schweitzer-online.de

Checked 22 October 2026, 00:02 UTC · via 8.8.8.8
!Passed with warnings
22 passed 3 warnings 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

nsa9.schlundtech.de, nsb9.schlundtech.de, nsc9.schlundtech.de, nsd9.schlundtech.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
nsa9.schlundtech.de, nsb9.schlundtech.de, nsc9.schlundtech.de, nsd9.schlundtech.de
NS in the zone
nsa9.schlundtech.de, nsb9.schlundtech.de, nsc9.schlundtech.de, nsd9.schlundtech.de
NameserverAddressesNetwork (AS)Glue
nsa9.schlundtech.de185.132.34.227 2607:f1c0:fe:53:185:132:34:227AS15418 IONOS-ANYCAST - Fasthosts Internet Limited, GB AS15418 IONOS-ANYCAST - Fasthosts Internet Limited, GB-
nsb9.schlundtech.de185.132.35.227 2607:f1c0:fe:53:185:132:35:227AS15418 IONOS-ANYCAST - Fasthosts Internet Limited, GB AS15418 IONOS-ANYCAST - Fasthosts Internet Limited, GB-
nsc9.schlundtech.de217.160.80.227 2001:8d8:fe:53:217:160:80:227AS8560 IONOS-AS - IONOS SE, DE AS8560 IONOS-AS - IONOS SE, DE-
nsd9.schlundtech.de217.160.81.227 2001:8d8:fe:53:217:160:81:227AS8560 IONOS-AS - IONOS SE, DE AS8560 IONOS-AS - IONOS SE, DE-

Checks

  • ✓ 4 nameservers #6
    Delegated to nsa9.schlundtech.de, nsb9.schlundtech.de, nsc9.schlundtech.de, nsd9.schlundtech.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 4 IPv4 /24s and 2 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS15418 (IONOS-ANYCAST - Fasthosts Internet Limited, GB): 4 addresses; AS8560 (IONOS-AS - IONOS SE, 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
nsa9.schlundtech.de 185.132.34.227NOERROR, 4 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/
nsa9.schlundtech.de 2607:f1c0:fe:53:185:132:34:227NOERROR, 4 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/
nsb9.schlundtech.de 185.132.35.227NOERROR, 3 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/
nsb9.schlundtech.de 2607:f1c0:fe:53:185:132:35:227NOERROR, 3 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/
nsc9.schlundtech.de 217.160.80.227NOERROR, 9 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/
nsc9.schlundtech.de 2001:8d8:fe:53:217:160:80:227NOERROR, 9 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/
nsd9.schlundtech.de 217.160.81.227NOERROR, 9 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/
nsd9.schlundtech.de 2001:8d8:fe:53:217:160:81:227NOERROR, 9 ms, authoritativenoyes / yesrefusedServed by PowerDNS - https://www.powerdns.com/

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: nsa9.schlundtech.de: "Served by PowerDNS - https://www.powerdns.com/"; nsb9.schlundtech.de: "Served by PowerDNS - https://www.powerdns.com/"; nsc9.schlundtech.de: "Served by PowerDNS - https://www.powerdns.com/"; nsd9.schlundtech.de: "Served by PowerDNS - https://www.powerdns.com/".
    #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

warn

serial 2025111336 · primary nsa9.schlundtech.de

Found

Primary (MNAME)
nsa9.schlundtech.de
Contact (RNAME)
do-not-reply.schweitzer-online.de
Serial
2025111336
Refresh / retry
3600 s / 3600 s
Expire
604800 s
Negative TTL
600 s

Serial per nameserver

NameserverSerial
nsa9.schlundtech.de (185.132.34.227)2025111336
nsa9.schlundtech.de (2607:f1c0:fe:53:185:132:34:227)2025111336
nsb9.schlundtech.de (185.132.35.227)2025111336
nsb9.schlundtech.de (2607:f1c0:fe:53:185:132:35:227)2025111336
nsc9.schlundtech.de (217.160.80.227)2025111336
nsc9.schlundtech.de (2001:8d8:fe:53:217:160:80:227)2025111336
nsd9.schlundtech.de (217.160.81.227)2025111336
nsd9.schlundtech.de (2001:8d8:fe:53:217:160:81:227)2025111336

Checks

  • ✓ Serial 2025111336 everywhere #22
    All nameservers serve the same version of the zone.
  • !
    Unusual SOA timers
    retry 1h should be shorter than refresh 1h. Current values: refresh 1h, retry 1h, expire 7d, negative TTL 10m.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver nsa9.schlundtech.de is one of the listed nameservers.
  • ✓ Contact do-not-reply@schweitzer-online.de #25
    The SOA RNAME do-not-reply.schweitzer-online.de means do-not-reply@schweitzer-online.de.
  • ✓ Date-based serial #26
    The serial 2025111336 follows the YYYYMMDDnn convention (2025-11-13).

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

warn

21 records at the apex

Found

Read from
185.132.34.227:53
TypeValueTTL
SOAnsa9.schlundtech.de. do-not-reply.schweitzer-online.de. 2025111336 3600 3600 604800 600600
NSnsb9.schlundtech.de.600
NSnsc9.schlundtech.de.600
NSnsd9.schlundtech.de.600
NSnsa9.schlundtech.de.600
A195.162.31.55600
MX10 schweitzeronline-de02e.mail.protection.outlook.com.60
TXT"ppe-9d00752d2a462939fec5de2c116051ed89f826f83600"60
TXT"zone-ownership-verification-77e4e1a2c4cdab82a05755bfcf4754b621f0439cad51bf022854fc53d51112b1"60
TXT"v=spf1 mx ip4:195.162.30.8 ip4:195.162.31.31 ip6:2a00:15e4:5f1:de::31 include:inxserver.com include:spf.protection.outlook.com -all"60
TXT"BsLWLOuwiZP+KjYaf64CgoAHqjtyMcd+HJ0rLHQISN5cy4m5GIo/yQVf/DW1hNcuJTwrcyzNkZWNIYjjzPVszw=="60
TXT"ZOOM_verify_jV-rtlbQQWub3vp_4ib5OA"60
TXT"facebook-domain-verification=4ndaizvi57jxo9i82f65b2axw4tdce"60
TXT"2ZqTemmnPuL1RO2zEglUm6iHAPaNZEEr4ktVlC1Zzt9qzEOx47BnpneFxk+QXtSnK2HTFlJLzWrYqxHBBJ2HCg=="60
TXT"atlassian-domain-verification=OnQ0hLzDQPJdHCW2Y54rrlPEqem2JEMN/R101ajEdSxPbNcsf5QEbdxL4X9qDESQ"60
TXT"knowbe4-site-verification=662f755aa8adf828263905db010a1ecf"60
TXT"MS=ms91533742"60
CAA0 issue "digicert.com"60
CAA0 issuewild "sectigo.com"60
CAA0 issue "sectigo.com"60
CAA0 issuewild "digicert.com"60

Checks

  • !
    Very low TTLs
    These records have a TTL below 5m, causing extra queries and slower lookups: MX (1m). Low TTLs are useful just before a planned change. The NS TTL at the parent is 1d and in the zone 10m; resolvers may use either.
    #32
  • ✓ 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: digicert.com, sectigo.com.