bitzer.de

.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

dns1.lf.net, dns2.lf.net, dns3.lf.net

Found

Parent zone

de

Delegation from

a.nic.de (194.0.0.53)

NS at the parent

dns1.lf.net, dns2.lf.net, dns3.lf.net

NS in the zone

dns1.lf.net, dns2.lf.net, dns3.lf.net

Checks

• ✓ 3 nameservers #6

  Delegated to dns1.lf.net, dns2.lf.net, dns3.lf.net.
• ✓ 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 3 IPv4 /24s and 1 IPv6 /48.
• ✓ 2 autonomous systems #11

  The nameservers are spread over: AS12374 (LFNET-AS01 - LF.net Netzwerksysteme GmbH, DE): 3 addresses; AS16509 (AMAZON-02 - Amazon.com, Inc., US): 1 address.
• i

  All nameserver names under .net

  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
• i

  Partly IPv6

  These nameservers have no IPv6 address: dns2.lf.net, dns3.lf.net.

  #13

4 of 4 addresses answer authoritatively

Found

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.
• i

  Identifying string disclosed

  These nameservers answer version queries with a string that is not a version number: dns1.lf.net: "none"; dns2.lf.net: "null"; dns3.lf.net: "null".

  #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.

serial 2026102100 · primary ns.lf.net

Found

Primary (MNAME)

ns.lf.net

Contact (RNAME)

hostmaster.lf.net

Serial

2026102100

Refresh / retry

86400 s / 7200 s

Expire

604800 s

Negative TTL

600 s

Serial per nameserver

Checks

• ✓ Serial 2026102100 everywhere #22

  All nameservers serve the same version of the zone.
• ✓ Timers within recommendations #23

  SOA refresh 1d, retry 2h, expire 7d, negative TTL 10m.
• i

  Hidden master

  The primary nameserver ns.lf.net is not listed as a nameserver: a hidden master that only feeds the public secondaries. That is a common setup; make sure it is not reachable for zone transfers from outside.

  #24
• ✓ Contact hostmaster@lf.net #25

  The SOA RNAME hostmaster.lf.net means hostmaster@lf.net.
• ✓ Date-based serial #26

  The serial 2026102100 follows the YYYYMMDDnn convention (2026-10-21).

21 records at the apex

Found

Read from

212.9.160.10:53

Checks

• ✓ TTLs within range #32

  TTLs: A 1h, MX 1h, 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.
• ✓ No wildcard #34

  Names that don't exist return NXDOMAIN.
• 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