plattform-lernende-systeme.de

Checked 21 October 2026, 23:50 UTC · via 8.8.8.8
!Passed with warnings
19 passed 3 warnings 0 failed 7 info

Registration

info

.de country-code

Found

TLD
.de (country-code)
ICANN policies apply
no

Checks

  • i
    .de is a country-code TLD (ccTLD)
    Country-code TLD: governed by its local registry under national policy, not by an ICANN contract. Registrar accreditation, dispute resolution and RDAP/WHOIS rules are set by the registry.
    #1
  • ✓ TLD delegated and signed #2
    .de is delegated in the root zone and DNSSEC-signed.
  • i
    Registration data not available
    No registration data via RDAP: the registry of .de offers no RDAP service. Many ccTLD registries don't offer RDAP; check the registry's WHOIS instead.
    #3

Delegation

warn

dns01.dns-on.de, dns02.dns-on.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns01.dns-on.de, dns02.dns-on.de
NS in the zone
dns01.dns-on.de, dns02.dns-on.de
NameserverAddressesNetwork (AS)Glue
dns01.dns-on.de84.38.79.94AS204119 ISPONE - ispOne business GmbH, DE-
dns02.dns-on.de84.38.64.94AS204119 ISPONE - ispOne business GmbH, DE-

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: dns01.dns-on.de, dns02.dns-on.de.
    #6
  • ✓ Parent and zone agree #7
    The parent delegation and the zone's NS records list the same nameservers.
  • ✓ No glue needed #8
    All nameservers are outside the zone, so no glue records are needed.
  • ✓ All names resolve #9
    Every nameserver name has an address and is not an alias.
  • ✓ Nameservers in different networks #10
    The nameservers are spread over 2 IPv4 /24s and 0 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS204119 (ISPONE - ispOne business GmbH, DE): 2 addresses). An outage or attack on that network affects all nameservers; large anycast providers mitigate this, but a secondary DNS provider adds independence.
    #11
  • i
    All nameserver names under .de
    All nameserver names are under one TLD, so a problem with that TLD also makes the nameservers unreachable. Some operators use names under two TLDs for extra resilience.
    #12
  • !
    No IPv6
    None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.
    #13

Nameservers

warn

2 of 2 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns01.dns-on.de 84.38.79.94NOERROR, 4 ms, authoritativenoyes / yesrefused9.16.50-Debian
dns02.dns-on.de 84.38.64.94NOERROR, 4 ms, authoritativenoyes / yesrefused9.16.50-Debian

Checks

  • ✓ All respond #14
    All 2 nameserver addresses answered.
  • ✓ All authoritative #15
    Every responding nameserver answers authoritatively for the zone.
  • ✓ No recursion #16
    The nameservers do not answer recursive queries for other domains.
  • !
    Software version disclosed
    These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: dns01.dns-on.de: "9.16.50-Debian"; dns02.dns-on.de: "9.16.50-Debian". Hide or replace the version string.
    #17
  • ✓ Zone transfers refused #18
    No nameserver allows a zone transfer to the public.
  • ✓ TCP supported #19
    All nameservers answer over TCP.
  • ✓ EDNS supported #20
    All nameservers support EDNS(0).
  • ✓ Public addresses #21
    All nameserver addresses are publicly routable.

SOA

pass

serial 2017090552 · primary dns01.dns-on.de

Found

Primary (MNAME)
dns01.dns-on.de
Contact (RNAME)
hostmaster.dns-on.de
Serial
2017090552
Refresh / retry
10800 s / 1800 s
Expire
604800 s
Negative TTL
1800 s

Serial per nameserver

NameserverSerial
dns01.dns-on.de (84.38.79.94)2017090552
dns02.dns-on.de (84.38.64.94)2017090552

Checks

  • ✓ Serial 2017090552 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 30m, expire 7d, negative TTL 30m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns01.dns-on.de is one of the listed nameservers.
  • ✓ Contact hostmaster@dns-on.de #25
    The SOA RNAME hostmaster.dns-on.de means hostmaster@dns-on.de.
  • ✓ Date-based serial #26
    The serial 2017090552 follows the YYYYMMDDnn convention (2017-09-05).

DNSSEC

warn

Not signed

Found

Validated by resolver
no

Checks

  • !
    Not signed
    The zone is not signed with DNSSEC, so answers can be spoofed. Enable DNSSEC at your DNS provider and publish the DS record at your registrar.
    #27

Records

info

9 records at the apex

Found

Read from
84.38.79.94:53
TypeValueTTL
SOAdns01.dns-on.de. hostmaster.dns-on.de. 2017090552 10800 1800 604800 180086400
NSdns01.dns-on.de.1800
NSdns02.dns-on.de.1800
A84.38.65.531800
MX20 smtp01.adminflex.de.86400
MX30 smtp02.adminflex.de.86400
MX10 mailin.adminflex.de.86400
TXT"brevo-code:15322d4a9f593088828605df73667def"3600
TXT"v=spf1 mx/24 ~all"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 30m, MX 1d, NS 30m. The NS TTL at the parent is 1d and in the zone 30m; resolvers may use either.
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • i
    Wildcard record
    A random name under the zone resolves, so there is a wildcard (*) record. Typos and non-existent hosts resolve too, which can confuse mail and certificate checks.
    #34
  • i
    No CAA records
    Without CAA records any certificate authority may issue certificates for this domain. A CAA record limits issuance to the CAs you use.
    #35