zm-online.de

Checked 22 October 2026, 01:20 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

ns11.nameserver.de, ns12.nameserver.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns11.nameserver.de, ns12.nameserver.de
NS in the zone
ns11.nameserver.de, ns12.nameserver.de
NameserverAddressesNetwork (AS)Glue
ns11.nameserver.de212.223.44.219 2a02:708:0:26::2AS8741 ratiokontakt - ratiokontakt GmbH, DE AS8741 ratiokontakt - ratiokontakt GmbH, DE212.223.44.219 2a02:708:0:26::2
ns12.nameserver.de212.223.44.220 2a02:708:0:25::2AS8741 ratiokontakt - ratiokontakt GmbH, DE AS8741 ratiokontakt - ratiokontakt GmbH, DE212.223.44.220 2a02:708:0:25::2

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns11.nameserver.de, ns12.nameserver.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 one network
    all IPv4 addresses are in 212.223.44.0/24; all IPv6 addresses are in 2a02:708::/48. A single network failure takes all nameservers down; RFC 2182 recommends topologically separate networks (anycast setups are an exception).
    #10
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS8741 (ratiokontakt - ratiokontakt GmbH, DE): 4 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
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

warn

4 of 4 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns11.nameserver.de 212.223.44.219NOERROR, 1 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.7.3
ns11.nameserver.de 2a02:708:0:26::2NOERROR, 1 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.7.3
ns12.nameserver.de 212.223.44.220NOERROR, 1 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.7.3
ns12.nameserver.de 2a02:708:0:25::2NOERROR, 2 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.7.3

Checks

  • ✓ All respond #14
    All 4 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: ns11.nameserver.de: "PowerDNS Authoritative Server 4.7.3"; ns12.nameserver.de: "PowerDNS Authoritative Server 4.7.3". 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 2026073002 · primary ns11.nameserver.de

Found

Primary (MNAME)
ns11.nameserver.de
Contact (RNAME)
dnsmaster.ns12.nameserver.de
Serial
2026073002
Refresh / retry
28800 s / 7200 s
Expire
604800 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
ns11.nameserver.de (212.223.44.219)2026073002
ns11.nameserver.de (2a02:708:0:26::2)2026073002
ns12.nameserver.de (212.223.44.220)2026073002
ns12.nameserver.de (2a02:708:0:25::2)2026073002

Checks

  • ✓ Serial 2026073002 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 8h, retry 2h, expire 7d, negative TTL 1h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns11.nameserver.de is one of the listed nameservers.
  • ✓ Contact dnsmaster@ns12.nameserver.de #25
    The SOA RNAME dnsmaster.ns12.nameserver.de means dnsmaster@ns12.nameserver.de.
  • ✓ Date-based serial #26
    The serial 2026073002 follows the YYYYMMDDnn convention (2026-07-30).

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
212.223.44.219:53
TypeValueTTL
SOAns11.nameserver.de. dnsmaster.ns12.nameserver.de. 2026073002 28800 7200 604800 36003600
NSns12.nameserver.de.3600
NSns11.nameserver.de.3600
A185.215.158.10748741
MX0 zmonline-de0e.mail.protection.outlook.com.1800
TXT"v=spf1 a mx include:spf.crsend.com include:spf.protection.outlook.com include:spf-de.emailsignatures365.com ip4:82.141.39.251 ip4:212.184.65.35 ip4:157.97.32.106 ip4:212.91.225.100 -all"1800
TXT"MS=ms22314922"1800
TXT"google-site-verification=Ri55kBJ0EALfPqL_8A5RIeFQ4xrIfl5H07c7CfLVWCo"1800
TXT"domainVerification=b5fe448e-8779-4e61-bee4-026516437e51"1800

Checks

  • ✓ TTLs within range #32
    TTLs: A 13h32m21s, MX 30m, NS 1h. The NS TTL at the parent is 1d and in the zone 1h; 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