dl3mc.de

ns1.xiweb.de, ns2.xiweb.de

Found

Parent zone

de

Delegation from

a.nic.de (194.0.0.53)

NS at the parent

ns1.xiweb.de, ns2.xiweb.de

NS in the zone

ns1.xiweb.de, ns2.xiweb.de

Checks

• i

  2 nameservers

  Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns1.xiweb.de, ns2.xiweb.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 185.14.13.0/24; all IPv6 addresses are in 2a02:f880::/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 (AS61244 (EURO-SAT - Manfred Casper trading as EURO-SAT, 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.

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.
• !

  Software version disclosed

  These nameservers report their software version via version.bind/version.server, which helps attackers find known vulnerabilities: ns1.xiweb.de: "9.20.29-1~deb13u1-Debian"; ns2.xiweb.de: "9.20.29-1~deb13u1-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.

serial 2026050401 · primary ns1.xiweb.de

Found

Primary (MNAME)

ns1.xiweb.de

Contact (RNAME)

info.xiweb.de

Serial

2026050401

Refresh / retry

600 s / 300 s

Expire

604800 s

Negative TTL

600 s

Serial per nameserver

Checks

• ✓ Serial 2026050401 everywhere #22

  All nameservers serve the same version of the zone.
• !

  Unusual SOA timers

  refresh 10m is outside 20m–1d. Current values: refresh 10m, retry 5m, expire 7d, negative TTL 10m.

  #23
• ✓ Primary is a public nameserver #24

  The primary nameserver ns1.xiweb.de is one of the listed nameservers.
• ✓ Contact info@xiweb.de #25

  The SOA RNAME info.xiweb.de means info@xiweb.de.
• ✓ Date-based serial #26

  The serial 2026050401 follows the YYYYMMDDnn convention (2026-05-04).

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