courses.com - dns.ninja

`courses.com`

DNSSEC	⚠️ Not signed
A	2606:4700:3032::ac43:8856^{🇺🇸 Cloudflare2606:4700:3032::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	2606:4700:3033::6815:50fa^{🇺🇸 Cloudflare2606:4700:3033::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	104.21.80.250^{Cloudflare104.21.80.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
A	172.67.136.86^{🇺🇸 Cloudflare172.67.128.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US} ✓ In HTTPS hints
NS	`clarissa.ns.cloudflare.com` ⭐
		A	2606:4700:50::a29f:267b^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`clarissa.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c27b^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`clarissa.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:227b^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`clarissa.ns.cloudflare.com`
		A	108.162.194.123^{🇺🇸 Cloudflare108.162.194.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`clarissa.ns.cloudflare.com`
		A	162.159.38.123^{Cloudflare162.159.32.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`clarissa.ns.cloudflare.com`
		A	172.64.34.123^{🇺🇸 Cloudflare172.64.34.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`clarissa.ns.cloudflare.com`
NS	`colin.ns.cloudflare.com`
		A	2606:4700:58::a29f:2c4b^{🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`colin.ns.cloudflare.com`
		A	2803:f800:50::6ca2:c34b^{🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L}
			PTR	`colin.ns.cloudflare.com`
		A	2a06:98c1:50::ac40:234b^{🇺🇸 Cloudflare2a06:98c1:50::/45}
			PTR	`colin.ns.cloudflare.com`
		A	108.162.195.75^{🇺🇸 Cloudflare108.162.195.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`colin.ns.cloudflare.com`
		A	162.159.44.75^{Cloudflare162.159.32.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`colin.ns.cloudflare.com`
		A	172.64.35.75^{🇺🇸 Cloudflare172.64.35.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US}
			PTR	`colin.ns.cloudflare.com`
MX	`mx1.cloudhosting.net` ⭐
		A	185.53.56.44^{🇬🇧 KRYSTAL185.53.56.0/22}
			PTR	`mx1.strikemail.co.uk`
		A	185.53.56.46^{🇬🇧 KRYSTAL185.53.56.0/22}
			PTR	`mx1.strikemail.co.uk`
MX	`mx2.cloudhosting.net`⁽²⁰⁾
		A	185.53.56.45^{🇬🇧 KRYSTAL185.53.56.0/22}
			PTR	`mx2.strikemail.co.uk`
		A	185.53.56.47^{🇬🇧 KRYSTAL185.53.56.0/22}
TXT	`v=spf1 a:mail.courses.com include:spf.ahasend.com include:relay.mailchannels....`
HTTPS	HTTP/3, HTTP/2 ✓ hints match
		IPv4 hints	104.21.80.250, 172.67.136.86
		IPv6 hints	2606:4700:3032::ac43:8856, 2606:4700:3033::6815:50fa
		ECH	X25519, HKDF-SHA256 + AES-128-GCM draft, id=36, name=cloudflare-ech.com
SOA	`clarissa.ns.cloudflare.com`dns@cloudflare.com serial=2406612565

`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=1783985027

Subdomains

smtp.courses.com

39428.courses.com

www.courses.com

Same first word

courses.company

courses.net.au

courses.de

courses.es

courses.ie

courses.be

courses.cz

courses.durban

courses.asia

courses

courses.ge

courses.technology

courses.yolasite.com

courses.su

courses.camp

courses.istanbul

courses.com

courses.casino

courses.zone

courses.net.ua

courses.work

courses.edu

courses.at

courses.me

courses.ca

courses.wiki

courses.today

courses.school

courses.com.au

courses.tv

courses.forum

courses.courses

courses.ch

courses.world

courses.co

courses.com.ph

courses.plus

courses.ro

courses.neustar

courses.us

courses.nl

courses.store

courses.biz

courses.it

courses.ae

courses.media

courses.education

courses.se

courses.cn

courses.org

courses.dk

courses.bio

courses.agency

courses.ist

courses.guru

courses.kz

courses.eu

courses.co.uk

courses.bg

courses.kg

courses.capetown

Similar names

sources.hu

cousers.com

sources.co.uk

sources.pl

ecursos.es

croesus.com.tw

croesus.com

sorescu.eu

ecursos.herokuapp.com

roussec.kasserver.com

sources.com.sa

sources.download

sources.news

rescous.com

sources.biz

ecursos.cl

croesus.eu

secours.nl

resusco.com

sucrose.de

secours.eu

seurcos.click

ecursos.com.br

croesus.tv

cosuser.com

croesus.gr

scoreus.com

cosreus.cat

sources.debian.net

escours.eu

sources.org

suresco.com

secorus.com

crouses.com

suscore.com

croseus.com

coresus.com

sources.co

croesus.nl

securos.co

sources.de

croesus.cn

scourse.de

escuros.com

sources.at

securos.ru

securos.de

croesus.org

securos.net

securos.co.uk

ssource.com.sg

ussocer.com

sources.net

crousse.com.ar

sources.ws

ecoruss.ru

securos.com

secours.ca

sucrose.hatenablog.com

sources.it

croesus.ru

scouser.dk

croesus.it

securos.se

croesus.com.my

sources.dk

sources.cn

sources.ru

secours.net

sources.nl

sources.eu

sosecur.com

secours.gov.gn

securos.org.ua

scouser.net

sources.network

scoresu.me

secours.info

sucrose.com

sceuros.com

scseuro.de

ssource.com

sources.net.ar

croesus.de

sources.in

sources.com

croesus.ca

sucesor.com

croesus.fr

sources.ca

scouser.com

suresco.es

sources.fr

secosur.com.mx

croesus.net

sources.ch

coursse.com

DNS History

23 records (8 active, 15 former)

●NSclarissa.ns.cloudflare.com2026-02-14 → 2026-07-13 · 3 obs

○ 2017-04-01 09:06:08
● 2026-02-14 16:50:58
● 2026-07-13 23:46:54

●NScolin.ns.cloudflare.com2026-02-14 → 2026-07-13 · 3 obs

○ 2017-04-01 09:06:08
● 2026-02-14 16:50:58
● 2026-07-13 23:46:54

○NSns1.courserver.com2015-08-04 → 2016-04-10 · 4 obs

● 2015-08-04 12:44:04
● 2016-04-10 18:17:10
○ 2017-04-01 09:06:08
○ 2026-07-13 23:46:54

○NSns10.dnsmadeeasy.com2015-08-04 → 2016-04-10 · 4 obs

● 2015-08-04 12:44:04
● 2016-04-10 18:17:10
○ 2017-04-01 09:06:08
○ 2026-07-13 23:46:54

○NSns2.courserver.com2015-08-04 → 2016-04-10 · 4 obs

● 2015-08-04 12:44:04
● 2016-04-10 18:17:10
○ 2017-04-01 09:06:08
○ 2026-07-13 23:46:54

○NSns3.courserver.com2015-08-04 → 2016-04-10 · 4 obs

● 2015-08-04 12:44:04
● 2016-04-10 18:17:10
○ 2017-04-01 09:06:08
○ 2026-07-13 23:46:54

○NSns4.courserver.com2015-08-04 → 2016-04-10 · 4 obs

● 2015-08-04 12:44:04
● 2016-04-10 18:17:10
○ 2017-04-01 09:06:08
○ 2026-07-13 23:46:54

○NSns5.courserver.com2015-08-04 → 2016-04-10 · 4 obs

● 2015-08-04 12:44:04
● 2016-04-10 18:17:10
○ 2017-04-01 09:06:08
○ 2026-07-13 23:46:54

○NSns51.domaincontrol.com2017-04-01 → 2017-04-01 · 4 obs

○ 2016-04-10 18:17:10
● 2017-04-01 09:06:08
○ 2026-02-14 16:50:58
○ 2026-07-13 23:46:54

○NSns52.domaincontrol.com2017-04-01 → 2017-04-01 · 4 obs

○ 2016-04-10 18:17:10
● 2017-04-01 09:06:08
○ 2026-02-14 16:50:58
○ 2026-07-13 23:46:54

○NSns6.courserver.com2015-08-04 → 2016-04-10 · 4 obs

● 2015-08-04 12:44:04
● 2016-04-10 18:17:10
○ 2017-04-01 09:06:08
○ 2026-07-13 23:46:54

○MXmailstore1.europe.secureserver.net2015-08-04 → 2017-04-01 · 4 obs

● 2015-08-04 12:44:04
● 2017-04-01 09:06:08
○ 2026-02-14 16:50:58
○ 2026-07-13 23:46:54

●MXmx1.cloudhosting.net2026-06-11 → 2026-07-13 · 3 obs

○ 2026-05-27 07:39:50
● 2026-06-11 16:43:38
● 2026-07-13 23:46:54

●MXmx2.cloudhosting.net2026-06-11 → 2026-07-13 · 3 obs

○ 2026-05-27 07:39:50
● 2026-06-11 16:43:38
● 2026-07-13 23:46:54

○MXsmtp.courses.com2026-02-14 → 2026-05-27 · 5 obs

○ 2017-04-01 09:06:08
● 2026-02-14 16:50:58
● 2026-05-27 07:39:50
○ 2026-06-11 16:43:38
○ 2026-07-13 23:46:54

○MXsmtp.europe.secureserver.net2015-08-04 → 2017-04-01 · 4 obs

● 2015-08-04 12:44:04
● 2017-04-01 09:06:08
○ 2026-02-14 16:50:58
○ 2026-07-13 23:46:54

●A104.21.80.2502026-02-14 → 2026-07-13 · 3 obs

○ 2017-04-01 09:06:08
● 2026-02-14 16:50:58
● 2026-07-13 23:46:54

●A172.67.136.862026-02-14 → 2026-07-13 · 3 obs

○ 2017-04-01 09:06:08
● 2026-02-14 16:50:58
● 2026-07-13 23:46:54

○A2606:4700:3030::6815:50fa2026-02-14 → 2026-06-11 · 5 obs

○ 2017-04-01 09:06:08
● 2026-02-14 16:50:58
● 2026-06-11 16:43:38
○ 2026-07-01 15:41:28
○ 2026-07-13 23:46:54

●A2606:4700:3032::ac43:88562026-07-01 → 2026-07-13 · 3 obs

○ 2026-06-11 16:43:38
● 2026-07-01 15:41:28
● 2026-07-13 23:46:54

●A2606:4700:3033::6815:50fa2026-07-01 → 2026-07-13 · 3 obs

○ 2026-06-11 16:43:38
● 2026-07-01 15:41:28
● 2026-07-13 23:46:54

○A2606:4700:3033::ac43:88562026-02-14 → 2026-06-11 · 5 obs

○ 2017-04-01 09:06:08
● 2026-02-14 16:50:58
● 2026-06-11 16:43:38
○ 2026-07-01 15:41:28
○ 2026-07-13 23:46:54

○A64.131.82.1502015-08-04 → 2017-04-01 · 4 obs

● 2015-08-04 12:44:04
● 2017-04-01 09:06:08
○ 2026-02-14 16:50:58
○ 2026-07-13 23:46:54

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
com	h.gtld-servers.net, f.gtld-servers.net, g.gtld-servers.net, i.gtld-servers.net...	-
courses.com	clarissa.ns.cloudflare.com, colin.ns.cloudflare.com	12 records

✅ Authoritative Response

Server:108.162.194.123

NS records: clarissa.ns.cloudflare.com, colin.ns.cloudflare.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for courses.com (unsigned zone)

⏱️ Timing

Total: 214ms | Queries: -

📄 Records

Type	Count	Sample Data
A	2	`172.67.136.86, 104.21.80.250`
AAAA	2	`2606:4700:3032::ac43:8856, 2606:4700:3033::6815:50fa`
NS	2	`clarissa.ns.cloudflare.com, colin.ns.cloudflare.com`
MX	2	`mx1.cloudhosting.net (pri: 10), mx2.cloudhosting.net (pri: 20)`
TXT	1	`v=spf1 a:mail.courses.com include:spf.ah`
HTTPS	1	`{"priority":1,"target":".","alpn":["h3",`
SOA	1	`clarissa.ns.cloudflare.com dns.cloudflar`

📌 Glue Records Collected

Total: 12

Out-of-bailiwick: 12 (clarissa.ns.cloudflare.com, clarissa.ns.cloudflare.com, clarissa.ns.cloudflare.com...)

Analysis

Hierarchy

courses.com is a parent domain, with smtp.courses.com, 39428.courses.com and www.courses.com beneath it.

IP Addresses

courses.com has four IP addresses: 104.21.80.250, 172.67.136.86, 2606:4700:3032::ac43:8856 and 2606:4700:3033::6815:50fa.

Two other host names, along with suratonline.in, hostmaster.naturateraz.pl and mx50.harichu.net, also share IP numbers with courses.com.

Name Servers

DNS delegation for courses.com points to two name servers: clarissa.ns.cloudflare.com and colin.ns.cloudflare.com.

courses.com shares its NS records with other domains, for example biosk.in, maof.org, a0i.ir and two others.

courses.com has at least partial name server overlap with other domains, such as yqzzp.com, 077231.cfd, pyjs.com and two others.

It is common to find these name servers paired with the name servers amanda.ns.cloudflare.com, jay.ns.cloudflare.com, jarred.ns.cloudflare.com and jewel.ns.cloudflare.com.

DNS names with 6 IP addresses:

clarissa.ns.cloudflare.com has IP addresses 108.162.194.123, 162.159.38.123 and 172.64.34.123, plus 3 other.

colin.ns.cloudflare.com has IP addresses 108.162.195.75, 162.159.44.75 and 172.64.35.75, plus 3 other.

Mail Servers

courses.com is served by two mail servers, mx1.cloudhosting.net and mx2.cloudhosting.net.

Among the domains sharing a mail server setup with courses.com are websiteworking.info, stoveglass.co.uk, electricvehiclesolutions.net and two others.

mx1.cloudhosting.net directs to 185.53.56.44 and 185.53.56.46. mx2.cloudhosting.net directs to 185.53.56.45 and 185.53.56.47. Each host name carries two IP addresses.