21cnbook.com - robtex.com

21cnbook.com

DNSSEC⚠️ Not signed
A2606:4700:3032::6815:44e6🇺🇸 Cloudflare2606:4700:3032::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints
A2606:4700:3036::ac43:c782🇺🇸 Cloudflare2606:4700:3036::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints
A104.21.68.230Cloudflare104.21.64.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints
A172.67.199.130🇺🇸 Cloudflare172.67.192.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints
NSjocelyn.ns.cloudflare.com ⭐
A2606:4700:50::adf5:3aae🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjocelyn.ns.cloudflare.com
A2803:f800:50::6ca2:c0ae🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L
PTRjocelyn.ns.cloudflare.com
A2a06:98c1:50::ac40:20ae🇺🇸 Cloudflare2a06:98c1:50::/45
PTRjocelyn.ns.cloudflare.com
A108.162.192.174🇺🇸 Cloudflare108.162.192.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjocelyn.ns.cloudflare.com
A172.64.32.174🇺🇸 Cloudflare172.64.32.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjocelyn.ns.cloudflare.com
A173.245.58.174🇺🇸 Cloudflare173.245.58.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjocelyn.ns.cloudflare.com
NSmarty.ns.cloudflare.com
A2606:4700:58::adf5:3bcc🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRmarty.ns.cloudflare.com
A2803:f800:50::6ca2:c1cc🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L
PTRmarty.ns.cloudflare.com
A2a06:98c1:50::ac40:21cc🇺🇸 Cloudflare2a06:98c1:50::/45
PTRmarty.ns.cloudflare.com
A108.162.193.204🇺🇸 Cloudflare108.162.193.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRmarty.ns.cloudflare.com
A172.64.33.204🇺🇸 Cloudflare172.64.33.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRmarty.ns.cloudflare.com
A173.245.59.204🇺🇸 Cloudflare173.245.59.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRmarty.ns.cloudflare.com
HTTPSHTTP/3, HTTP/2 ✓ hints match
IPv4104.21.68.230, 172.67.199.130
IPv62606:4700:3032::6815:44e6, 2606:4700:3036::ac43:c782
SOAjocelyn.ns.cloudflare.comdns@cloudflare.com serial=2399497689

com

DNSSEC🔒 Signed (DS record present)
NSa.gtld-servers.net ⭐
NSb.gtld-servers.net
NSc.gtld-servers.net
NSd.gtld-servers.net
NSe.gtld-servers.net
NSf.gtld-servers.net
NSg.gtld-servers.net
NSh.gtld-servers.net
NSi.gtld-servers.net
NSj.gtld-servers.net
NSk.gtld-servers.net
NSl.gtld-servers.net
NSm.gtld-servers.net
SOAa.gtld-servers.netnstld@verisign-grs.com serial=1774380302

Same first word

21cnbook.com

DNS History

16 records (6 active, 10 former)

20162017201820192020202120222023202420252026NSjocelyn.ns.cloudflare.commarty.ns.cloudflare.comns.chinaccnet.netns1.51dns.comns1.chinaccnet.netns2.51dns.comns2.chinaccnet.netns3.chinaccnet.netns6.dnsdun.comns6.dnsdun.netA104.21.68.230172.67.199.1302606:4700:3032::6815:44e62606:4700:3036::ac43:c782103.47.250.134156.224.33.102
●NSjocelyn.ns.cloudflare.com2026-03-05 → 2026-03-24 · 3 obs
○ 2019-12-28 17:40:22
● 2026-03-05 23:03:58
● 2026-03-24 19:54:08
●NSmarty.ns.cloudflare.com2026-03-05 → 2026-03-24 · 3 obs
○ 2019-12-28 17:40:22
● 2026-03-05 23:03:58
● 2026-03-24 19:54:08
○NSns.chinaccnet.net2016-02-26 → 2016-06-21 · 5 obs
○ 2015-11-27 05:36:32
● 2016-02-26 21:52:50
● 2016-06-21 04:08:34
○ 2017-02-18 01:27:36
○ 2026-03-24 19:54:08
○NSns1.51dns.com2015-08-01 → 2015-08-01 · 3 obs
● 2015-08-01 15:57:52
○ 2015-11-27 05:36:32
○ 2026-03-24 19:54:08
○NSns1.chinaccnet.net2016-06-21 → 2016-06-21 · 4 obs
○ 2016-02-26 21:52:50
● 2016-06-21 04:08:34
○ 2017-02-18 01:27:36
○ 2026-03-24 19:54:08
○NSns2.51dns.com2015-08-01 → 2015-08-01 · 3 obs
● 2015-08-01 15:57:52
○ 2015-11-27 05:36:32
○ 2026-03-24 19:54:08
○NSns2.chinaccnet.net2016-06-21 → 2016-06-21 · 4 obs
○ 2016-02-26 21:52:50
● 2016-06-21 04:08:34
○ 2017-02-18 01:27:36
○ 2026-03-24 19:54:08
○NSns3.chinaccnet.net2016-06-21 → 2016-06-21 · 4 obs
○ 2016-02-26 21:52:50
● 2016-06-21 04:08:34
○ 2017-02-18 01:27:36
○ 2026-03-24 19:54:08
○NSns6.dnsdun.com2019-12-28 → 2019-12-28 · 4 obs
○ 2017-02-18 01:27:36
● 2019-12-28 17:40:22
○ 2026-03-05 23:03:58
○ 2026-03-24 19:54:08
○NSns6.dnsdun.net2019-12-28 → 2019-12-28 · 4 obs
○ 2017-02-18 01:27:36
● 2019-12-28 17:40:22
○ 2026-03-05 23:03:58
○ 2026-03-24 19:54:08
○A103.47.250.1342015-08-01 → 2015-08-01 · 3 obs
● 2015-08-01 15:57:52
○ 2015-11-27 05:36:32
○ 2026-03-24 19:54:08
●A104.21.68.2302026-03-05 → 2026-03-24 · 3 obs
○ 2019-12-28 17:40:22
● 2026-03-05 23:03:58
● 2026-03-24 19:54:08
○A156.224.33.1022019-12-28 → 2019-12-28 · 4 obs
○ 2015-11-27 05:36:32
● 2019-12-28 17:40:22
○ 2026-03-05 23:03:58
○ 2026-03-24 19:54:08
●A172.67.199.1302026-03-05 → 2026-03-24 · 3 obs
○ 2019-12-28 17:40:22
● 2026-03-05 23:03:58
● 2026-03-24 19:54:08
●A2606:4700:3032::6815:44e62026-03-05 → 2026-03-24 · 3 obs
○ 2019-12-28 17:40:22
● 2026-03-05 23:03:58
● 2026-03-24 19:54:08
●A2606:4700:3036::ac43:c7822026-03-05 → 2026-03-24 · 3 obs
○ 2019-12-28 17:40:22
● 2026-03-05 23:03:58
● 2026-03-24 19:54:08

🔍 DNS Trace

📋 Delegation Chain

ZoneNameserversGlue
coma.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net...-
21cnbook.commarty.ns.cloudflare.com, jocelyn.ns.cloudflare.com12 records

✅ Authoritative Response

Server:108.162.192.174

NS records: marty.ns.cloudflare.com, jocelyn.ns.cloudflare.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for 21cnbook.com (unsigned zone)

⏱️ Timing

Total: 160ms | Queries: -

📄 Records

TypeCountSample Data
A2172.67.199.130, 104.21.68.230
AAAA22606:4700:3036::ac43:c782, 2606:4700:3032::6815:44e6
NS2jocelyn.ns.cloudflare.com, marty.ns.cloudflare.com
HTTPS1{"priority":1,"target":".","alpn":["h3",
SOA1jocelyn.ns.cloudflare.com dns.cloudflare

📌 Glue Records Collected

Total: 12

Out-of-bailiwick: 12 (marty.ns.cloudflare.com, marty.ns.cloudflare.com, marty.ns.cloudflare.com...)

Analysis

IP Addresses

21cnbook.com points to four IP numbers: 2606:4700:3032::6815:44e6, 2606:4700:3036::ac43:c782, 104.21.68.230 and 172.67.199.130.

Other host names, for instance dybi.cn, mail.wizzair.sk, ravalement-de-facade-93.fr, cpif.org and www.cyylq.com share IP numbers with 21cnbook.com.

Name Servers

Delegation for 21cnbook.com rests with two name servers, jocelyn.ns.cloudflare.com and marty.ns.cloudflare.com.

21cnbook.com shares the same name server setup as other domains, including which-is-better.com, p-plus.cn, yisenfloor.com, trjckj.cn and jysyxx.cn.

21cnbook.com at least partially shares name servers with other domains, for instance asrlms.in, dipood-weerhoos.com, alquimiadigital.com.br, footbets365.com and bestradio.fm.

These name servers are commonly used with melissa.ns.cloudflare.com and justin.ns.cloudflare.com.

Host names with six IP numbers: jocelyn.ns.cloudflare.com points to: 2606:4700:50::adf5:3aae, 2803:f800:50::6ca2:c0ae, 2a06:98c1:50::ac40:20ae, 108.162.192.174, 172.64.32.174 and 173.245.58.174. marty.ns.cloudflare.com points to: 2606:4700:58::adf5:3bcc, 2803:f800:50::6ca2:c1cc, 2a06:98c1:50::ac40:21cc, 108.162.193.204, 172.64.33.204 and 173.245.59.204.