libsyn.com

Checked 22 October 2026, 09:35 UTC · via 8.8.8.8
!Passed with warnings
25 passed 1 warning 0 failed 5 info

Registration

info

.com generic · Tucows Domains Inc. · expires 2027-10-14

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
Tucows Domains Inc.
Registered
25 October 2004
Last changed
13 October 2026
Expires
14 October 2027
Status
client transfer prohibited, client update prohibited
Registry nameservers
ns1.libsyn.com, ns2.libsyn.com, ns3.libsyn.com, ns4.libsyn.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 2027-10-14 #3
    The registration is valid until 2027-10-14 (357 days).
  • ✓ Transfer locked #4
    Registry status: client transfer prohibited, client update prohibited.
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

info

ns1.libsyn.com, ns2.libsyn.com, ns3.libsyn.com, ns4.libsyn.com

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
ns1.libsyn.com, ns2.libsyn.com, ns3.libsyn.com, ns4.libsyn.com
NS in the zone
ns1.libsyn.com, ns2.libsyn.com, ns3.libsyn.com, ns4.libsyn.com
NameserverAddressesNetwork (AS)Glue
ns1.libsyn.com199.247.152.53 2620:111:8004::53AS32771 DNSIMPLE - DNSimple Corporation, US AS32771 DNSIMPLE - DNSimple Corporation, US199.247.152.53 2620:111:8004::53
ns2.libsyn.com199.247.153.53 2620:111:8005::53AS32771 DNSIMPLE - DNSimple Corporation, US AS32771 DNSIMPLE - DNSimple Corporation, US199.247.153.53 2620:111:8005::53
ns3.libsyn.com199.247.154.53 2620:111:8006::53AS32771 DNSIMPLE - DNSimple Corporation, US AS32771 DNSIMPLE - DNSimple Corporation, US199.247.154.53 2620:111:8006::53
ns4.libsyn.com199.247.155.53 2620:111:8007::53AS32771 DNSIMPLE - DNSimple Corporation, US AS32771 DNSIMPLE - DNSimple Corporation, US199.247.155.53 2620:111:8007::53

Checks

  • ✓ 4 nameservers #6
    Delegated to ns1.libsyn.com, ns2.libsyn.com, ns3.libsyn.com, ns4.libsyn.com.
  • ✓ 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.libsyn.com, ns2.libsyn.com, ns3.libsyn.com, ns4.libsyn.com.
  • ✓ 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 4 IPv6 /48s.
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS32771 (DNSIMPLE - DNSimple Corporation, US): 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 .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

pass

8 of 8 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
ns1.libsyn.com 199.247.152.53NOERROR, 13 ms, authoritativenoyes / yesrefused-
ns1.libsyn.com 2620:111:8004::53NOERROR, 13 ms, authoritativenoyes / yesrefused-
ns2.libsyn.com 199.247.153.53NOERROR, 13 ms, authoritativenoyes / yesrefused-
ns2.libsyn.com 2620:111:8005::53NOERROR, 13 ms, authoritativenoyes / yesrefused-
ns3.libsyn.com 199.247.154.53NOERROR, 14 ms, authoritativenoyes / yesrefused-
ns3.libsyn.com 2620:111:8006::53NOERROR, 14 ms, authoritativenoyes / yesrefused-
ns4.libsyn.com 199.247.155.53NOERROR, 13 ms, authoritativenoyes / yesrefused-
ns4.libsyn.com 2620:111:8007::53NOERROR, 13 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

pass

serial 1582124726 · primary ns1.libsyn.com

Found

Primary (MNAME)
ns1.libsyn.com
Contact (RNAME)
admin.dnsimple.com
Serial
1582124726
Refresh / retry
86400 s / 7200 s
Expire
604800 s
Negative TTL
300 s

Serial per nameserver

NameserverSerial
ns1.libsyn.com (199.247.152.53)1582124726
ns1.libsyn.com (2620:111:8004::53)1582124726
ns2.libsyn.com (199.247.153.53)1582124726
ns2.libsyn.com (2620:111:8005::53)1582124726
ns3.libsyn.com (199.247.154.53)1582124726
ns3.libsyn.com (2620:111:8006::53)1582124726
ns4.libsyn.com (199.247.155.53)1582124726
ns4.libsyn.com (2620:111:8007::53)1582124726

Checks

  • ✓ Serial 1582124726 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 1d, retry 2h, expire 7d, negative TTL 5m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver ns1.libsyn.com is one of the listed nameservers.
  • ✓ Contact admin@dnsimple.com #25
    The SOA RNAME admin.dnsimple.com means admin@dnsimple.com.
  • ✓ Timestamp serial #26
    The serial 1582124726 is a Unix timestamp (2020-02-19 15:05 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

26 records at the apex

Found

Read from
199.247.152.53:53
TypeValueTTL
SOAns1.libsyn.com. admin.dnsimple.com. 1582124726 86400 7200 604800 3003600
NSns1.libsyn.com.3600
NSns2.libsyn.com.3600
NSns3.libsyn.com.3600
NSns4.libsyn.com.3600
A104.19.154.9243200
MX1 aspmx.l.google.com.3600
MX5 alt1.aspmx.l.google.com.3600
MX5 alt2.aspmx.l.google.com.3600
MX10 alt3.aspmx.l.google.com.3600
MX10 alt4.aspmx.l.google.com.3600
TXT"TAILSCALE-T1qOZSt1gTBJmU49DTM1"3600
TXT"anthropic-domain-verification-h5vrbx=668acSu3U1FFzCBrfna2xFLDx"3600
TXT"asv=7769fd0acdd041118a01143aa0234055"3600
TXT"atlassian-domain-verification=qBztE2uTjqxMF2qAF1B9l8GOeAWTU7XZiafuTT7waOIIk8ZrKes1VeSONYH3zNob"3600
TXT"box-domain-verification=1fcff89166854b0fd5c01188d389d04d8ca57fe1af988dec765286367a1e6836"3600
TXT"facebook-domain-verification=dm6rkx5emuyrvngpg41ahpzogw60qh"3600
TXT"google-site-verification=Imh_E3gAalHawooGWucISsw9wfGe2dds1aWOzr3tlXA"3600
TXT"google-site-verification=R4h1bR-p5OEN7LG-zs5R3ep67j8MLDyZYG9kJK3y5Po"3600
TXT"google-site-verification=UAz7lsiSQcgock9lGoa3JVOd-6khpiAZKQNnKy5_HBE"3600
TXT"miro-verification=600fb4225f2708c723b9f819f5e18289ef408fa9"3600
TXT"openai-domain-verification=dv-HRkcoWDY1JaIvtOoWVCRJESu"3600
TXT"pendo-domain-verification=K8UCI-pV4HG1ZZpSBurzy2U6vXU"3600
TXT"s38ll2viooat9frluk366iqmmb"3600
TXT"stripe-verification=4FF48CA0754835CF9AD2E404DCCC31391535BE44972F9F3B1DC631C25B74BFEC"3600
TXT"v=spf1 a mx include:spf.mtasv.net include:spf.braintreegateway.com include:mail.zendesk.com ip4:207.126.144.0/20 ip4:64.18.0.0/20 ip4:74.125.148.0/22 include:_spf.google.com include:3391700.spf04.hubspotemail.net -all"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 12h, MX 1h, NS 1h. The NS TTL at the parent is 2d and in the zone 1h; 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