21study.com - robtex.com

🛡️Domain Reputation CheckBlocklist, phishing & malware status→

21study.com

DNSSEC⚠️ Not signed
A156.237.200.98🇭🇰 HDHK156.237.192.0/20 Proxy-registered route object
NSv1s1.xundns.com ⭐
A2409:8c44:1b00:601:1:1110:609:6027🇨🇳 CHINAMOBILE-CN2409:8c44:1b00::/48 CMI (Customer Route)
A2604:86c0:5001:11::2659:466b🇺🇸 AS630232604:86c0:5000::/36 GTHOST-SEA
A38.89.70.107🇺🇸 AS6302338.89.70.0/24 Route Registered for Cogent Communications Customer - GlobalTelehost Corp
PTR107-70-89-38.clients.gthost.com
A42.240.163.163🇨🇳 CHINANET-Guangdong-GuangZhou-IDC42.240.160.0/20 Guangzhou IDC of ChinaUnicom
A111.6.96.27🇨🇳 CHINAMOBILE-CN111.6.96.0/21 CMI (Customer Route)
NSv1s2.xundns.com
A2408:8621:0:42:e401:813:0:25🇨🇳 CHINA169-Backbone2408:8621::/32 China Unicom B811&A1218, China Unicom No.21, Jin-Rong Street
A2408:8722:1801:10:4:611:6303:181🇨🇳 CHINA169-Backbone2408:8722::/32 China Unicom B811&A1218, China Unicom No.21, Jin-Rong Street
A2604:86c0:6001:8::a9c5:8e51🇺🇸 AS630232604:86c0:6000::/36 GTHOST-SCL
A61.163.30.181🇨🇳 CHINA169-Backbone61.163.0.0/16 CNC Group CHINA169 Henan Province Network
PTRhn.ly.kd.adsl
A122.114.39.7🇨🇳 CHINA169-Backbone122.114.0.0/16 route of Chinaunicomroute of Chinaunicom
A169.197.142.81🇺🇸 AS63023169.197.142.0/24 GlobalTeleHost
PTR81-142-197-169.clients.gthost.com
SOAv1s1.xundns.comnsadmin@xundns.com serial=431016

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=1794556026

Same first word

21study.com
21study.net

Similar names

study12.com
12study.com
12study.cn
study21.ru
study21.cz
study12.xyz
study21.com
study21.org
study21.net
study21.co.kr
study21.cn

Previous names

21sttruck.com
21sttv.com
21stu.com
21stuart.com
21stuberpng.com
21stud.com
21studgaming.com
21studio.com
21studio12.com
21studiodesign.com
21studios.com
21studiosbollate.com
21studiosphotography.com
21studpoker.com
21studs.com

Next names

21studyo.com
21stuff.com
21stuffs.com
21stunden.com
21stunion.com
21stuniversalentertainment.com
21sturban.com
21stusa.com
21stuw.com
21stuwhworlds.com
21stv.com
21stva.com
21stvapes.com
21stvapor.com

DNS History

11 records (3 active, 8 former)

20162017201820192020202120222023202420252026NSv1s1.xundns.comv1s2.xundns.comdns1.name-services.comdns2.name-services.comdns3.name-services.comdns4.name-services.comdns5.name-services.comMXp.nsm.ctmail.comA156.237.200.98122.10.8.10969.64.147.243
○NSdns1.name-services.com2015-05-27 → 2016-04-21 · 4 obs
● 2015-05-27 12:46:00
● 2016-04-21 09:38:50
○ 2017-04-02 06:23:44
○ 2026-11-13 08:26:32
○NSdns2.name-services.com2015-05-27 → 2016-04-21 · 4 obs
● 2015-05-27 12:46:00
● 2016-04-21 09:38:50
○ 2017-04-02 06:23:44
○ 2026-11-13 08:26:32
○NSdns3.name-services.com2015-05-27 → 2016-04-21 · 4 obs
● 2015-05-27 12:46:00
● 2016-04-21 09:38:50
○ 2017-04-02 06:23:44
○ 2026-11-13 08:26:32
○NSdns4.name-services.com2015-05-27 → 2016-04-21 · 4 obs
● 2015-05-27 12:46:00
● 2016-04-21 09:38:50
○ 2017-04-02 06:23:44
○ 2026-11-13 08:26:32
○NSdns5.name-services.com2015-05-27 → 2016-04-21 · 4 obs
● 2015-05-27 12:46:00
● 2016-04-21 09:38:50
○ 2017-04-02 06:23:44
○ 2026-11-13 08:26:32
●NSv1s1.xundns.com2017-04-02 → 2026-11-13 · 5 obs
○ 2016-04-21 09:38:50
● 2017-04-02 06:23:44
○ 2020-03-26 23:18:34
● 2026-09-22 09:13:10
● 2026-11-13 08:26:32
●NSv1s2.xundns.com2017-04-02 → 2026-11-13 · 5 obs
○ 2016-04-21 09:38:50
● 2017-04-02 06:23:44
○ 2020-03-26 23:18:34
● 2026-09-22 09:13:10
● 2026-11-13 08:26:32
○MXp.nsm.ctmail.com2015-05-27 → 2016-04-21 · 4 obs
● 2015-05-27 12:46:00
● 2016-04-21 09:38:50
○ 2017-04-02 06:23:44
○ 2026-11-13 08:26:32
○A122.10.8.1092017-04-02 → 2017-04-02 · 4 obs
○ 2016-04-21 09:38:50
● 2017-04-02 06:23:44
○ 2020-03-26 23:18:34
○ 2026-11-13 08:26:32
●A156.237.200.982020-03-26 → 2026-11-13 · 3 obs
○ 2017-04-02 06:23:44
● 2020-03-26 23:18:34
● 2026-11-13 08:26:32
○A69.64.147.2432015-05-27 → 2016-04-21 · 4 obs
● 2015-05-27 12:46:00
● 2016-04-21 09:38:50
○ 2017-04-02 06:23:44
○ 2026-11-13 08:26:32

🔍 DNS Trace

📋 Delegation Chain

ZoneNameserversGlue
coma.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net...-
21study.comv1s1.xundns.com, v1s2.xundns.com11 records

✅ Authoritative Response

Server:111.6.96.27

NS records: v1s1.xundns.com, v1s2.xundns.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

Root DNSKEY fetch failed: Error: connect EADDRNOTAVAIL 198.41.0.4:53 - Local (0.0.0.0:0)

⏱️ Timing

Total: 3783ms | Queries: -

📄 Records

TypeCountSample Data
A1156.237.200.98
NS2v1s2.xundns.com, v1s1.xundns.com
SOA1v1s1.xundns.com nsadmin.xundns.com

📌 Glue Records Collected

Total: 11

Out-of-bailiwick: 11 (v1s1.xundns.com, v1s1.xundns.com, v1s1.xundns.com...)

Analysis

IP Addresses

21study.com directs to one IP number, which is 156.237.200.98.

Among the host names that share IP numbers with 21study.com are jisudi.com, asp8.com, www.qin.info and two others.

Name Servers

DNS delegation for 21study.com points to two name servers: v1s1.xundns.com and v1s2.xundns.com.

21study.com has the same name server delegation as a number of other domains, such as 303100.com, avtt259vip.com, 36966b.com and two more.

At least some of 21study.com's name servers are shared with other domains, for example xd75914.cc, 65366623.com, 914072.cc and two more.

These name servers tend to be deployed in combination with the name servers n1.xundns.com and n2.xundns.com.

Host names resolving to 6 IP numbers:

v1s2.xundns.com has IP addresses 61.163.30.181, 122.114.39.7 and 169.197.142.81, plus 3 other.

Hostnames that point to five IP numbers:

v1s1.xundns.com directs to 38.89.70.107, 42.240.163.163, 111.6.96.27 and two other IP addresses.