`linuxcourse.com`

DNSSEC	⚠️ Not signed
A	15.157.197.233^{🇨🇦 Amazon15.156.0.0/15 EC2 YUL prefix}
		PTR	`ec2-15-157-197-233.ca-central-1.compute.amazonaws.com`
A	16.52.221.26^{🇺🇸 Amazon16.52.0.0/16 EC2 YUL prefix}
NS	`singapore.power-dns.com` ⭐
NS	`ns1.power-dns.com`
		A	13.58.50.225^{🇺🇸 Amazon13.58.0.0/15 EC2 CMH prefix}
			PTR	`ec2-13-58-50-225.us-east-2.compute.amazonaws.com`
NS	`ns2.power-dns.com`
		A	188.166.142.159^{🇳🇱 DIGITALOCEAN188.166.140.0/22 DigitalOcean}
NS	`ns3.power-dns.com`
		A	139.59.220.175^{🇸🇬 DIGITALOCEAN139.59.220.0/22 DigitalOcean}
MX	`mx1.ewebdevelopment.com` ⭐
		A	159.203.54.48^{🇨🇦 DIGITALOCEAN159.203.52.0/22 DigitalOcean}
MX	`mx2.ewebdevelopment.com`⁽⁵⁾
		A	188.166.142.73^{🇳🇱 DIGITALOCEAN188.166.140.0/22 DigitalOcean}
TXT	`934c3bfaa10e7d053ed251a82e3f4a82d19da885`
TXT	`v=spf1 include:u2069692.wl.sendgrid.net -all`
TXT	`91f786e2661531d62a5e4bf8dc941c30c7391ed6`
TXT	`afternic-verification-VKoxaZkQawZ8VVht35n43c`
SOA	`singapore.power-dns.com`hostmaster@power-dns.com 2025-01-15 #1

`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=1778706911

Subdomains

nullmx.linuxcourse.com

Same first word

linuxcourse.nl

linuxcourse.com

Similar names

unisourcexl.net

linuxsource.com

linuxsource.de

sourcelinux.com

unisourcexl.com

linuxsource.nl

DNS History

24 records (8 active, 16 former)

○NSamsterdam.power-dns.com2020-01-09 → 2020-01-09 · 4 obs

○ 2016-02-12 08:11:12
● 2020-01-09 20:28:58
○ 2026-03-19 04:34:56
○ 2026-05-13 21:41:36

○NSip-172-26-1-146.us-east-2.compute.internal2026-03-19 → 2026-04-04 · 4 obs

○ 2020-01-09 20:28:58
● 2026-03-19 04:34:56
● 2026-04-04 08:27:38
○ 2026-05-13 21:41:36

○NSns1.hitfarm.com2008-03-20 → 2008-03-20 · 3 obs

● 2008-03-20 10:52:56
○ 2015-07-15 04:31:36
○ 2026-05-13 21:41:36

●NSns1.power-dns.com2015-07-15 → 2026-05-13 · 5 obs

○ 2008-03-20 10:52:56
● 2015-07-15 04:31:36
○ 2015-11-20 07:09:00
● 2016-02-12 08:11:12
● 2026-05-13 21:41:36

○NSns2.hitfarm.com2008-03-20 → 2008-03-20 · 3 obs

● 2008-03-20 10:52:56
○ 2015-07-15 04:31:36
○ 2026-05-13 21:41:36

●NSns2.power-dns.com2015-07-15 → 2026-05-13 · 6 obs

○ 2008-03-20 10:52:56
● 2015-07-15 04:31:36
● 2015-11-20 07:09:00
○ 2016-02-12 08:11:12
● 2020-01-09 20:28:58
● 2026-05-13 21:41:36

○NSns3.hitfarm.com2008-03-20 → 2008-03-20 · 3 obs

● 2008-03-20 10:52:56
○ 2015-07-15 04:31:36
○ 2026-05-13 21:41:36

●NSns3.power-dns.com2020-01-09 → 2026-05-13 · 3 obs

○ 2016-02-12 08:11:12
● 2020-01-09 20:28:58
● 2026-05-13 21:41:36

●NSsingapore.power-dns.com2026-05-13 → 2026-05-13 · 2 obs

○ 2026-04-04 08:27:38
● 2026-05-13 21:41:36

○MXmail.dovemail.com2015-07-15 → 2017-01-29 · 5 obs

○ 2008-03-20 10:52:56
● 2015-07-15 04:31:36
● 2017-01-29 13:17:00
○ 2020-01-09 20:28:58
○ 2026-05-13 21:41:36

●MXmx1.ewebdevelopment.com2020-01-09 → 2026-05-13 · 3 obs

○ 2017-01-29 13:17:00
● 2020-01-09 20:28:58
● 2026-05-13 21:41:36

●MXmx2.ewebdevelopment.com2020-01-09 → 2026-05-13 · 3 obs

○ 2017-01-29 13:17:00
● 2020-01-09 20:28:58
● 2026-05-13 21:41:36

○MXnullmx.linuxcourse.com2008-03-20 → 2008-03-20 · 3 obs

● 2008-03-20 10:52:56
○ 2015-07-15 04:31:36
○ 2026-05-13 21:41:36

●A15.157.197.2332026-05-13 → 2026-05-13 · 2 obs

○ 2026-04-04 08:27:38
● 2026-05-13 21:41:36

○A16.52.102.942026-03-19 → 2026-03-19 · 4 obs

○ 2020-01-09 20:28:58
● 2026-03-19 04:34:56
○ 2026-04-04 08:27:38
○ 2026-05-13 21:41:36

○A16.52.206.1002026-03-19 → 2026-03-19 · 4 obs

○ 2020-01-09 20:28:58
● 2026-03-19 04:34:56
○ 2026-04-04 08:27:38
○ 2026-05-13 21:41:36

●A16.52.221.262026-05-13 → 2026-05-13 · 2 obs

○ 2026-04-04 08:27:38
● 2026-05-13 21:41:36

○A16.54.19.742026-04-04 → 2026-04-04 · 3 obs

○ 2026-03-19 04:34:56
● 2026-04-04 08:27:38
○ 2026-05-13 21:41:36

○A16.54.9.1192026-04-04 → 2026-04-04 · 3 obs

○ 2026-03-19 04:34:56
● 2026-04-04 08:27:38
○ 2026-05-13 21:41:36

○A174.36.107.1302015-07-15 → 2017-01-29 · 5 obs

○ 2008-03-20 10:52:56
● 2015-07-15 04:31:36
● 2017-01-29 13:17:00
○ 2020-01-09 20:28:58
○ 2026-05-13 21:41:36

○A174.37.172.1622015-07-15 → 2015-07-15 · 4 obs

○ 2008-03-20 10:52:56
● 2015-07-15 04:31:36
○ 2026-03-19 04:34:56
○ 2026-05-13 21:41:36

○A217.68.70.692008-03-20 → 2008-03-20 · 3 obs

● 2008-03-20 10:52:56
○ 2015-07-15 04:31:36
○ 2026-05-13 21:41:36

○A52.60.233.32020-01-09 → 2020-01-09 · 4 obs

○ 2017-01-29 13:17:00
● 2020-01-09 20:28:58
○ 2026-03-19 04:34:56
○ 2026-05-13 21:41:36

○A99.79.96.1082020-01-09 → 2020-01-09 · 4 obs

○ 2017-01-29 13:17:00
● 2020-01-09 20:28:58
○ 2026-03-19 04:34:56
○ 2026-05-13 21:41:36

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
com	m.gtld-servers.net, d.gtld-servers.net, j.gtld-servers.net, h.gtld-servers.net...	-
linuxcourse.com	ns1.power-dns.com, ns2.power-dns.com, ns3.power-dns.com	3 records

✅ Authoritative Response

Server:139.59.220.175

NS records: ns1.power-dns.com, ns2.power-dns.com, ns3.power-dns.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for linuxcourse.com (unsigned zone)

⏱️ Timing

Total: 658ms | Queries: -

📄 Records

Type	Count	Sample Data
A	2	`16.52.221.26, 15.157.197.233`
NS	3	`ns2.power-dns.com, ns3.power-dns.com...`
MX	2	`mx2.ewebdevelopment.com (pri: 5), mx1.ewebdevelopment.com (pri: 1)`
TXT	4	`934c3bfaa10e7d053ed251a82e3f4a82d19da885, v=spf1 include:u2069692.wl.sendgrid.net ...`
SOA	1	`singapore.power-dns.com hostmaster.power`

📌 Glue Records Collected

Total: 3

Out-of-bailiwick: 3 (ns1.power-dns.com, ns2.power-dns.com, ns3.power-dns.com)

Analysis

Hierarchy

linuxcourse.com is the parent of nullmx.linuxcourse.com.

IP Addresses

linuxcourse.com resolves to two IP numbers: 15.157.197.233 and 16.52.221.26.

other host names including weinter.com, rosna.com, best-mail.com, rose-shop.com and koshky.com share IP numbers with linuxcourse.com.

Name Servers

linuxcourse.com is delegated to four name servers: ns1.power-dns.com, ns2.power-dns.com, ns3.power-dns.com and singapore.power-dns.com.

linuxcourse.com at least partially shares name servers with other domains, for instance explain-it.com, africanitems.com, pkwe.com, scclan.com and kurana.com.

These name servers are commonly used alongside ip-172-26-1-146.us-east-2.compute.internal and amsterdam.power-dns.com.

Host names with one IP number: ns1.power-dns.com points to 13.58.50.225; ns2.power-dns.com points to 188.166.142.159; ns3.power-dns.com points to 139.59.220.175.

Mail Servers

Two mail servers handle linuxcourse.com: mx1.ewebdevelopment.com and mx2.ewebdevelopment.com.

linuxcourse.com shares the same mail server setup as other domains, for instance hasdia.com, tasana.com, wocia.com, mx0.grocko.com and pulseclub.com.

Host names with one IP number:

mx1.ewebdevelopment.com points to 159.203.54.48

mx2.ewebdevelopment.com points to 188.166.142.73

linuxcourse.com - robtex.com

linuxcourse.com

com

Subdomains

Same first word

Similar names

DNS History

🔍 DNS Trace

📋 Delegation Chain

✅ Authoritative Response

🔒 DNSSEC Status

⏱️ Timing

📄 Records

📌 Glue Records Collected

Analysis

Hierarchy

IP Addresses

Name Servers

Mail Servers

`linuxcourse.com`

`com`