`u21.com`

DNSSEC	⚠️ Not signed
A	208.98.43.99^{🇺🇸 SHARKTECH-1208.98.43.0/24}
		PTR	`node-208-98-43-99.reverse.x4b.me`
NS	`www.u21.com` ⭐
		A	208.98.43.33^{🇺🇸 SHARKTECH-1208.98.43.0/24}
NS	`ns1.4.cn` ⚠️ Not in zone NS records
		A	107.167.27.66^{🇺🇸 SHARKTECH-1107.167.27.0/24 CMI (Customer Route)}
NS	`ns2.4.cn` ⚠️ Not in zone NS records
		A	208.98.43.66^{🇺🇸 SHARKTECH-1208.98.43.0/24}
			PTR	`jensenstilbud.com`
SOA	`www.u21.com`u21@com 2008-08-03 #0

`com`

	DNSSEC	🔒 Signed (DS record present)
	NS	`a.gtld-servers.net` ⭐
	NS	`b.gtld-servers.net`
	NS	`c.gtld-servers.net`
	NS	`d.gtld-servers.net`
	NS	`e.gtld-servers.net`
	NS	`f.gtld-servers.net`
	NS	`g.gtld-servers.net`
	NS	`h.gtld-servers.net`
	NS	`i.gtld-servers.net`
	NS	`j.gtld-servers.net`
	NS	`k.gtld-servers.net`
	NS	`l.gtld-servers.net`
	NS	`m.gtld-servers.net`
	SOA	`a.gtld-servers.net`nstld@verisign-grs.com serial=1783200876

Subdomains

www.u21.com

Same first word

u21.org.cn

u21.ru

u21.mobi

u21.ca

u21.de

u21.com

u21.org.hk

u21.eu

u21.co

u21.nu

u21.ch

u21.net

u21.com.cn

u21.tv

u21.nl

u21.hk

u21.pl

u21.org

Similar names

1u2.net

1u2.com

u12.com.br

12u.de

2u1.cc

12u.nl

2u1.com

12u.pl

12u.biz

u12.eu

12u.com

12u.co.nz

12u.eu

u12.com

u12.ru

21u.org

1u2.de

12u.net

12u.be

21u.com

1u2.ru

12u.org

u12.pl

u12.org

u12.net

21u.cn

2u1.de

12u.dk

u12.com.cn

u12.nl

u12.de

21u.ru

12u.ru

DNS History

20 records (4 active, 16 former)

○NSdns1.iidns.com2015-07-09 → 2016-06-18 · 6 obs

● 2015-07-09 20:56:00
○ 2015-11-25 00:02:36
● 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○NSdns2.iidns.com2015-07-09 → 2016-06-18 · 6 obs

● 2015-07-09 20:56:00
○ 2015-11-25 00:02:36
● 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○NSdns3.iidns.com2015-07-09 → 2016-06-18 · 6 obs

● 2015-07-09 20:56:00
○ 2015-11-25 00:02:36
● 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○NSdns4.iidns.com2015-07-09 → 2016-06-18 · 6 obs

● 2015-07-09 20:56:00
○ 2015-11-25 00:02:36
● 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○NSdns5.iidns.com2015-07-09 → 2016-06-18 · 6 obs

● 2015-07-09 20:56:00
○ 2015-11-25 00:02:36
● 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○NSdns6.iidns.com2015-07-09 → 2016-06-18 · 6 obs

● 2015-07-09 20:56:00
○ 2015-11-25 00:02:36
● 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○NSf1g1ns1.dnspod.net2015-11-25 → 2015-11-25 · 4 obs

○ 2015-07-09 20:56:00
● 2015-11-25 00:02:36
○ 2016-02-29 22:03:10
○ 2026-07-04 21:46:16

○NSf1g1ns2.dnspod.net2015-11-25 → 2015-11-25 · 4 obs

○ 2015-07-09 20:56:00
● 2015-11-25 00:02:36
○ 2016-02-29 22:03:10
○ 2026-07-04 21:46:16

●NSns1.4.cn2026-06-22 → 2026-07-04 · 3 obs

○ 2018-07-06 20:24:54
● 2026-06-22 19:24:54
● 2026-07-04 21:46:16

●NSns2.4.cn2026-06-22 → 2026-07-04 · 3 obs

○ 2018-07-06 20:24:54
● 2026-06-22 19:24:54
● 2026-07-04 21:46:16

●NSwww.u21.com2018-07-06 → 2026-07-04 · 3 obs

○ 2016-06-18 19:59:58
● 2018-07-06 20:24:54
● 2026-07-04 21:46:16

○A107.167.19.722016-02-29 → 2016-02-29 · 3 obs

● 2016-02-29 22:03:10
○ 2016-06-18 19:59:58
○ 2026-07-04 21:46:16

○A107.167.19.732016-02-29 → 2016-02-29 · 3 obs

● 2016-02-29 22:03:10
○ 2016-06-18 19:59:58
○ 2026-07-04 21:46:16

○A107.167.19.742016-06-18 → 2016-06-18 · 4 obs

○ 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○A107.167.19.752016-06-18 → 2016-06-18 · 4 obs

○ 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○A208.98.40.2072026-06-22 → 2026-06-22 · 4 obs

○ 2018-07-06 20:24:54
● 2026-06-22 19:24:54
○ 2026-06-23 20:35:48
○ 2026-07-04 21:46:16

○A208.98.43.742026-06-23 → 2026-06-23 · 4 obs

○ 2026-06-22 19:24:54
● 2026-06-23 20:35:48
○ 2026-07-04 21:46:14
○ 2026-07-04 21:46:16

●A208.98.43.992026-07-04 → 2026-07-04 · 3 obs

○ 2026-06-23 20:35:48
● 2026-07-04 21:46:14
● 2026-07-04 21:46:16

○CNAMEcs.ename.net2016-02-29 → 2016-06-18 · 4 obs

● 2016-02-29 22:03:10
● 2016-06-18 19:59:58
○ 2018-07-06 20:24:54
○ 2026-07-04 21:46:16

○CNAMEu.dcoin.co2018-07-06 → 2018-07-06 · 4 obs

○ 2016-06-18 19:59:58
● 2018-07-06 20:24:54
○ 2026-06-22 19:24:54
○ 2026-07-04 21:46:16

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
com	i.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net, m.gtld-servers.net...	-
u21.com	ns1.4.cn, ns2.4.cn	-

✅ Authoritative Response

Server:208.98.43.66

NS records: ns1.4.cn, ns2.4.cn

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for u21.com (unsigned zone)

⏱️ Timing

Total: 1401ms | Queries: -

📄 Records

Type	Count	Sample Data
A	1	`208.98.40.228`
SOA	1	`www.u21.com u21.com`

Analysis

Hierarchy

The domain www.u21.com falls under the parent u21.com.

IP Addresses

u21.com resolves to one IP address: 208.98.43.99.

www.225s.com, www.5912.cc, www.www.gaoyn.com and two other host names share IP numbers with u21.com.

Name Servers

u21.com is delegated to three name servers: ns1.4.cn, ns2.4.cn and www.u21.com.

At least some of u21.com's name servers are shared with other domains, for example baobaoyun.com, qiqiwang.com, qhkszs.com and two more.

These name servers are often deployed together with the name servers ns3.goldenname.com, ns4.goldenname.com, www.baobaoyun.com and www.qiqiwang.com.

ns1.4.cn, ns2.4.cn and www.u21.com each resolve to a single IP address: ns1.4.cn resolves to 107.167.27.66, ns2.4.cn resolves to 208.98.43.66 and www.u21.com resolves to 208.98.43.33.

u21.com - robtex.com

u21.com

com

Subdomains

Same first word

Similar names

DNS History

🔍 DNS Trace

📋 Delegation Chain

✅ Authoritative Response

🔒 DNSSEC Status

⏱️ Timing

📄 Records

Analysis

Hierarchy

IP Addresses

Name Servers

`u21.com`

`com`