hs-esslingen.de

Checked 21 October 2026, 22:51 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

dns1.belwue.de, dns1.hs-esslingen.de, dns3.belwue.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns1.belwue.de, dns1.hs-esslingen.de, dns3.belwue.de
NS in the zone
dns1.belwue.de, dns1.hs-esslingen.de, dns3.belwue.de
NameserverAddressesNetwork (AS)Glue
dns1.belwue.de129.143.2.10 2001:7c0::53:10AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE129.143.2.10 2001:7c0::53:10
dns1.hs-esslingen.de134.108.44.53AS553 BELWUE - Universitaet Stuttgart, DE134.108.44.53
dns3.belwue.de129.143.253.133 2001:7c0:0:253::133AS553 BELWUE - Universitaet Stuttgart, DE AS553 BELWUE - Universitaet Stuttgart, DE129.143.253.133 2001:7c0:0:253::133

Checks

  • ✓ 3 nameservers #6
    Delegated to dns1.belwue.de, dns1.hs-esslingen.de, dns3.belwue.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: dns1.hs-esslingen.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 2001:7c0::/48, while the other address family is spread over several networks.
    #10
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS553 (BELWUE - Universitaet Stuttgart, DE): 5 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
  • i
    Partly IPv6
    These nameservers have no IPv6 address: dns1.hs-esslingen.de.
    #13

Nameservers

warn

5 of 5 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns1.belwue.de 129.143.2.10NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns1.belwue.de 2001:7c0::53:10NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns1.hs-esslingen.de 134.108.44.53NOERROR, 8 ms, authoritativenoyes / yesrefused-
dns3.belwue.de 129.143.253.133NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)
dns3.belwue.de 2001:7c0:0:253::133NOERROR, 7 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)

Checks

  • ✓ All respond #14
    All 5 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: dns1.belwue.de: "PowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)"; dns3.belwue.de: "PowerDNS Authoritative Server 4.5.5 (built Dec 8 2022 18:24:18 by root@a309361b6303)". 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 2610211525 · primary dns1.hs-esslingen.de

Found

Primary (MNAME)
dns1.hs-esslingen.de
Contact (RNAME)
hostmaster.hs-esslingen.de
Serial
2610211525
Refresh / retry
18600 s / 1800 s
Expire
2419200 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
dns1.belwue.de (129.143.2.10)2610211525
dns1.belwue.de (2001:7c0::53:10)2610211525
dns1.hs-esslingen.de (134.108.44.53)2610211525
dns3.belwue.de (129.143.253.133)2610211525
dns3.belwue.de (2001:7c0:0:253::133)2610211525

Checks

  • ✓ Serial 2610211525 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 310m, retry 30m, expire 28d, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns1.hs-esslingen.de is one of the listed nameservers.
  • ✓ Contact hostmaster@hs-esslingen.de #25
    The SOA RNAME hostmaster.hs-esslingen.de means hostmaster@hs-esslingen.de.
  • ✓ Timestamp serial #26
    The serial 2610211525 is a Unix timestamp (2052-09-17 18:45 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

pass

16 records at the apex

Found

Read from
129.143.2.10:53
TypeValueTTL
SOAdns1.hs-esslingen.de. hostmaster.hs-esslingen.de. 2610211525 18600 1800 2419200 8640086400
NSdns1.BelWue.de.86400
NSdns3.BelWue.de.86400
NSdns1.hs-esslingen.de.86400
A134.108.34.386400
MX50 mx01.hs-esslingen.de.86400
TXT"MS=ms66765334"86400
TXT"MS=9333EEEF108D5213C17D05C18164311D14F78B7E"86400
TXT"cisco-ci-domain-verification=11fd5a9da1ce75fef523a255827a120d4046ad16e3d42b681d87654bb2a56cb5"86400
TXT"adobe-idp-site-verification=6167385332672b50ee9d071ccbad0f86492c775b2471bc85b1e6e3eac1e4e410"86400
TXT"v=spf1 a:mail.hs-esslingen.de a:rhlx01.hs-esslingen.de ?ip4:134.108.0.0/16 ?include:lakof-bw.de ~all"86400
TXT"academiccloud-site-verification=yn2gXRjh9QXMSPyjdMtEABF5G"86400
TXT"google-site-verification=PoWe0OcH05zg3EApw0Ygqlbu4v8dm8MRhqm5fwdFKQk"86400
CAA0 issue "harica.gr"86400
CAA0 issue "pki.dfn.de"86400
CAA0 issue "sectigo.com"86400

Checks

  • ✓ TTLs within range #32
    TTLs: A 1d, MX 1d, NS 1d.
  • ✓ 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: harica.gr, pki.dfn.de, sectigo.com.