`21stcsi.com`

DNSSEC	⚠️ Not signed
A	3.33.251.168^{🇺🇸 Amazon3.33.240.0/20}
		PTR	`aec037177372cc6cd.awsglobalaccelerator.com`
A	15.197.225.128^{🇺🇸 Amazon15.197.224.0/20}
NS	`ns75.domaincontrol.com` ⭐
		A	2603:5:21b4::30^{🇺🇸 GODADDY-DNS2603:5:21b0::/44}
			PTR	`ns75.domaincontrol.com`
		A	97.74.107.48^{🇺🇸 GODADDY-DNS97.74.106.0/23}
			PTR	`ns75.domaincontrol.com`
NS	`ns76.domaincontrol.com`
		A	2603:5:22b4::30^{🇺🇸 GODADDY-DNS2603:5:22b0::/44}
			PTR	`ns76.domaincontrol.com`
		A	173.201.75.48^{🇺🇸 GODADDY-DNS173.201.74.0/23}
			PTR	`ns76.domaincontrol.com`
MX	`21stcsi.com.1.0001.arsmtp.com` ⭐
		A	8.31.233.84^{🇺🇸 APPRI-18.31.233.0/24 AppRiver, LLC 1101 Gulf Breeze Parkway Gulf Breeze, FL 32561 US}
			PTR	`server228.appriver.com`
MX	`21stcsi.com.2.0001.arsmtp.com`⁽²⁰⁾
		A	8.19.118.171^{🇺🇸 AS133808.19.118.0/24 AppRiver, LLC 1101 Gulf Breeze Parkway Gulf Breeze, FL 32561 US}
			PTR	`server229.appriver.com`
TXT	`MS=4D4C0CB55A491D6B2FDE17BF7E4DE90B7FF8C5FC`
TXT	`MS=ms89687458`
TXT	`v=spf1 include:spf.protection.outlook.com -all`
SOA	`ns75.domaincontrol.com`dns@jomax.net 2026-03-02 #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=1774402057

Subdomains

mx.21stcsi.com

Same first word

21stcsi.com

DNS History

9 records (6 active, 3 former)

●NSns75.domaincontrol.com2015-08-28 → 2026-03-25 · 2 obs

● 2015-08-28 18:55:20
● 2026-03-25 01:33:40

●NSns76.domaincontrol.com2015-08-28 → 2026-03-25 · 2 obs

● 2015-08-28 18:55:20
● 2026-03-25 01:33:40

●MX21stcsi.com.1.0001.arsmtp.com2016-04-15 → 2026-03-25 · 3 obs

○ 2016-01-26 15:16:30
● 2016-04-15 02:25:32
● 2026-03-25 01:33:40

●MX21stcsi.com.2.0001.arsmtp.com2016-04-15 → 2026-03-25 · 3 obs

○ 2016-01-26 15:16:30
● 2016-04-15 02:25:32
● 2026-03-25 01:33:40

○MXmx.21stcsi.com2015-08-28 → 2015-09-30 · 4 obs

● 2015-08-28 18:55:20
● 2015-09-30 03:32:24
○ 2015-10-12 00:25:36
○ 2026-03-25 01:33:40

○MXmx.intechgratesystems.com2015-10-12 → 2016-01-26 · 5 obs

○ 2015-09-30 03:32:24
● 2015-10-12 00:25:36
● 2016-01-26 15:16:30
○ 2016-04-15 02:25:32
○ 2026-03-25 01:33:40

●A15.197.225.1282026-02-19 → 2026-03-25 · 3 obs

○ 2017-09-11 07:13:18
● 2026-02-19 09:04:10
● 2026-03-25 01:33:40

●A3.33.251.1682026-02-19 → 2026-03-25 · 3 obs

○ 2017-09-11 07:13:18
● 2026-02-19 09:04:10
● 2026-03-25 01:33:40

○A50.63.202.42015-08-28 → 2017-09-11 · 4 obs

● 2015-08-28 18:55:20
● 2017-09-11 07:13:18
○ 2026-02-19 09:04:10
○ 2026-03-25 01:33:40

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
com	k.gtld-servers.net, j.gtld-servers.net, l.gtld-servers.net, d.gtld-servers.net...	-
21stcsi.com	ns75.domaincontrol.com, ns76.domaincontrol.com	4 records

✅ Authoritative Response

Server:97.74.107.48

NS records: ns75.domaincontrol.com, ns76.domaincontrol.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

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

⏱️ Timing

Total: 162ms | Queries: -

📄 Records

Type	Count	Sample Data
A	2	`15.197.225.128, 3.33.251.168`
NS	2	`ns75.domaincontrol.com, ns76.domaincontrol.com`
MX	2	`21stcsi.com.1.0001.arsmtp.com (pri: 10), 21stcsi.com.2.0001.arsmtp.com (pri: 20)`
TXT	3	`MS=4D4C0CB55A491D6B2FDE17BF7E4DE90B7FF8C, MS=ms89687458...`
SOA	1	`ns75.domaincontrol.com dns.jomax.net`

📌 Glue Records Collected

Total: 4

Out-of-bailiwick: 4 (ns75.domaincontrol.com, ns75.domaincontrol.com, ns76.domaincontrol.com...)

Analysis

Hierarchy

21stcsi.com is the parent of mx.21stcsi.com.

IP Addresses

21stcsi.com resolves to two IP numbers: 3.33.251.168 and 15.197.225.128.

other host names including metalremediation.com, watervisions.ca, literacynest.com, aoaministry.com and excipient.com share IP numbers with 21stcsi.com.

Name Servers

21stcsi.com is delegated to two name servers ns75.domaincontrol.com and ns76.domaincontrol.com.

21stcsi.com shares the same name server setup as other domains, for instance beatspeat.com, prism-enclosures.com, ws6.com, buildersflooringshowroom.com and marketingnightmares.com.

21stcsi.com at least partially shares name servers with other domains, for instance prestigelinens.com.

Host names with two IP numbers:

The host name ns75.domaincontrol.com points to 2603:5:21b4::30 and 97.74.107.48; the host name ns76.domaincontrol.com points to 2603:5:22b4::30 and 173.201.75.48.

Mail Servers

Two mail servers handle 21stcsi.com: 21stcsi.com.1.0001.arsmtp.com and 21stcsi.com.2.0001.arsmtp.com.

Host names with one IP number:

21stcsi.com.1.0001.arsmtp.com points to 8.31.233.84

21stcsi.com.2.0001.arsmtp.com points to 8.19.118.171

21stcsi.com - robtex.com

21stcsi.com

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