and rejected by some validators: RSASHA1-NSEC3-SHA1 (7). Roll over to ECDSAP256SHA256 (13).
    #29

Recent checks

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Full report

Domain & DNS report for deltares.nl ›

Mail

warn

26 passed 4 warn 0 failed

Areas

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

Problems

  • !
    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: mail (1024 bits), selector1 (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

Recent checks

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Full report

Mail report for deltares.nl ›