ukaachen.de

Checked 22 October 2026, 00:50 UTC · via 8.8.8.8
!Passed with warnings
24 passed 1 warning 0 failed 4 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-1.dfn.de, dns-2.dfn.de, zs1.rz.rwth-aachen.de, zs2.rz.rwth-aachen.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
dns-1.dfn.de, dns-2.dfn.de, zs1.rz.rwth-aachen.de, zs2.rz.rwth-aachen.de
NS in the zone
dns-1.dfn.de, dns-2.dfn.de, zs1.rz.rwth-aachen.de, zs2.rz.rwth-aachen.de
NameserverAddressesNetwork (AS)Glue
dns-1.dfn.de193.174.75.50 2001:638:d:b101::1AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE AS680 DFN - Verein zur Foerderung eines Deutschen Forschungsnetzes e.V., DE-
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-
zs1.rz.rwth-aachen.de134.130.4.9 2a00:8a60:0:4::9AS47610 RWTH-AS - RWTH Aachen University, DE AS47610 RWTH-AS - RWTH Aachen University, DE134.130.4.9 2a00:8a60:0:4::9
zs2.rz.rwth-aachen.de134.130.5.9 2a00:8a60:0:5::9AS47610 RWTH-AS - RWTH Aachen University, DE AS47610 RWTH-AS - RWTH Aachen University, DE134.130.5.9 2a00:8a60:0:5::9

Checks

  • ✓ 4 nameservers #6
    Delegated to dns-1.dfn.de, dns-2.dfn.de, zs1.rz.rwth-aachen.de, zs2.rz.rwth-aachen.de.
  • ✓ 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 different networks #10
    The nameservers are spread over 3 IPv4 /24s and 2 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS47610 (RWTH-AS - RWTH Aachen University, DE): 4 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
  • ✓ All reachable over IPv6 #13
    Every nameserver has an IPv6 address.

Nameservers

info

8 of 8 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns-1.dfn.de 193.174.75.50NOERROR, 12 ms, authoritativenoyes / yesrefused0
dns-1.dfn.de 2001:638:d:b101::1NOERROR, 14 ms, authoritativenoyes / yesrefused0
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
zs1.rz.rwth-aachen.de 134.130.4.9NOERROR, 7 ms, authoritativenoyes / yesrefused-
zs1.rz.rwth-aachen.de 2a00:8a60:0:4::9NOERROR, 7 ms, authoritativenoyes / yesrefused-
zs2.rz.rwth-aachen.de 134.130.5.9NOERROR, 7 ms, authoritativenoyes / yesrefused-
zs2.rz.rwth-aachen.de 2a00:8a60:0:5::9NOERROR, 8 ms, authoritativenoyes / yesrefused-

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.
  • i
    Identifying string disclosed
    These nameservers answer version queries with a string that is not a version number: dns-1.dfn.de: "0"; dns-2.dfn.de: "0".
    #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 2026093001 · primary zs1.rz.rwth-aachen.de

Found

Primary (MNAME)
zs1.rz.rwth-aachen.de
Contact (RNAME)
hostmaster.rwth-aachen.de
Serial
2026093001
Refresh / retry
10800 s / 3600 s
Expire
3600000 s
Negative TTL
600 s

Serial per nameserver

NameserverSerial
dns-1.dfn.de (193.174.75.50)2026093001
dns-1.dfn.de (2001:638:d:b101::1)2026093001
dns-2.dfn.de (193.174.75.54)2026093001
dns-2.dfn.de (2001:638:d:b102::1)2026093001
zs1.rz.rwth-aachen.de (134.130.4.9)2026093001
zs1.rz.rwth-aachen.de (2a00:8a60:0:4::9)2026093001
zs2.rz.rwth-aachen.de (134.130.5.9)2026093001
zs2.rz.rwth-aachen.de (2a00:8a60:0:5::9)2026093001

Checks

  • ✓ Serial 2026093001 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 1000h, negative TTL 10m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver zs1.rz.rwth-aachen.de is one of the listed nameservers.
  • ✓ Contact hostmaster@rwth-aachen.de #25
    The SOA RNAME hostmaster.rwth-aachen.de means hostmaster@rwth-aachen.de.
  • ✓ Date-based serial #26
    The serial 2026093001 follows the YYYYMMDDnn convention (2026-09-30).

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
193.174.75.50:53
TypeValueTTL
SOAzs1.rz.rwth-aachen.de. hostmaster.rwth-aachen.de. 2026093001 10800 3600 3600000 60086400
NSdns-2.dfn.de.86400
NSdns-1.dfn.de.86400
NSzs1.rz.rwth-aachen.de.86400
NSzs2.rz.rwth-aachen.de.86400
A134.130.15.16086400
MX4422 ukaachen-de.mail.protection.outlook.com.86400
TXT"MS=ms17802702"86400
TXT"apple-domain-verification=41HGEbzK4ciMlX5o"86400
TXT"EBnDhTlufM2uvS3he34EdKYf0oHfQgZqFFqYtQTBShGnrjbJnOwXn+RxHyp30ws9IGCSajRl9atYkghpaWSH8w=="86400
TXT"v=spf1 ip4:134.130.5.32/27 ip4:134.130.5.176/28 ip6:2a00:8a60:1:e501::/64 ip6:2a00:8a60:1:e502::/64 include:spf.protection.outlook.com include:spf.crsend.com -all"86400
CAA0 issue "letsencrypt.org"86400
CAA0 issuewild ";"86400
CAA0 issue "harica.gr"86400
CAA0 iodef "mailto:ca@rwth-aachen.de"86400
CAA0 issuemail "harica.gr"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: letsencrypt.org, none (issuance forbidden), harica.gr.