`common-systems.com`

DNSSEC	⚠️ Not signed
A	2001:1568::14^{🇨🇿 WEB4U2001:1568::/33}
		PTR	`php7.web4u.cz`
A	81.91.86.14^{🇨🇿 WEB4U81.91.80.0/21}
NS	`ns2.web4u.cz` ⭐
		A	2a02:a40:100:28ff::12^{🇨🇿 BlueTone-AS2a02:a40::/32 Ceske Radiokomunikace, a.s.}
			PTR	`ns2.web4u.cz`
		A	85.207.53.12^{🇨🇿 BlueTone-AS85.207.0.0/16 BlueTone-CRa-CZ Fourth address block}
			PTR	`ns2.web4u.cz`
NS	`ns.web4u.cz`
		A	2001:1568:fd::241^{🇨🇿 WEB4U2001:1568::/33}
			PTR	`ns.web4u.cz`
		A	185.14.224.241^{🇨🇿 WEB4U185.14.224.0/23}
			PTR	`ns.web4u.cz`
MX	`mx1.mailchannels.net` ⭐ 🔒
		A	18.236.29.166^{🇺🇸 Amazon18.236.0.0/15 EC2 PDX prefix}
			PTR	`ec2-18-236-29-166.us-west-2.compute.amazonaws.com`
MX	`mx2.mailchannels.net` ⭐ 🔒
		A	52.38.143.159^{🇺🇸 Amazon52.36.0.0/14 EC2 PDX prefix}
			PTR	`ec2-52-38-143-159.us-west-2.compute.amazonaws.com`
TXT	`v=spf1 include:_spf.web4u.cz ~all`
SOA	`ns.web4u.cz`admin@web4u.cz 2025-05-05 #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=1771291435

Similar names

commons-system.com

DNS History

7 records (6 active, 1 former)

●NSns.web4u.cz2018-05-15 → 2026-03-14 · 2 obs

● 2018-05-15 14:51:34
● 2026-03-14 10:12:00

●NSns2.web4u.cz2018-05-15 → 2026-03-14 · 2 obs

● 2018-05-15 14:51:34
● 2026-03-14 10:12:00

○MXmail.common-systems.com2018-05-15 → 2018-05-15 · 2 obs

● 2018-05-15 14:51:34
○ 2026-03-14 10:12:00

●MXmx1.mailchannels.net2026-03-14 → 2026-03-14 · 2 obs

○ 2018-05-15 14:51:34
● 2026-03-14 10:12:00

●MXmx2.mailchannels.net2026-03-14 → 2026-03-14 · 2 obs

○ 2018-05-15 14:51:34
● 2026-03-14 10:12:00

●A2001:1568::142018-05-15 → 2026-03-14 · 2 obs

● 2018-05-15 14:51:34
● 2026-03-14 10:12:00

●A81.91.86.142018-05-15 → 2026-03-14 · 2 obs

● 2018-05-15 14:51:34
● 2026-03-14 10:12:00

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
com	a.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net...	-
common-systems.com	ns.web4u.cz, ns2.web4u.cz	-

✅ Authoritative Response

Server: 185.14.224.241

NS records: ns.web4u.cz, ns2.web4u.cz

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for common-systems.com (unsigned zone)

⏱️ Timing

Total: 794ms | Queries: -

📄 Records

Type	Count	Sample Data
A	1	`81.91.86.14`
AAAA	1	`2001:1568::14`
NS	2	`ns.web4u.cz, ns2.web4u.cz`
MX	2	`mx1.mailchannels.net (pri: 10), mx2.mailchannels.net (pri: 10)`
TXT	1	`v=spf1 include:_spf.web4u.cz ~all`
SOA	1	`ns.web4u.cz admin.web4u.cz`

Analysis

IP Addresses

common-systems.com resolves to two IP numbers: 2001:1568::14 and 81.91.86.14.

other host names including 134m105.server4u.cz, wuch.pl, kubatronik.de, www.kumbaldekor.cz and vs110.server4u.cz share IP numbers with common-systems.com.

Name Servers

common-systems.com is delegated to two name servers ns2.web4u.cz and ns.web4u.cz.

common-systems.com shares the same name server setup as other domains, for instance cordiant.cz, castkaslovy.eu, spdrazice.cz, goldia.cz and dka.cz.

Host names with two IP numbers:

The host name ns2.web4u.cz points to 2a02:a40:100:28ff::12 and 85.207.53.12; the host name ns.web4u.cz points to 2001:1568:fd::241 and 185.14.224.241.

Mail Servers

Two mail servers handle common-systems.com: mx1.mailchannels.net and mx2.mailchannels.net.

common-systems.com shares the same mail server setup as other domains, for instance emprint.fr, amandatelford.com, aquafarm.com, weeb.cl and aldocherres.com.

common-systems.com shares at least some mail servers with other domains, including burkegilmanbrewing.com, lund.sap.se, taktiform.se and consultinglegacy.com.

Host names with one IP number:

mx1.mailchannels.net points to 18.236.29.166

mx2.mailchannels.net points to 52.38.143.159

common-systems.com - robtex.com