uni-bayreuth.de

Checked 22 October 2026, 00:50 UTC · via 8.8.8.8
✗Problems found
21 passed 2 warnings 1 failed 5 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

btr0x4.rz.uni-bayreuth.de, btr0x5.rz.uni-bayreuth.de, deneb.dfn.de, dns-3.dfn.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
btr0x4.rz.uni-bayreuth.de, btr0x5.rz.uni-bayreuth.de, deneb.dfn.de, dns-3.dfn.de
NS in the zone
btr0x4.rz.uni-bayreuth.de, btr0x5.rz.uni-bayreuth.de, deneb.dfn.de, dns-3.dfn.de
NameserverAddressesNetwork (AS)Glue
btr0x4.rz.uni-bayreuth.de132.180.15.4AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE132.180.15.4
btr0x5.rz.uni-bayreuth.de132.180.15.5AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE132.180.15.5
deneb.dfn.de192.76.176.9 2001:638:800:1::9AS680 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-

Checks

  • ✓ 4 nameservers #6
    Delegated to btr0x4.rz.uni-bayreuth.de, btr0x5.rz.uni-bayreuth.de, deneb.dfn.de, dns-3.dfn.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: btr0x4.rz.uni-bayreuth.de, btr0x5.rz.uni-bayreuth.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 3 IPv4 /24s and 2 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS680 (DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE): 6 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: btr0x4.rz.uni-bayreuth.de, btr0x5.rz.uni-bayreuth.de.
    #13

Nameservers

fail

5 of 6 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
btr0x4.rz.uni-bayreuth.de 132.180.15.4no responsenono / no--
btr0x5.rz.uni-bayreuth.de 132.180.15.5NOERROR, 9 ms, authoritativenoyes / yesrefused9.5.0-P2
deneb.dfn.de 192.76.176.9NOERROR, 14 ms, authoritativenoyes / yesrefused0
deneb.dfn.de 2001:638:800:1::9NOERROR, 14 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

Checks

  • ✗
    Nameservers not responding
    These addresses did not answer, so resolvers waste time on timeouts: btr0x4.rz.uni-bayreuth.de (132.180.15.4): read udp 46.225.38.91:37208->132.180.15.4:53: i/o timeout.
    #14
  • ✓ 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: btr0x5.rz.uni-bayreuth.de: "9.5.0-P2". 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 2026102100 · primary btr0x5.rz.uni-bayreuth.de

Found

Primary (MNAME)
btr0x5.rz.uni-bayreuth.de
Contact (RNAME)
postmaster.uni-bayreuth.de
Serial
2026102100
Refresh / retry
18000 s / 1800 s
Expire
3600000 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
btr0x5.rz.uni-bayreuth.de (132.180.15.5)2026102100
deneb.dfn.de (192.76.176.9)2026102100
deneb.dfn.de (2001:638:800:1::9)2026102100
dns-3.dfn.de (193.174.75.58)2026102100
dns-3.dfn.de (2001:638:d:b103::1)2026102100

Checks

  • ✓ Serial 2026102100 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 5h, retry 30m, expire 1000h, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver btr0x5.rz.uni-bayreuth.de is one of the listed nameservers.
  • ✓ Contact postmaster@uni-bayreuth.de #25
    The SOA RNAME postmaster.uni-bayreuth.de means postmaster@uni-bayreuth.de.
  • ✓ Date-based serial #26
    The serial 2026102100 follows the YYYYMMDDnn convention (2026-10-21).

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

23 records at the apex

Found

Read from
132.180.15.5:53
TypeValueTTL
SOAbtr0x5.rz.uni-bayreuth.de. postmaster.uni-bayreuth.de. 2026102100 18000 1800 3600000 86400300
NSbtr0x4.rz.uni-bayreuth.de.300
NSbtr0x5.rz.uni-bayreuth.de.300
NSdeneb.dfn.de.300
NSdns-3.dfn.de.300
A132.180.6.8300
MX10 mailgate-smtp1.uni-bayreuth.de.300
MX11 mailgate-smtp1.uni-bayreuth.de.300
TXT"academiccloud-site-verification=QJYXDSqw3mEjZ7YhpnWHR6RSS"300
TXT"google-site-verification=MuaEPRdxXVkbAbR-4oIsM1F46mRIf4W4KNARFzl7HOk"300
TXT"google-site-verification=mdvlJpHhmbTLrVRbHWAJeNG5v93K8iDmvRMtL_-cQbE"300
TXT"v309Bf7yEsr8UjZiCv5ddM+b+WpqRllgxWvhn3eJltryymDLUvQ6sV36t5mAUnOX4+Kkqjjva/Ust0BtmxHn9g=="300
TXT"adobe-idp-site-verification=428687cc264ed8d17024b0454acb417f8f38b7ae10760ea416f1f7c7e08970cf"300
TXT"dell-technologies-domain-verification=uni-bayreuth.de_85f64cfd-a4d3-4e8f-b3a4-7deae021b4c9_1720258546"300
TXT"v=spf1 mx ip4:132.180.16.228 ip4:132.180.16.213 ip4:132.180.16.214 ip4:132.180.16.216 ip4:132.180.16.212 ip4:132.180.16.211 mx:mailgate01.myubt.de mx:mailgate02.myubt.de -all"300
TXT"MS=ms44328619"300
TXT"HARICA-hpkeTXGTcsa9Q6bnjbK"300
TXT"apple-domain-verification=HMZVmKEk68fQrgvB"300
TXT"autodesk-domain-verification=fZAx1yt86mwGTSQKnlBw"300
CAA0 issue "harica.gr"300
CAA0 issue "pki.dfn.de"300
CAA0 issue "sectigo.com"300
CAA0 iodef "mailto:Johannes.Foerster@uni-bayreuth.de"300

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, MX 5m, NS 5m. The NS TTL at the parent is 1d and in the zone 5m; 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: harica.gr, pki.dfn.de, sectigo.com.