o2online.de

Checked 21 October 2026, 23:40 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

warn

ns1.o2online.de, ns2.o2online.de, ns3.o2online.de

Found

Parent zone
de
Delegation from
a.nic.de (194.0.0.53)
NS at the parent
ns1.o2online.de, ns2.o2online.de, ns3.o2online.de
NS in the zone
ns1.o2online.de, ns2.o2online.de, ns3.o2online.de
NameserverAddressesNetwork (AS)Glue
ns1.o2online.de82.113.113.132AS6805 TDDE-ASN1 - Telefonica Germany GmbH & Co.OHG, DE82.113.113.132
ns2.o2online.de82.113.113.150AS6805 TDDE-ASN1 - Telefonica Germany GmbH & Co.OHG, DE82.113.113.150
ns3.o2online.de213.20.248.180AS6805 TDDE-ASN1 - Telefonica Germany GmbH & Co.OHG, DE213.20.248.180

Checks

  • ✓ 3 nameservers #6
    Delegated to ns1.o2online.de, ns2.o2online.de, ns3.o2online.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: ns1.o2online.de, ns2.o2online.de, ns3.o2online.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 2 IPv4 /24s and 0 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS6805 (TDDE-ASN1 - Telefonica Germany GmbH & Co.OHG, 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 .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
  • !
    No IPv6
    None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.
    #13

Nameservers

info

3 of 3 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns1.o2online.de 82.113.113.132NOERROR, 6 ms, authoritativenoyes / yesrefusedany
ns2.o2online.de 82.113.113.150NOERROR, 6 ms, authoritativenoyes / yesrefusedany
ns3.o2online.de 213.20.248.180NOERROR, 6 ms, authoritativenoyes / yesrefusedany

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.
  • i
    Identifying string disclosed
    These nameservers answer version queries with a string that is not a version number: ns1.o2online.de: "any"; ns2.o2online.de: "any"; ns3.o2online.de: "any".
    #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 2026101400 · primary ns1.o2online.de

Found

Primary (MNAME)
ns1.o2online.de
Contact (RNAME)
domain-de.telefonica.com
Serial
2026101400
Refresh / retry
10800 s / 3600 s
Expire
604800 s
Negative TTL
600 s

Serial per nameserver

NameserverSerial
ns1.o2online.de (82.113.113.132)2026101400
ns2.o2online.de (82.113.113.150)2026101400
ns3.o2online.de (213.20.248.180)2026101400

Checks

  • ✓ Serial 2026101400 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 7d, negative TTL 10m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.o2online.de is one of the listed nameservers.
  • ✓ Contact domain-de@telefonica.com #25
    The SOA RNAME domain-de.telefonica.com means domain-de@telefonica.com.
  • ✓ Date-based serial #26
    The serial 2026101400 follows the YYYYMMDDnn convention (2026-10-14).

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

21 records at the apex

Found

Read from
82.113.113.132:53
TypeValueTTL
SOAns1.o2online.de. domain-de.telefonica.com. 2026101400 10800 3600 604800 6007200
NSns1.o2online.de.7200
NSns2.o2online.de.7200
NSns3.o2online.de.7200
A141.101.90.38600
A141.101.90.39600
AAAA2a06:98c1:3200::120:0:501600
AAAA2a06:98c1:3200::120:0:500600
MX100 mx2c52.megamailservers.eu.600
MX10 mx.o2online.de.600
MX110 mx3c52.megamailservers.eu.600
MX120 mx4c52.megamailservers.eu.600
TXT"google-site-verification=7ZDGs63vaE7yemWciLcyS6TXixCaWiRv_PxkTr1Bok0"3600
TXT"facebook-domain-verification=w9pmyg2ovroz7fvkbajxsxujzd1j6k"3600
TXT"google-site-verification=ilvQrILe7LToYDt98i1gjYtEVjrTSGEiJfR3BV57vew"3600
TXT"v=spf1 ip4:82.113.101.0/24 ip4:212.23.125.184 ip4:46.28.184.125 include:spf.mail.telefonica.de include:spfc50.megamailservers.eu include:spf.mailjet.com -all"3600
TXT"wbjqxm9pt6krs013g6k3h6v6xwn6x3tz"3600
TXT"google-site-verification: ub0a6_20S3EL-pUtqn2PIRG0MOA1TWO4SQijgY0nIAQ"3600
TXT"trustpilot-one-time-verification-id=d7d7e916-a052-417e-99f2-62715f9e892a"3600
TXT"_ndmcvxtiy3e4khz4kjr31phy9ii0r64"3600
TXT"google-site-verification=FwT3kAVc80VnzKG5neMQDZQBnAAzXqUQ1JFqgkQUk9c"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 10m, AAAA 10m, MX 10m, NS 2h. The NS TTL at the parent is 1d and in the zone 2h; 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