course.com - dns.ninja

`course.com`

DNSSEC	⚠️ Not signed
A	69.32.208.74^{🇺🇸 RoadRunner69.32.208.0/22 Proxy-registered route object for Cengage Learning Inc Attn Communications in CSO Mason, OH 45040}
		PTR	`cengagebrain.ae`
		PTR	`adjuncts.biz`
		PTR	`bibliobase.biz`
		PTR	`eduspace.biz`
		PTR	`facultytraining.biz`
		PTR	`geologylink.biz`
		PTR	`cengagebrain.ca`
		PTR	`weinspirefutures.ca`
		PTR	`4letterpress.com`
		PTR	`adjuncts.com`
		PTR	`americaatodds.com`
		PTR	`appliedcalc.com`
		PTR	`atomicdog.com`
		PTR	`atomicdogpublishing.com`
		PTR	`bernielearning.com`
		PTR	`berniestypingtravels.com`
		PTR	`bibliobase.com`
		PTR	`busn4me.com`
		PTR	`c21accounting.com`
		PTR	`cengagebrainasia.com`
		PTR	`cengagebraindead.com`
		PTR	`cengagebraindrain.com`
		PTR	`cengagebrainless.com`
		PTR	`cengagebrane.com`
		PTR	`cengagecareers.com`
		PTR	`cengagecustom.com`
		PTR	`cengageextracredit.com`
		PTR	`cengageheinle.com`
		PTR	`cengagehookup.com`
		PTR	`cengagelearning.com`
		PTR	`cengagemind.com`
		PTR	`cengagemindtap.com`
		PTR	`centgage.com`
		PTR	`cerlabs.com`
		PTR	`cjinaction.com`
		PTR	`collegekeyboarding.com`
		PTR	`contemporarybusiness.com`
		PTR	`contemporarymath.com`
		PTR	`copperhouse.com`
		PTR	`corpfin4me.com`
		PTR	`corpview.com`
		PTR	`course.com`
		PTR	`courseclips.com`
		PTR	`coursecontinuinged.com`
		PTR	`coursedirect.com`
		PTR	`cyberstopmedia.com`
		PTR	`delmarfacultydevelopment.com`
		PTR	`ecram.com`
		PTR	`eduspacecodes.com`
		PTR	`eltcloseup.com`
		PTR	`eltexampreparation.com`
		PTR	`eltkeynote.com`
		PTR	`eltoutcomes.com`
		PTR	`eriginality.com`
		PTR	`etexere.com`
		PTR	`fepeacock.com`
		PTR	`fin4me.com`
		PTR	`finiteandcalc.com`
		PTR	`finitemath.com`
		PTR	`finitemathtutor.com`
		PTR	`fourletterlearning.com`
		PTR	`fourletterpress.com`
		PTR	`g3oceanography.com`
		PTR	`gale-la.com`
		PTR	`galecengage-publicdomain.com`
		PTR	`galelacengage.com`
		PTR	`galeresearcher.com`
		PTR	`getstudious.com`
		PTR	`greenhaven.com`
		PTR	`gwuser.com`
		PTR	`heinlecengage.com`
		PTR	`hybridtexts.com`
		PTR	`ib4m3.com`
		PTR	`ibus4me.com`
		PTR	`infosystems-online.com`
		PTR	`internationalcengage.com`
		PTR	`investigale.com`
		PTR	`investigatingyourcareer.com`
		PTR	`itbp.com`
		PTR	`jogd.com`
		PTR	`keepingtherepublic.com`
		PTR	`keyboarding.com`
		PTR	`kidhavenpress.com`
		PTR	`learn2key.com`
		PTR	`learnby.com`
		PTR	`learnbyseries.com`
		PTR	`learnflow.com`
		PTR	`learntokey.com`
		PTR	`lifecenter.com`
		PTR	`lucentbooks.com`
		PTR	`macro4me.com`
		PTR	`meguffey.com`
		PTR	`mgmt4me.com`
		PTR	`mgmtskills4me.com`
		PTR	`milady-la.com`
		PTR	`miladybeat.com`
		PTR	`mindapps.com`
		PTR	`mktg4me.com`
		PTR	`nationalgeographiclearning.com`
		PTR	`nelsonliteracy.com`
		PTR	`nelsonvhrm.com`
		PTR	`nglelt.com`
		PTR	`nglife.com`
		PTR	`orgb4me.com`
		PTR	`planningworks.com`
		PTR	`pop4e.com`
		PTR	`pse6.com`
		PTR	`pse7.com`
		PTR	`psmedia.com`
		PTR	`reminiscences.com`
		PTR	`riverwithin.com`
		PTR	`sallyseries.com`
		PTR	`schirmercengage.com`
		PTR	`school-to-careers.com`
		PTR	`scseries.com`
		PTR	`seeingsociology.com`
		PTR	`serwayphysics.com`
		PTR	`signature-labs.com`
		PTR	`signaturelabs.com`
		PTR	`smartmove4me.com`
		PTR	`socstark10.com`
		PTR	`socstark9.com`
		PTR	`south-westernlearning.com`
		PTR	`southwesterncengage.com`
		PTR	`southwesternlearning.com`
		PTR	`speakingabout.com`
		PTR	`supplychain-online.com`
		PTR	`swbusinessprojects.com`
		PTR	`swpco.com`
		PTR	`taxforteens.com`
		PTR	`textchoice.com`
		PTR	`thegreendestination.com`
		PTR	`thomsonedu.com`
		PTR	`thomsonelearning.com`
		PTR	`thomsonlearning.com`
		PTR	`tlemea.com`
		PTR	`trophe.com`
		PTR	`trueoutcomes.com`
		PTR	`ubi-sw.com`
		PTR	`universityce.com`
		PTR	`visualizingsociology.com`
		PTR	`wadsworthcengage.com`
		PTR	`econ4me.eu`
		PTR	`mgmt4me.eu`
		PTR	`cengagebrain.hk`
		PTR	`facultytraining.info`
		PTR	`geologylink.info`
		PTR	`kidhavenpress.info`
		PTR	`lucentbooks.info`
		PTR	`nglearning.info`
		PTR	`weinspirefutures.info`
		PTR	`cengagebrain.jp`
		PTR	`cengagebrain.kr`
		PTR	`cengagebrain.lk`
		PTR	`investigale.mx`
		PTR	`4letterpress.net`
		PTR	`brookscolecengage.net`
		PTR	`busn4me.net`
		PTR	`cengage.net`
		PTR	`cengageheinle.net`
		PTR	`corpfin4me.net`
		PTR	`customcengage.net`
		PTR	`etexere.net`
		PTR	`fin4me.net`
		PTR	`fourletterlearning.net`
		PTR	`fourletterpress.net`
		PTR	`galeresearcher.net`
		PTR	`gwuser.net`
		PTR	`heinlecengage.net`
		PTR	`ib4m3.net`
		PTR	`ibus4me.net`
		PTR	`internationalcengage.net`
		PTR	`macro4me.net`
		PTR	`mgmt4me.net`
		PTR	`mgmtskills4me.net`
		PTR	`nationalgeographiclearning.net`
		PTR	`nglearning.net`
		PTR	`orgb4me.net`
		PTR	`schirmercengage.net`
		PTR	`schoolcengage.net`
		PTR	`southwesterncengage.net`
		PTR	`texere.net`
		PTR	`trueoutcomes.net`
		PTR	`wadsworthcengage.net`
		PTR	`weinspirefutures.net`
		PTR	`4letterpress.org`
		PTR	`bcom4me.org`
		PTR	`brookscolecengage.org`
		PTR	`busn4me.org`
		PTR	`cengageheinle.org`
		PTR	`corpfin4me.org`
		PTR	`customcengage.org`
		PTR	`etexere.org`
		PTR	`fin4me.org`
		PTR	`fourletterlearning.org`
		PTR	`fourletterpress.org`
		PTR	`galeresearcher.org`
		PTR	`heinlecengage.org`
		PTR	`ib4m3.org`
		PTR	`ibus4me.org`
		PTR	`internationalcengage.org`
		PTR	`macro4me.org`
		PTR	`mgmt4me.org`
		PTR	`mgmtskills4me.org`
		PTR	`ngextremeexplorer.org`
		PTR	`ngpathfinder.org`
		PTR	`ngpioneer.org`
		PTR	`ngyoungexplorer.org`
		PTR	`orgb4me.org`
		PTR	`schirmercengage.org`
		PTR	`schoolcengage.org`
		PTR	`southwesterncengage.org`
		PTR	`texere.org`
		PTR	`wadsworthcengage.org`
		PTR	`weinspirefutures.org`
		PTR	`cengagebrain.ph`
		PTR	`cengagebrain.pk`
		PTR	`cengagebrain.ru`
		PTR	`heinle-elt.ru`
		PTR	`heinle.ru`
		PTR	`cengagebrain.sg`
		PTR	`cengagebrain.tw`
		PTR	`greenhaven.us`
		PTR	`kidhavenpress.us`
		PTR	`cengage.com.ar`
		PTR	`cengagelearning.com.ar`
		PTR	`cengagebrain.com.bd`
		PTR	`cengage.com.br`
		PTR	`cengagebrain.com.br`
		PTR	`cengagelearning.com.br`
		PTR	`thomsonlearning.com.br`
		PTR	`cengage.com.co`
		PTR	`course.cengage.com`
		PTR	`coursedirect.cengage.com`
		PTR	`icpnacpt.cengage.com`
		PTR	`origin-college.cengage.com`
		PTR	`www2-i.cengage.com`
		PTR	`www2.cengage.com`
		PTR	`oc.course.com`
		PTR	`sam2007sm.course.com`
		PTR	`sam2010psm.course.com`
		PTR	`sam2010sm.course.com`
		PTR	`www.course.com`
		PTR	`pdf.educationdirect.com`
		PTR	`www.eltkeynote.com`
		PTR	`www.learnby.com`
		PTR	`cengagebrain.com.eu`
		PTR	`cengagebrain.com.hk`
		PTR	`cengagebrain.co.id`
		PTR	`cengagebrain.co.il`
		PTR	`cengagebrain.co.in`
		PTR	`cengagebrain.co.kr`
		PTR	`cengagebrain.com.lk`
		PTR	`cengagelearning.com.mx`
		PTR	`investigale.com.mx`
		PTR	`cengagebrain.com.my`
		PTR	`cengagebrain.com.ph`
		PTR	`cengagebrain.com.pk`
		PTR	`cengagebrain.com.sg`
		PTR	`cengagebrain.com.tw`
		PTR	`cengageheinle.co.uk`
		PTR	`eltexampreparation.co.uk`
		PTR	`eltkeynote.co.uk`
		PTR	`eltoutcomes.co.uk`
		PTR	`mcelt.co.uk`
		PTR	`nationalgeographiclife.co.uk`
		PTR	`psych.co.uk`
		PTR	`summertown.co.uk`
		PTR	`cengagebrain.com.vn`
		PTR	`www.support.gale.com`
NS	`ns1x.cengage.net` ⭐ ⚠️ Not in parent delegation
		A	69.32.130.251^{🇺🇸 RoadRunner69.32.130.0/23 Proxy-registered route object for Cengage Learning Inc Attn Communications in CSO Mason, OH 45040}
			PTR	`ns1x.cengage.net`
NS	`dns1.p01.nsone.net` ⚠️ Not in zone NS records
		A	2620:4d:4000:6259:7:1:0:1^{🇺🇸 NSONE2620:4d:4000::/48 2620:4D:4000::/48}
			PTR	`dns1.p01.nsone.net`
		A	198.51.44.1^{🇺🇸 NSONE198.51.44.0/24 198.51.44.0}
			PTR	`dns1.p01.nsone.net`
NS	`dns2.p01.nsone.net` ⚠️ Not in zone NS records
		A	2a00:edc0:6259:7:1::2^{🇺🇸 NSONE2a00:edc0:6259::/48 NS1-2}
			PTR	`dns2.p01.nsone.net`
		A	198.51.45.1^{🇺🇸 NSONE198.51.45.0/24 198.51.45.0}
			PTR	`dns2.p01.nsone.net`
NS	`dns3.p01.nsone.net` ⚠️ Not in zone NS records
		A	2620:4d:4000:6259:7:1:0:3^{🇺🇸 NSONE2620:4d:4000::/48 2620:4D:4000::/48}
			PTR	`dns3.p01.nsone.net`
		A	198.51.44.65^{🇺🇸 NSONE198.51.44.0/24 198.51.44.0}
			PTR	`dns3.p01.nsone.net`
NS	`dns4.p01.nsone.net` ⚠️ Not in zone NS records
		A	2a00:edc0:6259:7:1::4^{🇺🇸 NSONE2a00:edc0:6259::/48 NS1-2}
			PTR	`dns4.p01.nsone.net`
		A	198.51.45.65^{🇺🇸 NSONE198.51.45.0/24 198.51.45.0}
			PTR	`dns4.p01.nsone.net`
NS	`ns2x.cengage.net` ⚠️ Not in parent delegation
		A	69.32.224.38^{🇺🇸 RoadRunner69.32.224.0/24 Proxy-registered route object for Cengage Learning Inc Attn Communications in CSO Mason, OH 45040}
			PTR	`kyindxns4.cengage.net`
			PTR	`ns2.cengage.net`
MX	`mxa-0012df01.gslb.pphosted.com` ⭐
		A	148.163.146.140^{🇺🇸 Proofpoint148.163.146.0/24 Inc.}
			PTR	`mx0a-0012df01.pphosted.com`
MX	`mxb-0012df01.gslb.pphosted.com` ⭐
		A	148.163.146.140^{🇺🇸 Proofpoint148.163.146.0/24 Inc.}
			PTR	`mx0a-0012df01.pphosted.com`
TXT	`MS=ms17115631`
TXT	`v=spf1 include:spf.cengage.com -all`
SOA	`ns1x.cengage.net`hostmaster@ohcinmason.com serial=392

`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=1782378735

rank #578578 globally
rank #251928 in the tld
WOT: SAFE (94/100)

PTR for

74.208.32.69.in-addr.arpa

Subdomains

new.course.com

www.course.com

ftp.course.com

sam2007sm.course.com

sam2010psm.course.com

sam2010sm.course.com

mm.course.com

oc.course.com

owl.course.com

practicetest.course.com

chubb.course.com

Same first word

course.biz

course.school

course.eu

course.tv

course.academy

course.camp

course.guru

course.be

course.ltd

course.net

course.care

course.com.tr

course.istanbul

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course.run

course.nl

course.ws

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course.tours

course.pl

course.io

course.studio

course.im

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course.design

course.place

course.city

course.by

course.com

course.network

course.guide

course.org.il

course.media

course.mobi

course.edu.vn

course.company

course.xyz

course.co

course.market

course.cafe

course.london

course.tc

course.la

course.it

course.am

course.info

course.institute

course.id

course.com.cn

course.coach

course.pub

course.careers

course.chat

course.ru

course.online

course.co.uk

course.cc

course.fr

course.us

course.pro

course.co.za

course.org

course.world

course.dk

course.center

course.rs

course.work

course.link

course.ist

course.ca

course.is

Similar names

ruesco.com

securo.in

source.gr

scoure.de

securo.org

securo.de

crouse.name

serocu.police.uk

oursec.com

source.mobi

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crouse.com

socure.biz

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securo.it

crusoe.ai

ecorus.dk

source.co

source.com.tr

crusoe.cloud

source.plus

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eurocs.it

corsue.com

source.com.pl

uscore.com

source.coop

source.graphics

source.aero

ecosur.com

eurocs.ru

eurocs.co.uk

soucer.com.br

uscore.net

source.mn

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crouse.ir

source.tube

ecosur.edu.mx

coreus.net

ecosur.fr

oscure.com

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coeurs.com

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source.ba

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source.works

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crusoe.ch

coreus.co

source.ru

ecorus.com

osecur.be

source.care

source.synology.me

escuro.com.br

ruseco.ru

ruscoe.com

source.at

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secuor.ca

source.run

source.ws

crouse.us

crusoe.wiki

sureco.pl

curose.com

source.info

ecorus.net

ocreus.co.uk

secour.de

escuro.net.br

DNS History

26 records (9 active, 17 former)

○NSa1-49.akam.net2026-02-15 → 2026-05-03 · 5 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-05-03 04:21:46
○ 2026-05-06 08:14:56
○ 2026-06-25 09:39:24

○NSa13-64.akam.net2026-02-15 → 2026-05-03 · 5 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-05-03 04:21:46
○ 2026-05-06 08:14:56
○ 2026-06-25 09:39:24

○NSa14-65.akam.net2026-02-15 → 2026-05-03 · 5 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-05-03 04:21:46
○ 2026-05-06 08:14:56
○ 2026-06-25 09:39:24

●NSdns1.p01.nsone.net2026-02-15 → 2026-06-25 · 3 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-06-25 09:39:24

●NSdns2.p01.nsone.net2026-02-15 → 2026-06-25 · 3 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-06-25 09:39:24

○NSdns3.gale.com2009-07-02 → 2009-07-02 · 3 obs

● 2009-07-02 09:41:32
○ 2015-09-03 04:14:10
○ 2026-06-25 09:39:24

●NSdns3.p01.nsone.net2026-02-15 → 2026-06-25 · 3 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-06-25 09:39:24

○NSdns4.gale.com2009-07-02 → 2009-07-02 · 3 obs

● 2009-07-02 09:41:32
○ 2015-09-03 04:14:10
○ 2026-06-25 09:39:24

●NSdns4.p01.nsone.net2026-05-06 → 2026-06-25 · 3 obs

○ 2026-05-03 04:21:46
● 2026-05-06 08:14:56
● 2026-06-25 09:39:24

○NSns1.cengage.net2015-09-03 → 2017-09-20 · 5 obs

○ 2009-07-02 09:41:32
● 2015-09-03 04:14:10
● 2017-09-20 11:01:14
○ 2026-02-15 09:12:32
○ 2026-06-25 09:39:24

●NSns1x.cengage.net2026-02-15 → 2026-06-25 · 3 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-06-25 09:39:24

○NSns2.cengage.net2015-09-03 → 2017-09-20 · 5 obs

○ 2009-07-02 09:41:32
● 2015-09-03 04:14:10
● 2017-09-20 11:01:14
○ 2026-02-15 09:12:32
○ 2026-06-25 09:39:24

●NSns2x.cengage.net2026-02-15 → 2026-06-25 · 3 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-06-25 09:39:24

○NSns3.ohcinmason.com2009-07-02 → 2009-07-02 · 3 obs

● 2009-07-02 09:41:32
○ 2015-09-03 04:14:10
○ 2026-06-25 09:39:24

○NSns4.ohcinmason.com2009-07-02 → 2009-07-02 · 3 obs

● 2009-07-02 09:41:32
○ 2015-09-03 04:14:10
○ 2026-06-25 09:39:24

○NSns5.ohcinmason.com2009-07-02 → 2009-07-02 · 3 obs

● 2009-07-02 09:41:32
○ 2015-09-03 04:14:10
○ 2026-06-25 09:39:24

○MXkyindmx01.cengagelearning.com2015-09-03 → 2017-09-20 · 5 obs

○ 2009-07-02 09:41:32
● 2015-09-03 04:14:10
● 2017-09-20 11:01:14
○ 2026-02-15 09:12:32
○ 2026-06-25 09:39:24

○MXkyindmx02.cengagelearning.com2015-09-03 → 2017-09-20 · 5 obs

○ 2009-07-02 09:41:32
● 2015-09-03 04:14:10
● 2017-09-20 11:01:14
○ 2026-02-15 09:12:32
○ 2026-06-25 09:39:24

●MXmxa-0012df01.gslb.pphosted.com2026-02-15 → 2026-06-25 · 3 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-06-25 09:39:24

●MXmxb-0012df01.gslb.pphosted.com2026-02-15 → 2026-06-25 · 3 obs

○ 2017-09-20 11:01:14
● 2026-02-15 09:12:32
● 2026-06-25 09:39:24

○MXohcinmx01.cengagelearning.com2015-09-03 → 2017-09-20 · 5 obs

○ 2009-07-02 09:41:32
● 2015-09-03 04:14:10
● 2017-09-20 11:01:14
○ 2026-02-15 09:12:32
○ 2026-06-25 09:39:24

○MXohcinmx02.cengagelearning.com2015-09-03 → 2017-09-20 · 5 obs

○ 2009-07-02 09:41:32
● 2015-09-03 04:14:10
● 2017-09-20 11:01:14
○ 2026-02-15 09:12:32
○ 2026-06-25 09:39:24

○MXsmtp-in1.thomsonlearning.com2009-07-02 → 2009-07-02 · 3 obs

● 2009-07-02 09:41:32
○ 2015-09-03 04:14:10
○ 2026-06-25 09:39:24

○A69.32.142.1092009-07-02 → 2009-07-02 · 3 obs

● 2009-07-02 09:41:32
○ 2015-09-03 04:14:10
○ 2026-06-25 09:39:24

○A69.32.148.1242015-09-03 → 2016-06-18 · 5 obs

○ 2009-07-02 09:41:32
● 2015-09-03 04:14:10
● 2016-06-18 00:50:20
○ 2016-06-27 10:46:02
○ 2026-06-25 09:39:24

●A69.32.208.742016-06-27 → 2026-06-25 · 3 obs

○ 2016-06-18 00:50:20
● 2016-06-27 10:46:02
● 2026-06-25 09:39:24

🔍 DNS Trace

📋 Delegation Chain

Zone	Nameservers	Glue
com	b.gtld-servers.net, l.gtld-servers.net, i.gtld-servers.net, a.gtld-servers.net...	-
course.com	dns1.p01.nsone.net, dns2.p01.nsone.net, dns3.p01.nsone.net, dns4.p01.nsone.net	-

✅ Authoritative Response

Server:198.51.45.65

NS records: dns1.p01.nsone.net, dns2.p01.nsone.net, dns3.p01.nsone.net, dns4.p01.nsone.net

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for course.com (unsigned zone)

⏱️ Timing

Total: 672ms | Queries: -

📄 Records

Type	Count	Sample Data
A	1	`69.32.208.74`
NS	2	`ns1x.cengage.net, ns2x.cengage.net`
MX	2	`mxa-0012df01.gslb.pphosted.com (pri: 10), mxb-0012df01.gslb.pphosted.com (pri: 10)`
TXT	2	`MS=ms17115631, v=spf1 include:spf.cengage.com -all`
SOA	1	`ns1x.cengage.net hostmaster.ohcinmason.c`

Analysis

Hierarchy

course.com is the parent domain of new.course.com, www.course.com, ftp.course.com, sam2007sm.course.com, sam2010psm.course.com and a few other host names.

IP Addresses

course.com directs to one IP number, which is 69.32.208.74.

Among the host names that share IP numbers with course.com are finitemathtutor.com, cengagelearning.eu, cengagebrain.kr and two others.

Name Servers

course.com is served by 6 authoritative name servers — among them ns1x.cengage.net, ns2x.cengage.net, dns1.p01.nsone.net and 3 others.

course.com shares at least some of its name servers with other domains, including therapglobal.net, criptohome.app, sedanser.com and two others.

These name servers are frequently seen alongside dns2.p01.nsone.net, dns3.p01.nsone.net, dns4.p01.nsone.net and 7 other name servers.

Hosts with two IP numbers each:

dns1.p01.nsone.net resolves to two addresses: 198.51.44.1 and 2620:4d:4000:6259:7:1:0:1.

dns2.p01.nsone.net resolves to two addresses: 198.51.45.1 and 2a00:edc0:6259:7:1::2.

dns3.p01.nsone.net resolves to two addresses: 198.51.44.65 and 2620:4d:4000:6259:7:1:0:3.

dns4.p01.nsone.net resolves to two addresses: 198.51.45.65 and 2a00:edc0:6259:7:1::4.

Hosts that resolve to one IP address:

The hostname ns1x.cengage.net resolves to 69.32.130.251.

The hostname ns2x.cengage.net resolves to 69.32.224.38.

Mail Servers

The MX records for course.com point to two mail servers: mxa-0012df01.gslb.pphosted.com and mxb-0012df01.gslb.pphosted.com.

course.com has the same mail server arrangement as a number of other domains, for example miladypro.com, ed2go.com, ilrn-support.com and two more.

mxa-0012df01.gslb.pphosted.com directs to 148.163.146.140, as does mxb-0012df01.gslb.pphosted.com — both hostnames resolve to that one IP address.

mxa-0012df01.gslb.pphosted.com along with mxb-0012df01.gslb.pphosted.com each resolve to 148.163.146.140 IP addresses.