uk.linkedin.com

Zone linkedin.com · Checked 22 October 2026, 11:15 UTC · via 8.8.8.8
!Passed with warnings
25 passed 4 warnings 0 failed 2 info

Registration

info

.com generic · MarkMonitor Inc. · expires 2027-11-02

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
MarkMonitor Inc.
Registered
2 November 2002
Last changed
1 October 2026
Expires
2 November 2027
Status
client delete prohibited, client transfer prohibited, client update prohibited, server delete prohibited, server transfer prohibited, server update prohibited
Registry nameservers
dns1.p09.nsone.net, dns2.p09.nsone.net, dns3.p09.nsone.net, dns4.p09.nsone.net, ns1-42.azure-dns.com, ns2-42.azure-dns.net, ns3-42.azure-dns.org, ns4-42.azure-dns.info
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 2027-11-02 #3
    The registration is valid until 2027-11-02 (376 days).
  • ✓ Transfer locked #4
    Registry status: client delete prohibited, client transfer prohibited, client update 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

info

dns1.p09.nsone.net, dns2.p09.nsone.net, dns3.p09.nsone.net, dns4.p09.nsone.net, ns1-42.azure-dns.com, ns2-42.azure-dns.net, ns3-42.azure-dns.org, ns4-42.azure-dns.info

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
dns1.p09.nsone.net, dns2.p09.nsone.net, dns3.p09.nsone.net, dns4.p09.nsone.net, ns1-42.azure-dns.com, ns2-42.azure-dns.net, ns3-42.azure-dns.org, ns4-42.azure-dns.info
NS in the zone
dns1.p09.nsone.net, dns2.p09.nsone.net, dns3.p09.nsone.net, dns4.p09.nsone.net, ns1-42.azure-dns.com, ns2-42.azure-dns.net, ns3-42.azure-dns.org, ns4-42.azure-dns.info
NameserverAddressesNetwork (AS)Glue
dns1.p09.nsone.net198.51.44.9 2620:4d:4000:6259:7:9:0:1AS62597 NSONE - NSONE Inc, US AS62597 NSONE - NSONE Inc, US-
dns2.p09.nsone.net198.51.45.9 2a00:edc0:6259:7:9::2AS62597 NSONE - NSONE Inc, US AS62597 NSONE - NSONE Inc, US-
dns3.p09.nsone.net198.51.44.73 2620:4d:4000:6259:7:9:0:3AS62597 NSONE - NSONE Inc, US AS62597 NSONE - NSONE Inc, US-
dns4.p09.nsone.net198.51.45.73 2a00:edc0:6259:7:9::4AS62597 NSONE - NSONE Inc, US AS62597 NSONE - NSONE Inc, US-
ns1-42.azure-dns.com150.171.10.42AS8075 MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US150.171.10.42
ns2-42.azure-dns.net150.171.16.42AS8075 MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US-
ns3-42.azure-dns.org13.107.222.42AS8075 MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US-
ns4-42.azure-dns.info13.107.206.42AS8075 MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US-

Checks

  • ✓ 8 nameservers #6
    Delegated to dns1.p09.nsone.net, dns2.p09.nsone.net, dns3.p09.nsone.net, dns4.p09.nsone.net, ns1-42.azure-dns.com, ns2-42.azure-dns.net, ns3-42.azure-dns.org, ns4-42.azure-dns.info.
  • ✓ 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 6 IPv4 /24s and 2 IPv6 /48s.
  • ✓ 2 autonomous systems #11
    The nameservers are spread over: AS62597 (NSONE - NSONE Inc, US): 8 addresses; AS8075 (MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US): 4 addresses.
  • ✓ Nameserver names under 4 TLDs #12
    Nameserver names use the TLDs .com, .info, .net, .org.
  • i
    Partly IPv6
    These nameservers have no IPv6 address: ns1-42.azure-dns.com, ns2-42.azure-dns.net, ns3-42.azure-dns.org, ns4-42.azure-dns.info.
    #13

Nameservers

warn

12 of 12 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns1.p09.nsone.net 198.51.44.9NOERROR, 5 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
dns1.p09.nsone.net 2620:4d:4000:6259:7:9:0:1NOERROR, 4 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
dns2.p09.nsone.net 198.51.45.9NOERROR, 4 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
dns2.p09.nsone.net 2a00:edc0:6259:7:9::2NOERROR, 4 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
dns3.p09.nsone.net 198.51.44.73NOERROR, 6 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
dns3.p09.nsone.net 2620:4d:4000:6259:7:9:0:3NOERROR, 4 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
dns4.p09.nsone.net 198.51.45.73NOERROR, 4 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
dns4.p09.nsone.net 2a00:edc0:6259:7:9::4NOERROR, 4 ms, authoritativenoyes / yesrefused19dd46e347df36b70933bf2be8023258586586a9
ns1-42.azure-dns.com 150.171.10.42NOERROR, 4 ms, authoritativenoyes / yesrefused-
ns2-42.azure-dns.net 150.171.16.42NOERROR, 4 ms, authoritativenoyes / yesrefusedKnot DNS 3.1.2.1770717641.d6b376aff
ns3-42.azure-dns.org 13.107.222.42NOERROR, 4 ms, authoritativenoyes / yesrefused-
ns4-42.azure-dns.info 13.107.206.42NOERROR, 4 ms, authoritativenoyes / yesrefusedKnot DNS 3.1.2.1770717641.d6b376aff

Checks

  • ✓ All respond #14
    All 12 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: ns2-42.azure-dns.net: "Knot DNS 3.1.2.1770717641.d6b376aff"; ns4-42.azure-dns.info: "Knot DNS 3.1.2.1770717641.d6b376aff". 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

warn

serial 1789612855 · primary dns1.p09.nsone.net

Found

Primary (MNAME)
dns1.p09.nsone.net
Contact (RNAME)
hostmaster.linkedin.com
Serial
1789612855
Refresh / retry
3600 s / 600 s
Expire
604800 s
Negative TTL
60 s

Serial per nameserver

NameserverSerial
dns1.p09.nsone.net (198.51.44.9)1789612855
dns1.p09.nsone.net (2620:4d:4000:6259:7:9:0:1)1789612855
dns2.p09.nsone.net (198.51.45.9)1789612855
dns2.p09.nsone.net (2a00:edc0:6259:7:9::2)1789612855
dns3.p09.nsone.net (198.51.44.73)1789612855
dns3.p09.nsone.net (2620:4d:4000:6259:7:9:0:3)1789612855
dns4.p09.nsone.net (198.51.45.73)1789612855
dns4.p09.nsone.net (2a00:edc0:6259:7:9::4)1789612855
ns1-42.azure-dns.com (150.171.10.42)1
ns2-42.azure-dns.net (150.171.16.42)1
ns3-42.azure-dns.org (13.107.222.42)1
ns4-42.azure-dns.info (13.107.206.42)1

Checks

  • !
    Serials differ
    The nameservers serve different versions of the zone: 1 on ns1-42.azure-dns.com (150.171.10.42), ns2-42.azure-dns.net (150.171.16.42), ns3-42.azure-dns.org (13.107.222.42), ns4-42.azure-dns.info (13.107.206.42); 1789612855 on dns1.p09.nsone.net (198.51.44.9), dns1.p09.nsone.net (2620:4d:4000:6259:7:9:0:1), dns2.p09.nsone.net (198.51.45.9), dns2.p09.nsone.net (2a00:edc0:6259:7:9::2), dns3.p09.nsone.net (198.51.44.73), dns3.p09.nsone.net (2620:4d:4000:6259:7:9:0:3), dns4.p09.nsone.net (198.51.45.73), dns4.p09.nsone.net (2a00:edc0:6259:7:9::4). This is normal for a few minutes after a change; if it lasts, zone transfers to the secondaries are failing.
    #22
  • !
    Unusual SOA timers
    negative caching TTL (minimum) 1m is outside 5m–1d (RFC 2308 recommends 1–3 hours). Current values: refresh 1h, retry 10m, expire 7d, negative TTL 1m.
    #23
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns1.p09.nsone.net is one of the listed nameservers.
  • ✓ Contact hostmaster@linkedin.com #25
    The SOA RNAME hostmaster.linkedin.com means hostmaster@linkedin.com.
  • ✓ Timestamp serial #26
    The serial 1789612855 is a Unix timestamp (2026-09-17 02:40 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

pass

43 records at the apex

Found

Read from
198.51.44.9:53
TypeValueTTL
SOAdns1.p09.nsone.net. hostmaster.linkedin.com. 1789612855 3600 600 604800 603600
NSdns1.p09.nsone.net.86400
NSdns2.p09.nsone.net.86400
NSdns3.p09.nsone.net.86400
NSdns4.p09.nsone.net.86400
NSns1-42.azure-dns.com.86400
NSns2-42.azure-dns.net.86400
NSns3-42.azure-dns.org.86400
NSns4-42.azure-dns.info.86400
A130.211.32.14300
AAAA2600:1901:0:d5ad::300
MX10 mail-1.linkedin.com.300
MX10 mail-2.linkedin.com.300
MX10 mail-d.linkedin.com.300
MX20 mail-a.linkedin.com.300
MX20 mail-c.linkedin.com.300
MX20 mail.linkedin.com.300
TXT"448e0dc03e935ecf66d81f1ce3c26b2f2fea13756c031ffc4be91749107f3a79"86400
TXT"AFDVALIDATION=LinkedIn"86400
TXT"_cthqqp5zj8g86qf3h97heqitg2zc32b"86400
TXT"apple-domain-verification=Hp7LihDNsREwfHX9"86400
TXT"atlassian-domain-verification=dDed2VFvlDajBX8X22w52Jx/W/YLHR81SxUuraa9zNdz4aLjDS/RpfN11w2bxpRc"86400
TXT"atlassian-domain-verification=juKdSE4GGphSmzPkhmnRJUNIn0ALdb0vsP7VSPM8TmTP7WgbgUQPLFdNicP7bF58"86400
TXT"atlassian-sending-domain-verification=3bdb0597-814d-4e10-a552-5cf78f92ab3c"86400
TXT"bf5fl8sny79w4c70jxp6cp3crkqtr7qk"86400
TXT"bluebeam-verification=02px6k8snlrzd6gx3b3oqkeatbzawd"86400
TXT"docusign=11f01284-dffc-40f9-8d56-57e5261ede3f"86400
TXT"elevenlabs=hRLt8nemUjAWJSL_xhBIsKFyK4yYV089AvwkOB0cxYY"86400
TXT"google-site-verification=0Vs9yf1V6RGkuzow85OzIXKEnjpRswpDkI6RgDVspMg"86400
TXT"google-site-verification=8LaIeBMwr6K8qWeaGa4CEmfPKiZDwaT38t5mIrtaroI"86400
TXT"google-site-verification=VE9BWhjbPPNmbr3ZJcwn5hLTsz7c5KPt3zXdYyaSnSQ"86400
TXT"google-site-verification=X0LoSQsAMzR-TK4o-ULrYAwLi_fyopfRLkm_C-4N4Ts"86400
TXT"google-site-verification=anx3jpa6VKkTWRJKnglUIzm7UEn-ZCT2WqAfG7h-xOg"86400
TXT"google-site-verification=mMV_EnYaB52OhMo-jbNowf8QVIKcXV3WpXreynLFFEo"86400
TXT"google-site-verification=oJFWbtlKRblXs4smNibcoJkTJqwT6gd3XMI80VjBihE"86400
TXT"google-site-verification=vfmYHwjzUIFPzxFcyuwEToh_1kG9wvcpGgJnB-MhQn8"86400
TXT"google-site-verification=xAGz495k8RbGclhamQx1TkZSHDxOaEd95fOjc8xpbTA"86400
TXT"liveramp-site-verification=yQ2nkwhqszpGRQg_J38S60KHInPVs-dclgyNRtRrlBA"86400
TXT"miro-verification=260f00146b6d2ad1bb70d6dc07a077b672badd28"86400
TXT"v=spf1 ip4:199.101.162.0/25 ip4:108.174.3.0/24 ip4:108.174.6.0/24 ip4:108.174.0.0/24 ip6:2620:109:c00d:104::/64 ip6:2620:109:c006:104::/64 ip6:2620:109:c003:104::/64 ip6:2620:119:50c0:207::/64 ip4:199.101.161.130 mx mx:docusign.net ~all"86400
TXT"vmware-cloud-verification-f4d7c1c7-ad66-450f-82fa-c17b9ee79459"86400
CAA0 contactemail "caarecordaware@microsoft.com"3600
CAA0 contactemail "tls-alerts@linkedin.com"3600

Checks

  • ✓ TTLs within range #32
    TTLs: A 5m, AAAA 5m, MX 5m, NS 1d. The NS TTL at the parent is 2d and in the zone 1d; 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.
  • ✓ CAA restricts issuance #35
    Certificates may be issued by: .