Domain report: c3d2.de

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

pass

ns.c3d2.de, ns.spaceboyz.net, ns1.supersandro.de, ns2.zentralwerk.org

Found

Parent zone: de
Delegation from: a.nic.de (194.0.0.53)
NS at the parent: ns.c3d2.de, ns.spaceboyz.net, ns1.supersandro.de, ns2.zentralwerk.org
NS in the zone: ns.c3d2.de, ns.spaceboyz.net, ns1.supersandro.de, ns2.zentralwerk.org

Nameserver	Addresses	Network (AS)	Glue
ns.c3d2.de	45.158.40.165 2a0f:5382:acab:1400::a5	AS208135 fluepke-net - Carl Fabian Luepke, DE AS208135 fluepke-net - Carl Fabian Luepke, DE	45.158.40.165 2a0f:5382:acab:1400::a5
ns.spaceboyz.net	37.27.116.148 2a01:4f9:3070:2728::4	AS24940 HETZNER-AS - Hetzner Online GmbH, DE AS24940 HETZNER-AS - Hetzner Online GmbH, DE	-
ns1.supersandro.de	188.34.196.104 2a01:4f8:1c1c:1d38::1	AS24940 HETZNER-AS - Hetzner Online GmbH, DE AS24940 HETZNER-AS - Hetzner Online GmbH, DE	188.34.196.104 2a01:4f8:1c1c:1d38::1
ns2.zentralwerk.org	138.201.192.243 2a01:4f8:172:3a90::1	AS24940 HETZNER-AS - Hetzner Online GmbH, DE AS24940 HETZNER-AS - Hetzner Online GmbH, DE	-

Checks

✓ 4 nameservers #6

Delegated to ns.c3d2.de, ns.spaceboyz.net, ns1.supersandro.de, ns2.zentralwerk.org.
✓ Parent and zone agree #7

The parent delegation and the zone's NS records list the same nameservers.
✓ Glue present and correct #8

Glue is published for the nameservers inside the zone: ns.c3d2.de.
✓ 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 4 IPv4 /24s and 4 IPv6 /48s.
✓ 2 autonomous systems #11

The nameservers are spread over: AS208135 (fluepke-net - Carl Fabian Luepke, DE): 2 addresses; AS24940 (HETZNER-AS - Hetzner Online GmbH, DE): 6 addresses.
✓ Nameserver names under 3 TLDs #12

Nameserver names use the TLDs .de, .net, .org.
✓ All reachable over IPv6 #13

Every nameserver has an IPv6 address.

Nameservers

warn

8 of 8 addresses answer authoritatively

Found

Nameserver	Answer	Recursion	TCP / EDNS	AXFR	Version
ns.c3d2.de 45.158.40.165	NOERROR, 17 ms, authoritative	no	yes / yes	refused	-
ns.c3d2.de 2a0f:5382:acab:1400::a5	NOERROR, 17 ms, authoritative	no	yes / yes	refused	-
ns.spaceboyz.net 37.27.116.148	NOERROR, 24 ms, authoritative	no	yes / yes	refused	-
ns.spaceboyz.net 2a01:4f9:3070:2728::4	NOERROR, 24 ms, authoritative	no	yes / yes	refused	-
ns1.supersandro.de 188.34.196.104	NOERROR, 9 ms, authoritative	no	yes / yes	refused	-
ns1.supersandro.de 2a01:4f8:1c1c:1d38::1	NOERROR, 8 ms, authoritative	no	yes / yes	refused	-
ns2.zentralwerk.org 138.201.192.243	NOERROR, 7 ms, authoritative	no	yes / yes	refused	Knot DNS 3.5.8
ns2.zentralwerk.org 2a01:4f8:172:3a90::1	NOERROR, 7 ms, authoritative	no	yes / yes	refused	Knot DNS 3.5.8

Checks

✓ All respond #14

All 8 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: ns2.zentralwerk.org: "Knot DNS 3.5.8". 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 2026101900 · primary ns.c3d2.de

Found

Primary (MNAME): ns.c3d2.de
Contact (RNAME): hostmaster.c3d2.de
Serial: 2026101900
Refresh / retry: 14400 s / 1800 s
Expire: 604800 s
Negative TTL: 600 s

Serial per nameserver

Nameserver	Serial
ns.c3d2.de (45.158.40.165)	2026101900
ns.c3d2.de (2a0f:5382:acab:1400::a5)	2026101900
ns.spaceboyz.net (37.27.116.148)	2026101900
ns.spaceboyz.net (2a01:4f9:3070:2728::4)	2026101900
ns1.supersandro.de (188.34.196.104)	2026101900
ns1.supersandro.de (2a01:4f8:1c1c:1d38::1)	2026101900
ns2.zentralwerk.org (138.201.192.243)	2026101900
ns2.zentralwerk.org (2a01:4f8:172:3a90::1)	2026101900

Checks

✓ Serial 2026101900 everywhere #22

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

SOA refresh 4h, retry 30m, expire 7d, negative TTL 10m.
✓ Primary is a public nameserver #24

The primary nameserver ns.c3d2.de is one of the listed nameservers.
✓ Contact hostmaster@c3d2.de #25

The SOA RNAME hostmaster.c3d2.de means hostmaster@c3d2.de.
✓ Date-based serial #26

The serial 2026101900 follows the YYYYMMDDnn convention (2026-10-19).

DNSSEC

info

Signed, DS published at parent

Found

Validated by resolver: yes
Denial of existence: NSEC
Signatures valid until: 2 November 2026

DS at the parent

Key tag	Algorithm	Digest	Matches a key
64309	ECDSAP256SHA256 (13)	SHA256 E3F0E5CE2B6439CA…	yes

DNSKEY in the zone

Key tag	Role	Algorithm
28585	ZSK (256)	ECDSAP256SHA256 (13)
64309	KSK (257)	ECDSAP256SHA256 (13)

Checks

✓ Signed and validated #27

The zone is signed, the parent publishes a DS record, and the resolver validates the answers.
✓ DS matches a key #28

The DS record at the parent matches a key in the zone: key tag 64309 (SHA256).
✓ Modern algorithms #29

Key algorithms: ECDSAP256SHA256 (13).
✓ Signatures valid until 2026-11-02 #30

The earliest DNSKEY/SOA signature expires at 2026-11-02 01:44 UTC.
i

NSEC

The zone uses NSEC, so its full contents can be listed by walking the NSEC chain. That is fine unless the names are sensitive.

#31

Records

pass

13 records at the apex

Found

Read from: 45.158.40.165:53

Type	Value	TTL
SOA	ns.c3d2.de. hostmaster.c3d2.de. 2026101900 14400 1800 604800 600	3600
NS	ns2.zentralwerk.org.	3600
NS	ns.c3d2.de.	3600
NS	ns.spaceboyz.net.	3600
NS	ns1.supersandro.de.	3600
A	45.158.40.167	3600
AAAA	2a0f:5382:acab:1400::a7	3600
MX	10 mail.flpk.zentralwerk.org.	3600
TXT	"v=spf1 mx -all"	3600
TXT	"google-site-verification=xGviXV4_vVwsGK2L47JWy6T7hn3OndKflzepyAYgS-Q"	3600
CAA	128 iodef "mailto:mail@c3d2.de"	3600
CAA	128 issue "letsencrypt.org"	3600
CAA	128 issuewild "letsencrypt.org"	3600

Checks

✓ TTLs within range #32

TTLs: A 1h, AAAA 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.
✓ CAA restricts issuance #35

Certificates may be issued by: letsencrypt.org.