gsi.de

Checked 21 October 2026, 22:41 UTC · via 8.8.8.8
!Passed with warnings
21 passed 2 warnings 0 failed 6 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

info

dns-2.dfn.de, dns-3.dfn.de, lxdns1.gsi.de, lxdns2.gsi.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-2.dfn.de, dns-3.dfn.de, lxdns1.gsi.de, lxdns2.gsi.de
NS in the zone
dns-2.dfn.de, dns-3.dfn.de, lxdns1.gsi.de, lxdns2.gsi.de
NameserverAddressesNetwork (AS)Glue
dns-2.dfn.de193.174.75.54 2001:638:d:b102::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
dns-3.dfn.de193.174.75.58 2001:638:d:b103::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
lxdns1.gsi.de140.181.96.11AS209499 GSI - GSI Helmholtzzentrum fur Schwerionenforschung GmbH, DE140.181.96.11
lxdns2.gsi.de140.181.96.29AS209499 GSI - GSI Helmholtzzentrum fur Schwerionenforschung GmbH, DE140.181.96.29

Checks

  • ✓ 4 nameservers #6
    Delegated to dns-2.dfn.de, dns-3.dfn.de, lxdns1.gsi.de, lxdns2.gsi.de.
  • ✓ 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: lxdns1.gsi.de, lxdns2.gsi.de.
  • ✓ All names resolve #9
    Every nameserver name has an address and is not an alias.
  • i
    One address family in one network
    all IPv6 addresses are in 2001:638:d::/48, while the other address family is spread over several networks.
    #10
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS209499 (GSI - GSI Helmholtzzentrum fur Schwerionenforschung GmbH, DE): 2 addresses; AS680 (DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE): 4 addresses.
  • 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
  • i
    Partly IPv6
    These nameservers have no IPv6 address: lxdns1.gsi.de, lxdns2.gsi.de.
    #13

Nameservers

warn

6 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns-2.dfn.de 193.174.75.54NOERROR, 6 ms, authoritativenoyes / yesrefused0
dns-2.dfn.de 2001:638:d:b102::1NOERROR, 7 ms, authoritativenoyes / yesrefused0
dns-3.dfn.de 193.174.75.58NOERROR, 10 ms, authoritativenoyes / yesrefused0
dns-3.dfn.de 2001:638:d:b103::1NOERROR, 8 ms, authoritativenoyes / yesrefused0
lxdns1.gsi.de 140.181.96.11NOERROR, 12 ms, authoritativenoyes / yesrefused9.11.37-0~deb10u1~deb9u1-Debian
lxdns2.gsi.de 140.181.96.29NOERROR, 13 ms, authoritativenoyes / yesrefused9.11.37-0~deb10u1~deb9u1-Debian

Checks

  • ✓ All respond #14
    All 6 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: lxdns1.gsi.de: "9.11.37-0~deb10u1~deb9u1-Debian"; lxdns2.gsi.de: "9.11.37-0~deb10u1~deb9u1-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 1792588040 · primary lxdns1.gsi.de

Found

Primary (MNAME)
lxdns1.gsi.de
Contact (RNAME)
linux-service.gsi.de
Serial
1792588040
Refresh / retry
10800 s / 3600 s
Expire
604800 s
Negative TTL
900 s

Serial per nameserver

NameserverSerial
dns-2.dfn.de (193.174.75.54)1792588040
dns-2.dfn.de (2001:638:d:b102::1)1792588040
dns-3.dfn.de (193.174.75.58)1792588040
dns-3.dfn.de (2001:638:d:b103::1)1792588040
lxdns1.gsi.de (140.181.96.11)1792588040
lxdns2.gsi.de (140.181.96.29)1792588040

Checks

  • ✓ Serial 1792588040 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 7d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver lxdns1.gsi.de is one of the listed nameservers.
  • ✓ Contact linux-service@gsi.de #25
    The SOA RNAME linux-service.gsi.de means linux-service@gsi.de.
  • ✓ Timestamp serial #26
    The serial 1792588040 is a Unix timestamp (2026-10-21 13:07 UTC).

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

15 records at the apex

Found

Read from
193.174.75.54:53
TypeValueTTL
SOAlxdns1.gsi.de. linux-service.gsi.de. 1792588040 10800 3600 604800 90010800
NSlxdns2.gsi.de.10800
NSlxdns1.gsi.de.10800
NSdns-2.dfn.de.10800
NSdns-3.dfn.de.10800
A140.181.3.149500
MX10 a2841.mx.srv.dfn.de.900
MX10 b2841.mx.srv.dfn.de.900
MX10 c2841.mx.srv.dfn.de.900
TXT"MS=ms38604205"10800
TXT"google-site-verification=dbjLrVX1_-lOC8CzUtYiv_Nu0ZDCkceGTM2DjWqtM2A"10800
TXT"OSSRH-49122"10800
TXT"atlassian-domain-verification=A941Bimy05RkQFmpa86uHO6XmZJyA8vfEETBM84NjcdVbusTMIo76DJcZWN3aGOd"10800
TXT"v=spf1 ip4:140.181.3.111 ip4:140.181.3.112 ip4:140.181.3.146 ip4:140.181.3.147 ip4:140.181.3.30 ip4:140.181.3.230 ip4:140.181.3.140 ip4:140.181.3.141 include:spf.protection.outlook.com ~all"10800
TXT"ZOOM_verify_vKYDVKEQQA27XaZvbX2t1Q"10800

Checks

  • ✓ TTLs within range #32
    TTLs: A 8m20s, MX 15m, NS 3h. The NS TTL at the parent is 1d and in the zone 3h; 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