seobook.com

Checked 22 October 2026, 10:40 UTC · via 8.8.8.8
!Passed with warnings
24 passed 2 warnings 0 failed 5 info

Registration

info

.com generic · NameCheap, Inc. · expires 2027-07-04

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
NameCheap, Inc.
Registered
24 July 2003
Last changed
4 June 2026
Expires
4 July 2027
Status
client transfer prohibited
Registry nameservers
ns1.linode.com, ns2.linode.com, ns3.linode.com, ns4.linode.com, ns5.linode.com
RDAP server
https://rdap.verisign.com/com/v1/

Checks

  • i
    .com is a generic TLD (gTLD)
    Generic TLD under an ICANN registry agreement: ICANN-accredited registrars, UDRP and RDAP apply.
    #1
  • ✓ TLD delegated and signed #2
    .com is delegated in the root zone and DNSSEC-signed.
  • ✓ Expires on 2027-07-04 #3
    The registration is valid until 2027-07-04 (254 days).
  • ✓ Transfer locked #4
    Registry status: client transfer prohibited.
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

info

ns1.linode.com, ns2.linode.com, ns3.linode.com, ns4.linode.com, ns5.linode.com

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
ns1.linode.com, ns2.linode.com, ns3.linode.com, ns4.linode.com, ns5.linode.com
NS in the zone
ns1.linode.com, ns2.linode.com, ns3.linode.com, ns4.linode.com, ns5.linode.com
NameserverAddressesNetwork (AS)Glue
ns1.linode.com92.123.94.2 2600:14c0:6::2AS21342 AKAMAI-ASN2 - Akamai International B.V., NL AS21342 AKAMAI-ASN2 - Akamai International B.V., NL2600:14c0:6::2 92.123.94.2
ns2.linode.com92.123.94.3 2600:14c0:6::3AS21342 AKAMAI-ASN2 - Akamai International B.V., NL AS21342 AKAMAI-ASN2 - Akamai International B.V., NL2600:14c0:6::3 92.123.94.3
ns3.linode.com92.123.95.3 2600:14c0:7::3AS21342 AKAMAI-ASN2 - Akamai International B.V., NL AS21342 AKAMAI-ASN2 - Akamai International B.V., NL2600:14c0:7::3 92.123.95.3
ns4.linode.com92.123.95.4 2600:14c0:7::4AS21342 AKAMAI-ASN2 - Akamai International B.V., NL AS21342 AKAMAI-ASN2 - Akamai International B.V., NL2600:14c0:7::4 92.123.95.4
ns5.linode.com92.123.95.2 2600:14c0:7::2AS21342 AKAMAI-ASN2 - Akamai International B.V., NL AS21342 AKAMAI-ASN2 - Akamai International B.V., NL2600:14c0:7::2 92.123.95.2

Checks

  • ✓ 5 nameservers #6
    Delegated to ns1.linode.com, ns2.linode.com, ns3.linode.com, ns4.linode.com, ns5.linode.com.
  • ✓ 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 2 IPv4 /24s and 2 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS21342 (AKAMAI-ASN2 - Akamai International B.V., NL): 10 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 .com
    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

10 of 10 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns1.linode.com 92.123.94.2NOERROR, 15 ms, authoritativenoyes / yesrefused-
ns1.linode.com 2600:14c0:6::2NOERROR, 16 ms, authoritativenoyes / yesrefusedLinode.com DNS
ns2.linode.com 92.123.94.3NOERROR, 149 ms, authoritativenoyes / yesrefused-
ns2.linode.com 2600:14c0:6::3NOERROR, 16 ms, authoritativenoyes / yesrefusedLinode.com DNS
ns3.linode.com 92.123.95.3NOERROR, 84 ms, authoritativenoyes / yesrefusedLinode.com DNS
ns3.linode.com 2600:14c0:7::3NOERROR, 16 ms, authoritativenoyes / yesrefusedLinode.com DNS
ns4.linode.com 92.123.95.4NOERROR, 16 ms, authoritativenoyes / yesrefusedLinode.com DNS
ns4.linode.com 2600:14c0:7::4NOERROR, 15 ms, authoritativenoyes / yesrefusedLinode.com DNS
ns5.linode.com 92.123.95.2NOERROR, 15 ms, authoritativenoyes / yesrefusedLinode.com DNS
ns5.linode.com 2600:14c0:7::2NOERROR, 16 ms, authoritativenoyes / yesrefusedLinode.com DNS

Checks

  • ✓ All respond #14
    All 10 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.linode.com: "Linode.com DNS"; ns2.linode.com: "Linode.com DNS"; ns3.linode.com: "Linode.com DNS"; ns4.linode.com: "Linode.com DNS"; ns5.linode.com: "Linode.com DNS".
    #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 2021000005 · primary ns1.linode.com

Found

Primary (MNAME)
ns1.linode.com
Contact (RNAME)
seobook\.com.domainsbyproxy.com
Serial
2021000005
Refresh / retry
14400 s / 14400 s
Expire
1209600 s
Negative TTL
86400 s

Serial per nameserver

NameserverSerial
ns1.linode.com (92.123.94.2)2021000005
ns1.linode.com (2600:14c0:6::2)2021000005
ns2.linode.com (92.123.94.3)2021000005
ns2.linode.com (2600:14c0:6::3)2021000005
ns3.linode.com (92.123.95.3)2021000005
ns3.linode.com (2600:14c0:7::3)2021000005
ns4.linode.com (92.123.95.4)2021000005
ns4.linode.com (2600:14c0:7::4)2021000005
ns5.linode.com (92.123.95.2)2021000005
ns5.linode.com (2600:14c0:7::2)2021000005

Checks

  • ✓ Serial 2021000005 everywhere #22
    All nameservers serve the same version of the zone.
  • !
    Unusual SOA timers
    retry 4h should be shorter than refresh 4h. Current values: refresh 4h, retry 4h, expire 14d, negative TTL 1d.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.linode.com is one of the listed nameservers.
  • ✓ Contact seobook.com@domainsbyproxy.com #25
    The SOA RNAME seobook\.com.domainsbyproxy.com means seobook.com@domainsbyproxy.com.
  • ✓ Timestamp serial #26
    The serial 2021000005 is a Unix timestamp (2034-01-16 04:53 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

11 records at the apex

Found

Read from
92.123.94.2:53
TypeValueTTL
SOAns1.linode.com. SEOBOOK\.COM.domainsbyproxy.com. 2021000005 14400 14400 1209600 8640086397
NSns2.linode.com.86397
NSns3.linode.com.86397
NSns4.linode.com.86397
NSns5.linode.com.86397
NSns1.linode.com.86397
A45.79.65.12086400
AAAA2600:3c01::f03c:91ff:fe3b:f4ff86400
MX10 seobook.com.86400
TXT"v=spf1 a mx ip4:45.79.65.120 -all"86400
TXT"google-site-verification=hN-ngnOLbM7FOlOTNyA8-gobdTwmv9LsBXbK6ZmKY5g"86400

Checks

  • ✓ TTLs within range #32
    TTLs: A 1d, AAAA 1d, MX 1d, NS 23h59m57s. The NS TTL at the parent is 2d and in the zone 23h59m57s; 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