sr.de

Checked 22 October 2026, 00:30 UTC · via 8.8.8.8
!Passed with warnings
21 passed 3 warnings 0 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

warn

ns01.sr.sybcom.net, ns02.sr.sybcom.net, ns03.sr.sybcom.net

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns01.sr.sybcom.net, ns02.sr.sybcom.net, ns03.sr.sybcom.net
NS in the zone
ns01.sr.sybcom.net, ns02.sr.sybcom.net, ns03.sr.sybcom.net
NameserverAddressesNetwork (AS)Glue
ns01.sr.sybcom.net213.147.3.9AS12431 SYB-AS - SYBCOM GmbH, DE-
ns02.sr.sybcom.net213.147.5.9AS12431 SYB-AS - SYBCOM GmbH, DE-
ns03.sr.sybcom.net213.147.14.9AS12431 SYB-AS - SYBCOM GmbH, DE-

Checks

  • ✓ 3 nameservers #6
    Delegated to ns01.sr.sybcom.net, ns02.sr.sybcom.net, ns03.sr.sybcom.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 0 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS12431 (SYB-AS - SYBCOM GmbH, DE): 3 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
  • !
    No IPv6
    None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.
    #13

Nameservers

warn

3 of 3 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns01.sr.sybcom.net 213.147.3.9NOERROR, 8 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.7.3
ns02.sr.sybcom.net 213.147.5.9NOERROR, 9 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.7.3
ns03.sr.sybcom.net 213.147.14.9NOERROR, 9 ms, authoritativenoyes / yesrefusedPowerDNS Authoritative Server 4.7.3

Checks

  • ✓ All respond #14
    All 3 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: ns01.sr.sybcom.net: "PowerDNS Authoritative Server 4.7.3"; ns02.sr.sybcom.net: "PowerDNS Authoritative Server 4.7.3"; ns03.sr.sybcom.net: "PowerDNS Authoritative Server 4.7.3". 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 2026100501 · primary ns01.sr.sybcom.net

Found

Primary (MNAME)
ns01.sr.sybcom.net
Contact (RNAME)
dns.sybcom.de
Serial
2026100501
Refresh / retry
28800 s / 7200 s
Expire
3600000 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
ns01.sr.sybcom.net (213.147.3.9)2026100501
ns02.sr.sybcom.net (213.147.5.9)2026100501
ns03.sr.sybcom.net (213.147.14.9)2026100501

Checks

  • ✓ Serial 2026100501 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 8h, retry 2h, expire 1000h, negative TTL 1d.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns01.sr.sybcom.net is one of the listed nameservers.
  • ✓ Contact dns@sybcom.de #25
    The SOA RNAME dns.sybcom.de means dns@sybcom.de.
  • ✓ Date-based serial #26
    The serial 2026100501 follows the YYYYMMDDnn convention (2026-10-05).

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

17 records at the apex

Found

Read from
213.147.3.9:53
TypeValueTTL
SOAns01.sr.sybcom.net. dns.sybcom.de. 2026100501 28800 7200 3600000 86400300
NSns03.sr.sybcom.net.300
NSns02.sr.sybcom.net.300
NSns01.sr.sybcom.net.300
A185.25.96.80300
A185.25.96.77300
A185.25.96.78300
A185.25.96.79300
MX16 sr-de.mail.protection.outlook.com.300
MX18 lavgateway3.sr-online.de.300
TXT"google-site-verification=BBX9wUqS1yKsC6PRUEf922llGK0RQdNu2jminyeX-B4"300
TXT"facebook-domain-verification=9ohsxvp3gqpydfq2clsztlidd4l077."300
TXT"MS=ms67546361"300
TXT"apple-domain-verification=wym8Yqq9DIBwob4g"300
TXT"google-site-verification=76bEgkC6d5ypfFKxKyf7qUKvEKszHynYFfcl1GlFWMk"300
TXT"v=spf1 include:spf.protection.outlook.com include:spf.mailjet.com ip4:185.25.97.0/24 ip4:185.25.96.0/24 ip4:213.147.7.0/24 ip4:213.147.6.0/24 ip4:62.55.182.68 ip4:185.25.99.0/24 ~all"300
TXT"r47nrr99fbhm2dtw7rlmw9wdn4dyl7k0"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.
  • 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