memtest86.com

Checked 22 October 2026, 09:44 UTC · via 8.8.8.8
!Passed with warnings
21 passed 3 warnings 0 failed 7 info

Registration

info

.com generic · pair Networks, Inc. d/b/a pair Domains · expires 2031-06-12

Found

TLD
.com (generic)
ICANN policies apply
yes
Registrar
pair Networks, Inc. d/b/a pair Domains
Registered
12 June 2001
Last changed
25 June 2026
Expires
12 June 2031
Status
client transfer prohibited
Registry nameservers
ns2.quickserve.com, ns7.ns0.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 2031-06-12 #3
    The registration is valid until 2031-06-12 (1694 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

warn

ns2.quickserve.com, ns7.ns0.com

Found

Parent zone
com
Delegation from
a.gtld-servers.net (192.5.6.30)
NS at the parent
ns2.quickserve.com, ns7.ns0.com
NS in the zone
dns4.pair.com, ns7.ns0.com
NameserverAddressesNetwork (AS)Glue
dns4.pair.com (zone only)216.92.252.10 2607:f440::d85c:fc0aAS7859 PAIR-NETWORKS - pair Networks, US AS7859 PAIR-NETWORKS - pair Networks, US-
ns2.quickserve.com (parent only)66.39.65.254AS7859 PAIR-NETWORKS - pair Networks, US66.39.65.254
ns7.ns0.com216.92.151.254 2607:f440::d85c:97feAS7859 PAIR-NETWORKS - pair Networks, US AS7859 PAIR-NETWORKS - pair Networks, US216.92.151.254 2607:f440::d85c:97fe

Checks

  • i
    2 nameservers
    Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns2.quickserve.com, ns7.ns0.com.
    #6
  • !
    NS sets differ
    The nameservers at the parent and in the zone should be the same. Only at the parent: ns2.quickserve.com; only in the zone: dns4.pair.com. dns4.pair.com, ns2.quickserve.com, ns7.ns0.com report NS dns4.pair.com ns7.ns0.com.
    #7
  • ✓ 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.
  • i
    One address family in one network
    all IPv6 addresses are in 2607:f440::/48, while the other address family is spread over several networks.
    #10
  • i
    All nameservers in one AS
    All nameserver addresses are announced by one network operator (AS7859 (PAIR-NETWORKS - pair Networks, US): 5 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
  • i
    Partly IPv6
    These nameservers have no IPv6 address: ns2.quickserve.com.
    #13

Nameservers

warn

5 of 5 addresses answer authoritatively

Found

NameserverAnswerRecursionTCP / EDNSAXFRVersion
dns4.pair.com 216.92.252.10NOERROR, 93 ms, authoritativenoyes / yesrefused9.20.29
dns4.pair.com 2607:f440::d85c:fc0aNOERROR, 93 ms, authoritativenoyes / yesrefused9.20.29
ns2.quickserve.com 66.39.65.254NOERROR, 90 ms, authoritativenoyes / yesrefused9.20.29
ns7.ns0.com 216.92.151.254NOERROR, 93 ms, authoritativenoyes / yesrefused9.20.29
ns7.ns0.com 2607:f440::d85c:97feNOERROR, 93 ms, authoritativenoyes / yesrefused9.20.29

Checks

  • ✓ All respond #14
    All 5 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: dns4.pair.com: "9.20.29"; ns2.quickserve.com: "9.20.29"; ns7.ns0.com: "9.20.29". 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

pass

serial 2026091510 · primary dns4.pair.com

Found

Primary (MNAME)
dns4.pair.com
Contact (RNAME)
root.pair.com
Serial
2026091510
Refresh / retry
3600 s / 300 s
Expire
604800 s
Negative TTL
3600 s

Serial per nameserver

NameserverSerial
dns4.pair.com (216.92.252.10)2026091510
dns4.pair.com (2607:f440::d85c:fc0a)2026091510
ns2.quickserve.com (66.39.65.254)2026091510
ns7.ns0.com (216.92.151.254)2026091510
ns7.ns0.com (2607:f440::d85c:97fe)2026091510

Checks

  • ✓ Serial 2026091510 everywhere #22
    All nameservers serve the same version of the zone.
  • ✓ Timers within recommendations #23
    SOA refresh 1h, retry 5m, expire 7d, negative TTL 1h.
  • ✓ Primary is a public nameserver #24
    The primary nameserver dns4.pair.com is one of the listed nameservers.
  • ✓ Contact root@pair.com #25
    The SOA RNAME root.pair.com means root@pair.com.
  • ✓ Date-based serial #26
    The serial 2026091510 follows the YYYYMMDDnn convention (2026-09-15).

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

6 records at the apex

Found

Read from
216.92.252.10:53
TypeValueTTL
SOAdns4.pair.com. root.pair.com. 2026091510 3600 300 604800 3600600
NSns7.ns0.com.600
NSdns4.pair.com.600
A216.146.215.39600
MX50 qs4674.pair.com.600
TXT"v=spf1 mx a -all"600

Checks

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