smartsteuer.de

Checked 22 October 2026, 00:22 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

ns01.cloud.syseleven.net, ns02.cloud.syseleven.net, ns03.cloud.syseleven.net, ns04.cloud.syseleven.net

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns01.cloud.syseleven.net, ns02.cloud.syseleven.net, ns03.cloud.syseleven.net, ns04.cloud.syseleven.net
NS in the zone
ns01.cloud.syseleven.net, ns02.cloud.syseleven.net, ns03.cloud.syseleven.net, ns04.cloud.syseleven.net
NameserverAddressesNetwork (AS)Glue
ns01.cloud.syseleven.net37.123.106.230 2a00:13c8:1337:10::AS25291 SYSELEVEN - SysEleven GmbH, DE AS25291 SYSELEVEN - SysEleven GmbH, DE-
ns02.cloud.syseleven.net151.252.46.48 2a00:13c8:1337:32::AS25291 SYSELEVEN - SysEleven GmbH, DE AS25291 SYSELEVEN - SysEleven GmbH, DE-
ns03.cloud.syseleven.net77.247.83.64 2a04:d480:2c00:5::1AS25291 SYSELEVEN - SysEleven GmbH, DE AS25291 SYSELEVEN - SysEleven GmbH, DE-
ns04.cloud.syseleven.net37.123.106.68 2a04:d480:4400:1::4AS25291 SYSELEVEN - SysEleven GmbH, DE AS25291 SYSELEVEN - SysEleven GmbH, DE-

Checks

  • ✓ 4 nameservers #6
    Delegated to ns01.cloud.syseleven.net, ns02.cloud.syseleven.net, ns03.cloud.syseleven.net, ns04.cloud.syseleven.net.
  • ✓ 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 3 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS25291 (SYSELEVEN - SysEleven GmbH, DE): 8 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 .net
    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

pass

8 of 8 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns01.cloud.syseleven.net 37.123.106.230NOERROR, 20 ms, authoritativenoyes / yesrefused-
ns01.cloud.syseleven.net 2a00:13c8:1337:10::NOERROR, 21 ms, authoritativenoyes / yesrefused-
ns02.cloud.syseleven.net 151.252.46.48NOERROR, 12 ms, authoritativenoyes / yesrefused-
ns02.cloud.syseleven.net 2a00:13c8:1337:32::NOERROR, 17 ms, authoritativenoyes / yesrefused-
ns03.cloud.syseleven.net 77.247.83.64NOERROR, 11 ms, authoritativenoyes / yesrefused-
ns03.cloud.syseleven.net 2a04:d480:2c00:5::1NOERROR, 19 ms, authoritativenoyes / yesrefused-
ns04.cloud.syseleven.net 37.123.106.68NOERROR, 10 ms, authoritativenoyes / yesrefused-
ns04.cloud.syseleven.net 2a04:d480:4400:1::4NOERROR, 11 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.
  • ✓ No version disclosed #17
    The nameservers don't reveal their software version.
  • ✓ 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 1792539198 · primary ns04.cloud.syseleven.net

Found

Primary (MNAME)
ns04.cloud.syseleven.net
Contact (RNAME)
devops.smartsteuer.de
Serial
1792539198
Refresh / retry
21600 s / 3600 s
Expire
259200 s
Negative TTL
300 s

Serial per nameserver

NameserverSerial
ns01.cloud.syseleven.net (37.123.106.230)1792539198
ns01.cloud.syseleven.net (2a00:13c8:1337:10::)1792539198
ns02.cloud.syseleven.net (151.252.46.48)1792539198
ns02.cloud.syseleven.net (2a00:13c8:1337:32::)1792539198
ns03.cloud.syseleven.net (77.247.83.64)1792539198
ns03.cloud.syseleven.net (2a04:d480:2c00:5::1)1792539198
ns04.cloud.syseleven.net (37.123.106.68)1792539198
ns04.cloud.syseleven.net (2a04:d480:4400:1::4)1792539198

Checks

  • ✓ Serial 1792539198 everywhere #22
    All nameservers serve the same version of the zone.
  • !
    Unusual SOA timers
    expire 3d is shorter than 7d; secondaries stop answering too soon when the primary is down. Current values: refresh 6h, retry 1h, expire 3d, negative TTL 5m.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns04.cloud.syseleven.net is one of the listed nameservers.
  • ✓ Contact devops@smartsteuer.de #25
    The SOA RNAME devops.smartsteuer.de means devops@smartsteuer.de.
  • ✓ Timestamp serial #26
    The serial 1792539198 is a Unix timestamp (2026-10-20 23:33 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
37.123.106.230:53
TypeValueTTL
SOAns04.cloud.syseleven.net. devops.smartsteuer.de. 1792539198 21600 3600 259200 3003000
NSns01.cloud.syseleven.net.3000
NSns02.cloud.syseleven.net.3000
NSns03.cloud.syseleven.net.3000
NSns04.cloud.syseleven.net.3000
A77.247.82.119300
MX30 mail3.haufe.de.300
MX20 mail2.haufe.de.300
MX10 mail.haufe.de.300
TXT"google-site-verification=v0ByTWT_dC3KkEkUY5edkxu6_EOsu55eCVjBJ58CM38"300
TXT"google-site-verification=WI8dVCOsP0neo6v9u_7G1ReYEo8_02wsCjPP0K_Tt5E"300
TXT"v=spf1 mx a include:spf.mailjet.com include:spf.protection.outlook.com include:spf.de.cancom-mase.com ip4:91.250.66.245 ip4:80.237.138.0/24 ip6:2a01:488:42::/48 include:amazonses.com include:spf.brevo.com -all"300
TXT"brevo-code:fbcd1e65af3fe9aafd398a274f21ecda"300
TXT"swisssign-check=_1RvC_uFVV3cMYgO3Fqk-u0zjbI"300
TXT"domainsecurity-verification=7f683fb995eefd4416a86b2b66a255cd35434f9a"300

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, MX 5m, NS 50m. The NS TTL at the parent is 1d and in the zone 50m; resolvers may use either.
  • ✓ No CNAME at the apex #33
    The zone apex has no CNAME record.
  • i
    Wildcard record
    A random name under the zone resolves, so there is a wildcard (*) record. Typos and non-existent hosts resolve too, which can confuse mail and certificate checks.
    #34
  • 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