labcorp.com

Checked 22 October 2026, 09:33 UTC · via 8.8.8.8
✗Problems found
24 passed 2 warnings 1 failed 4 info

Registration

info

.com generic · CSC Corporate Domains, Inc. · expires 2027-07-10

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
CSC Corporate Domains, Inc.
Registered
11 July 1995
Last changed
6 July 2026
Expires
10 July 2027
Status
client transfer prohibited, server delete prohibited, server transfer prohibited, server update prohibited
Registry nameservers
dns3.labcorp.com, dns4.labcorp.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 2027-07-10 #3
    The registration is valid until 2027-07-10 (260 days).
  • ✓ Transfer locked #4
    Registry status: client transfer prohibited, server delete prohibited, server transfer prohibited, server update prohibited.
  • ✓ Registry and delegation match #5
    The nameservers registered at the registry are the ones published in DNS.

Delegation

warn

dns3.labcorp.com, dns4.labcorp.com

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
dns3.labcorp.com, dns4.labcorp.com
NS in the zone
dns3.labcorp.com, dns4.labcorp.com
NameserverAddressesNetwork (AS)Glue
dns3.labcorp.com162.134.164.164AS53768 LABCORP - Laboratory Corporation of America, US162.134.164.164
dns4.labcorp.com162.134.132.77AS18994 LABCORP-BLS - Laboratory Corporation of America, US162.134.132.77

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: dns3.labcorp.com, dns4.labcorp.com.
    #6
  • ✓ 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: dns3.labcorp.com, dns4.labcorp.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 2 IPv4 /24s and 0 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS18994 (LABCORP-BLS - Laboratory Corporation of America, US): 1 address; AS53768 (LABCORP - Laboratory Corporation of America, US): 1 address.
  • 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
  • !
    No IPv6
    None of the nameservers has an IPv6 address, so IPv6-only resolvers can't reach them.
    #13

Nameservers

fail

1 of 2 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns3.labcorp.com 162.134.164.164NOERROR, 108 ms, authoritativenoyes / yesrefused-
dns4.labcorp.com 162.134.132.77no responsenono / no--

Checks

  • ✗
    Nameservers not responding
    These addresses did not answer, so resolvers waste time on timeouts: dns4.labcorp.com (162.134.132.77): read udp 46.225.38.91:33803->162.134.132.77:53: i/o timeout.
    #14
  • ✓ 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 2014094077 · primary dns3.labcorp.com

Found

Primary (MNAME)
dns3.labcorp.com
Contact (RNAME)
internetdomainadmin.labcorp.com
Serial
2014094077
Refresh / retry
10800 s / 3600 s
Expire
2419200 s
Negative TTL
900 s

Checks

  • ✓ Serial 2014094077 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 3h, retry 1h, expire 28d, negative TTL 15m.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns3.labcorp.com is one of the listed nameservers.
  • ✓ Contact internetdomainadmin@labcorp.com #25
    The SOA RNAME internetdomainadmin.labcorp.com means internetdomainadmin@labcorp.com.
  • ✓ Timestamp serial #26
    The serial 2014094077 is a Unix timestamp (2033-10-28 06:34 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

40 records at the apex

Found

Read from
162.134.164.164:53
TypeValueTTL
SOAdns3.labcorp.com. internetdomainadmin.labcorp.com. 2014094077 10800 3600 2419200 90028800
NSdns4.labcorp.com.28800
NSdns3.labcorp.com.28800
A104.18.31.6028800
A104.18.30.6028800
MX10 mx0a-00266502.pphosted.com.3600
MX10 mx0b-00266502.pphosted.com.3600
TXT"MS=ms55992890"300
TXT"cisco-ci-domain-verification=373ac705c3db07bc63e48289bc0759d862eba2cbfdd5c53be42b23e86b3cdc07"300
TXT"amazonses:C7qgWYqHUrDBdd2SKS9hGrWoVZ0gUMB463agQijRqtI="300
TXT"amazonses:CvC5HNT8sR/fVcBjZSuzPGFc56HtC2g60duA+HrWWcw="300
TXT"onetrust-domain-verification=50e215ef57e04636ba0fb405b169caee"300
TXT"amazonses:ftIJEBfa23pDi1VQHWTHPeLh/e6h8ibzed5JmllFaZU="300
TXT"amazonses:GaysHhsPuerYh62udkdu/JJO/T51m1xh/LS/3QxzMvA="300
TXT"google-site-verification=nS29-b3aiPzYlTcvVsbmBNO9pIPQ3K-w9W76716EvpE"300
TXT"Dynatrace-site-verification=f19de573-c4c1-4e8f-8677-1e4714c46517__mm12fi6eckfua6g7il8k9vopqd"300
TXT"docusign=40b7a632-6852-4145-ac76-1cf19ae47b29"300
TXT"docusign=af61972d-5648-4437-970a-98b9472f472d"300
TXT"xz3yz7kxt5gz8h44pw43ntgmgp638ldv"300
TXT"google-site-verification=K8J62PNnBJDUegN9vyRiOxaK722gvJQ0RyE_4up-B34"300
TXT"smartsheet-site-validation=8ivDZqSPWhpNIpG7jEhrZ1B7I8T1pH2b"300
TXT"flexera-domain-verification-eqiljatgjfitjxei"300
TXT"adobe-idp-site-verification=fa373cc635a85d4230f783cb97266eefb65c34e4ed1574253364969e82f96e52"300
TXT"ecostruxure-it-verification=088dcb9c-9cf4-4060-899a-f54149baa95a"300
TXT"facebook-domain-verification=wab7s18vblggua9dpr6uatd46s6dar"300
TXT"atlassian-domain-verification=gXRqVpj7GqfeuuHa730E8kXVvPSlG8dUuCpJ7uYVsshV61ErxAXzIKCS2AvmogSK"300
TXT"miro-verification=be22b8192b1095104f7a62c95a71a9a5af034195"300
TXT"QlQ6Qcyt-F-y383IsONjVDOrYQ"300
TXT"lucid-validate-BwAA5kDhIhAnhwDf0kPq"300
TXT"atlassian-domain-verification=qxlPoHuIMpPekKAhAw3eIBw5lnDwSDn5SbbZCFsStOEi6RTpeFgzyiu1D+1dNhrV"300
TXT"_1mxkql0c4w95pydum27g0rbg8f3g5w7"300
TXT"arcules-domain-verification=9Cc1CIbiCpn1PTKEMdrDgwE5OnJvpMb2nqKlbUBx9hp"300
TXT"cursor-domain-verification-7wpd5n=KBX70uv7vxiR7zuBnNbDDLfJX"300
TXT"_fiyd58xt3qrka6vvxt3eebbz5b65zmb"300
TXT"atlassian-domain-verification=b2VZbQ3BAZssE8wUiX4v07p1JOcBkmo3mGahk1Gmd9BqiOb2WjLBzAQu3Snfp0/f"300
TXT"anthropic-domain-verification-p1pe1r=IUTBYMeq9hyxH16WNdf8rEnQk"300
TXT"jamf-site-verification=eP2zFKa-azUJZuYOrvXXWA"300
TXT"_9iwk12gzk05qu0lauaaudbclegmv6fw"300
TXT"v=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com ~all"300
TXT"IW6CrL7/xzLIHQ/Na42eD4o1eqT2BJHASysrki0JErh/0RogVDiXePEjzwX7AUUzUmnJDV2IN74op2zI8TkJXA=="300

Checks

  • ✓ TTLs within range #32
    TTLs: A 8h, MX 1h, NS 8h. The NS TTL at the parent is 2d and in the zone 8h; 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