zhongguowangshi.com

ns1.dnsv4.com, ns2.dnsv4.com

Found

Parent zone

com

Delegation from

a.gtld-servers.net (192.5.6.30)

NS at the parent

ns1.dnsv4.com, ns2.dnsv4.com

NS in the zone

ns1.dnsv4.com, ns2.dnsv4.com

Checks

• i

  2 nameservers

  Two nameservers meet the minimum; RFC 2182 recommends three or more for important zones: ns1.dnsv4.com, ns2.dnsv4.com.

  #6
• ✓ 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 12 IPv4 /24s and 0 IPv6 /48s.
• ✓ 9 autonomous systems #11

  The nameservers are spread over: AS132203 (TENCENT-NET-AP-CN - Tencent Building, Kejizhongyi Avenue, CN): 3 addresses; AS134756 (ChinaNet-NANJING-JISHAN-IDC - CHINANET Nanjing Jishan IDC network, CN): 1 address; AS136958 (UNICOM-GuangZhou-IDC - China Unicom Guangdong IP network, CN): 1 address; AS17621 (CNCGROUP-SH - China Unicom Shanghai network, CN): 1 address; AS4134 (CHINANET-BACKBONE - No.31,Jin-rong Street, CN): 1 address; AS45090 (TENCENT-NET-AP - Shenzhen Tencent Computer Systems Company Limited, CN): 4 addresses; AS4811 (CHINANET-SHANGHAI-MAN - China Telecom (Group), CN): 1 address; AS56046 (CMNET-Jiangsu-AP - China Mobile communications corporation, CN): 1 address; AS9808 (CHINAMOBILE-CN - China Mobile Communications Group Co., Ltd., CN): 2 addresses.
• 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

15 of 15 addresses answer authoritatively

Found

Checks

• ✓ All respond #14

  All 15 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: ns1.dnsv4.com: "DNSPod AUTHORITY DNS 7.3.2512.01"; ns2.dnsv4.com: "DNSPod AUTHORITY DNS 7.3.2512.01". 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.

serial 1754530786 · primary ns1.dnsv4.com

Found

Primary (MNAME)

ns1.dnsv4.com

Contact (RNAME)

enterprise2dnsadmin.dnspod.com

Serial

1754530786

Refresh / retry

3600 s / 180 s

Expire

1209600 s

Negative TTL

180 s

Serial per nameserver

Checks

• ✓ Serial 1754530786 everywhere #22

  All nameservers serve the same version of the zone.
• !

  Unusual SOA timers

  negative caching TTL (minimum) 3m is outside 5m–1d (RFC 2308 recommends 1–3 hours). Current values: refresh 1h, retry 3m, expire 14d, negative TTL 3m.

  #23
• ✓ Primary is a public nameserver #24

  The primary nameserver ns1.dnsv4.com is one of the listed nameservers.
• ✓ Contact enterprise2dnsadmin@dnspod.com #25

  The SOA RNAME enterprise2dnsadmin.dnspod.com means enterprise2dnsadmin@dnspod.com.
• ✓ Timestamp serial #26

  The serial 1754530786 is a Unix timestamp (2025-08-07 01:39 UTC).

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