courseoff.com - robtex.com

courseoff.com

DNSSEC⚠️ Not signed
A2607:f8b0:4004:c08::79🇺🇸 Google2607:f8b0:4004::/48
PTRbi-in-f121.1e100.net
A142.251.179.121🇺🇸 Google142.251.179.0/24
NSjill.ns.cloudflare.com ⭐
A2606:4700:50::adf5:3a7a🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjill.ns.cloudflare.com
A2803:f800:50::6ca2:c07a🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L
PTRjill.ns.cloudflare.com
A2a06:98c1:50::ac40:207a🇺🇸 Cloudflare2a06:98c1:50::/45
PTRjill.ns.cloudflare.com
A108.162.192.122🇺🇸 Cloudflare108.162.192.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjill.ns.cloudflare.com
A172.64.32.122🇺🇸 Cloudflare172.64.32.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjill.ns.cloudflare.com
A173.245.58.122🇺🇸 Cloudflare173.245.58.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRjill.ns.cloudflare.com
NSnorm.ns.cloudflare.com
A2606:4700:58::adf5:3b86🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRnorm.ns.cloudflare.com
A2803:f800:50::6ca2:c186🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L
PTRnorm.ns.cloudflare.com
A2a06:98c1:50::ac40:2186🇺🇸 Cloudflare2a06:98c1:50::/45
PTRnorm.ns.cloudflare.com
A108.162.193.134🇺🇸 Cloudflare108.162.193.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRnorm.ns.cloudflare.com
A172.64.33.134🇺🇸 Cloudflare172.64.33.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRnorm.ns.cloudflare.com
A173.245.59.134🇺🇸 Cloudflare173.245.59.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US
PTRnorm.ns.cloudflare.com
MXaspmx.l.google.com ⭐
A2607:f8b0:4004:c19::1b🇺🇸 Google2607:f8b0:4004::/48
PTRbk-in-f27.1e100.net
A172.253.62.27🇺🇸 Google172.253.62.0/24
PTRbc-in-f27.1e100.net
MXalt1.aspmx.l.google.com(5)
A2607:f8b0:4003:c30::1b🇺🇸 Google2607:f8b0:4003::/48
PTRyutulis-in-f27.1e100.net
A74.125.27.26🇺🇸 Google74.125.27.0/24
PTRyutulis-in-f26.1e100.net
MXalt2.aspmx.l.google.com(5)
A2607:f8b0:4001:c70::1a🇺🇸 Google2607:f8b0:4001::/48
PTRyucbful-in-f26.1e100.net
A192.178.209.26🇺🇸 Google192.178.209.0/24
PTRyucbful-in-f26.1e100.net
MXaspmx2.googlemail.com(10)
A2607:f8b0:4003:c30::1b🇺🇸 Google2607:f8b0:4003::/48
PTRyutulis-in-f27.1e100.net
A74.125.27.27🇺🇸 Google74.125.27.0/24
PTRyutulis-in-f27.1e100.net
MXaspmx3.googlemail.com(10)
A2607:f8b0:4001:c70::1a🇺🇸 Google2607:f8b0:4001::/48
PTRyucbful-in-f26.1e100.net
A192.178.209.27🇺🇸 Google192.178.209.0/24
PTRyucbful-in-f27.1e100.net
TXTgoogle-site-verification=zYsua1eZWJrdP8LGtVJLIxO52VLTPSTz2PhRGZaZwXs
TXTv=spf1 include:spf.mailjet.com ~all
SOAjill.ns.cloudflare.comdns@cloudflare.com serial=2396638782

com

DNSSEC🔒 Signed (DS record present)
NSa.gtld-servers.net ⭐
NSb.gtld-servers.net
NSc.gtld-servers.net
NSd.gtld-servers.net
NSe.gtld-servers.net
NSf.gtld-servers.net
NSg.gtld-servers.net
NSh.gtld-servers.net
NSi.gtld-servers.net
NSj.gtld-servers.net
NSk.gtld-servers.net
NSl.gtld-servers.net
NSm.gtld-servers.net
SOAa.gtld-servers.netnstld@verisign-grs.com serial=1771291435

Subdomains

emory.courseoff.com
gatech.courseoff.com
soc.courseoff.com

Same first word

courseoff.com

Similar names

offcourse.co
offcourse.nl
offcourse.org
offcourse.golf
offcourse.com.tr
freofocus.com.au
forefocus.com
offcourse.io
offcourse.dk
offcourse.bike
offcourse.se
offcourse.no
offcourse.biz
offcourse.be
offcourse.com
offcourse.ca
offcourse.de
offsource.com
offcourse.in

DNS History

43 records (9 active, 34 former)

20162017201820192020202120222023202420252026NSjill.ns.cloudflare.comnorm.ns.cloudflare.comns1.digitalocean.comns2.digitalocean.comns3.digitalocean.comMXalt1.aspmx.l.google.comalt2.aspmx.l.google.comaspmx.l.google.comaspmx2.googlemail.comaspmx3.googlemail.comA142.251.179.1212607:f8b0:4004:c08::79104.131.107.166104.131.39.13104.28.28.53104.28.29.53104.31.248.79104.31.249.79142.250.72.147142.251.16.121142.251.167.121142.251.210.147142.251.32.179142.251.45.19159.203.148.203172.253.63.121192.178.155.121192.178.218.121216.58.208.1152400:cb00:2048:1::681f:f84f2400:cb00:2048:1::681f:f94f2606:4700:3031::681c:1d352606:4700:3036::681c:1c352607:f8b0:4004:c07::792607:f8b0:4004:c19::792607:f8b0:4004:c1b::792607:f8b0:4004:c1f::792607:f8b0:4004:c21::792607:f8b0:4007:804::20132607:f8b0:4007:806::20132607:f8b0:4007:808::20132a00:1450:400e:807::201345.55.126.58
●NSjill.ns.cloudflare.com2017-02-13 → 2026-03-14 · 3 obs
○ 2016-07-09 08:35:02
● 2017-02-13 16:24:54
● 2026-03-14 06:52:28
●NSnorm.ns.cloudflare.com2017-02-13 → 2026-03-14 · 3 obs
○ 2016-07-09 08:35:02
● 2017-02-13 16:24:54
● 2026-03-14 06:52:28
○NSns1.digitalocean.com2015-07-16 → 2016-07-09 · 4 obs
● 2015-07-16 22:00:12
● 2016-07-09 08:35:02
○ 2017-02-13 16:24:54
○ 2026-03-14 06:52:28
○NSns2.digitalocean.com2015-07-16 → 2016-07-09 · 4 obs
● 2015-07-16 22:00:12
● 2016-07-09 08:35:02
○ 2017-02-13 16:24:54
○ 2026-03-14 06:52:28
○NSns3.digitalocean.com2015-07-16 → 2016-07-09 · 4 obs
● 2015-07-16 22:00:12
● 2016-07-09 08:35:02
○ 2017-02-13 16:24:54
○ 2026-03-14 06:52:28
●MXalt1.aspmx.l.google.com2015-07-16 → 2026-03-14 · 2 obs
● 2015-07-16 22:00:12
● 2026-03-14 06:52:28
●MXalt2.aspmx.l.google.com2015-07-16 → 2026-03-14 · 2 obs
● 2015-07-16 22:00:12
● 2026-03-14 06:52:28
●MXaspmx.l.google.com2015-07-16 → 2026-03-14 · 2 obs
● 2015-07-16 22:00:12
● 2026-03-14 06:52:28
●MXaspmx2.googlemail.com2015-07-16 → 2026-03-14 · 2 obs
● 2015-07-16 22:00:12
● 2026-03-14 06:52:28
●MXaspmx3.googlemail.com2015-07-16 → 2026-03-14 · 2 obs
● 2015-07-16 22:00:12
● 2026-03-14 06:52:28
○A104.131.107.1662015-07-16 → 2015-07-16 · 3 obs
● 2015-07-16 22:00:12
○ 2015-10-01 09:44:32
○ 2026-03-14 06:52:28
○A104.131.39.132015-10-01 → 2016-01-07 · 5 obs
○ 2015-07-16 22:00:12
● 2015-10-01 09:44:32
● 2016-01-07 22:10:28
○ 2016-02-09 09:09:08
○ 2026-03-14 06:52:28
○A104.28.28.532020-03-02 → 2020-03-02 · 4 obs
○ 2017-02-13 16:24:54
● 2020-03-02 23:30:46
○ 2026-02-22 08:43:10
○ 2026-03-14 06:52:28
○A104.28.29.532020-03-02 → 2020-03-02 · 4 obs
○ 2017-02-13 16:24:54
● 2020-03-02 23:30:46
○ 2026-02-22 08:43:10
○ 2026-03-14 06:52:28
○A104.31.248.792017-02-13 → 2017-02-13 · 4 obs
○ 2016-07-09 08:35:02
● 2017-02-13 16:24:54
○ 2020-03-02 23:30:46
○ 2026-03-14 06:52:28
○A104.31.249.792017-02-13 → 2017-02-13 · 4 obs
○ 2016-07-09 08:35:02
● 2017-02-13 16:24:54
○ 2020-03-02 23:30:46
○ 2026-03-14 06:52:28
○A142.250.72.1472026-02-22 → 2026-02-22 · 4 obs
○ 2020-03-02 23:30:46
● 2026-02-22 08:43:10
○ 2026-02-26 18:15:02
○ 2026-03-14 06:52:28
○A142.251.16.1212026-02-27 → 2026-02-27 · 4 obs
○ 2026-02-26 18:15:02
● 2026-02-27 14:45:34
○ 2026-02-28 17:42:08
○ 2026-03-14 06:52:28
○A142.251.167.1212026-03-08 → 2026-03-12 · 7 obs
○ 2026-03-08 17:28:24
● 2026-03-08 18:54:50
○ 2026-03-08 22:41:48
○ 2026-03-10 19:12:22
● 2026-03-12 05:15:06
○ 2026-03-14 06:52:26
○ 2026-03-14 06:52:28
●A142.251.179.1212026-03-14 → 2026-03-14 · 3 obs
○ 2026-03-12 05:15:06
● 2026-03-14 06:52:26
● 2026-03-14 06:52:28
○A142.251.210.1472026-02-28 → 2026-02-28 · 4 obs
○ 2026-02-28 17:42:08
● 2026-02-28 20:13:44
○ 2026-03-02 23:55:02
○ 2026-03-14 06:52:28
○A142.251.32.1792026-02-26 → 2026-02-26 · 4 obs
○ 2026-02-22 08:43:10
● 2026-02-26 18:15:02
○ 2026-02-27 14:45:34
○ 2026-03-14 06:52:28
○A142.251.45.192026-03-02 → 2026-03-02 · 4 obs
○ 2026-02-28 20:13:44
● 2026-03-02 23:55:02
○ 2026-03-05 04:53:18
○ 2026-03-14 06:52:28
○A159.203.148.2032016-02-09 → 2016-02-09 · 4 obs
○ 2016-01-07 22:10:28
● 2016-02-09 09:09:08
○ 2016-07-09 08:35:02
○ 2026-03-14 06:52:28
○A172.253.63.1212026-03-08 → 2026-03-10 · 7 obs
○ 2026-03-05 04:53:18
● 2026-03-08 17:28:24
○ 2026-03-08 18:54:50
○ 2026-03-08 22:41:48
● 2026-03-10 19:12:22
○ 2026-03-12 05:15:06
○ 2026-03-14 06:52:28
○A192.178.155.1212026-03-05 → 2026-03-05 · 4 obs
○ 2026-03-02 23:55:02
● 2026-03-05 04:53:18
○ 2026-03-08 17:28:24
○ 2026-03-14 06:52:28
○A192.178.218.1212026-02-28 → 2026-02-28 · 5 obs
○ 2026-02-22 08:43:10
○ 2026-02-27 14:45:34
● 2026-02-28 17:42:08
○ 2026-02-28 20:13:44
○ 2026-03-14 06:52:28
○A216.58.208.1152026-03-08 → 2026-03-08 · 4 obs
○ 2026-03-08 18:54:50
● 2026-03-08 22:41:48
○ 2026-03-10 19:12:22
○ 2026-03-14 06:52:28
○A2400:cb00:2048:1::681f:f84f2017-02-13 → 2017-02-13 · 4 obs
○ 2016-07-09 08:35:02
● 2017-02-13 16:24:54
○ 2020-03-02 23:30:46
○ 2026-03-14 06:52:28
○A2400:cb00:2048:1::681f:f94f2017-02-13 → 2017-02-13 · 4 obs
○ 2016-07-09 08:35:02
● 2017-02-13 16:24:54
○ 2020-03-02 23:30:46
○ 2026-03-14 06:52:28
○A2606:4700:3031::681c:1d352020-03-02 → 2020-03-02 · 4 obs
○ 2017-02-13 16:24:54
● 2020-03-02 23:30:46
○ 2026-02-22 08:43:10
○ 2026-03-14 06:52:28
○A2606:4700:3036::681c:1c352020-03-02 → 2020-03-02 · 4 obs
○ 2017-02-13 16:24:54
● 2020-03-02 23:30:46
○ 2026-02-22 08:43:10
○ 2026-03-14 06:52:28
○A2607:f8b0:4004:c07::792026-03-12 → 2026-03-12 · 4 obs
○ 2026-03-10 19:12:22
● 2026-03-12 05:15:06
○ 2026-03-14 06:52:26
○ 2026-03-14 06:52:28
●A2607:f8b0:4004:c08::792026-03-08 → 2026-03-14 · 6 obs
○ 2026-03-05 04:53:18
● 2026-03-08 17:28:24
○ 2026-03-08 18:54:50
○ 2026-03-12 05:15:06
● 2026-03-14 06:52:26
● 2026-03-14 06:52:28
○A2607:f8b0:4004:c19::792026-02-28 → 2026-02-28 · 5 obs
○ 2026-02-22 08:43:10
○ 2026-02-27 14:45:34
● 2026-02-28 17:42:08
○ 2026-02-28 20:13:44
○ 2026-03-14 06:52:28
○A2607:f8b0:4004:c1b::792026-03-08 → 2026-03-08 · 4 obs
○ 2026-03-08 17:28:24
● 2026-03-08 18:54:50
○ 2026-03-08 22:41:48
○ 2026-03-14 06:52:28
○A2607:f8b0:4004:c1f::792026-02-27 → 2026-03-10 · 7 obs
○ 2026-02-26 18:15:02
● 2026-02-27 14:45:34
○ 2026-02-28 17:42:08
○ 2026-03-08 22:41:48
● 2026-03-10 19:12:22
○ 2026-03-12 05:15:06
○ 2026-03-14 06:52:28
○A2607:f8b0:4004:c21::792026-03-05 → 2026-03-05 · 4 obs
○ 2026-03-02 23:55:02
● 2026-03-05 04:53:18
○ 2026-03-08 17:28:24
○ 2026-03-14 06:52:28
○A2607:f8b0:4007:804::20132026-03-02 → 2026-03-02 · 4 obs
○ 2026-02-28 20:13:44
● 2026-03-02 23:55:02
○ 2026-03-05 04:53:18
○ 2026-03-14 06:52:28
○A2607:f8b0:4007:806::20132026-02-22 → 2026-02-28 · 7 obs
○ 2020-03-02 23:30:46
● 2026-02-22 08:43:10
○ 2026-02-26 18:15:02
○ 2026-02-28 17:42:08
● 2026-02-28 20:13:44
○ 2026-03-02 23:55:02
○ 2026-03-14 06:52:28
○A2607:f8b0:4007:808::20132026-02-26 → 2026-02-26 · 4 obs
○ 2026-02-22 08:43:10
● 2026-02-26 18:15:02
○ 2026-02-27 14:45:34
○ 2026-03-14 06:52:28
○A2a00:1450:400e:807::20132026-03-08 → 2026-03-08 · 4 obs
○ 2026-03-08 18:54:50
● 2026-03-08 22:41:48
○ 2026-03-10 19:12:22
○ 2026-03-14 06:52:28
○A45.55.126.582016-07-09 → 2016-07-09 · 4 obs
○ 2016-02-09 09:09:08
● 2016-07-09 08:35:02
○ 2017-02-13 16:24:54
○ 2026-03-14 06:52:28

🔍 DNS Trace

📋 Delegation Chain

ZoneNameserversGlue
coma.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net...-
courseoff.comjill.ns.cloudflare.com, norm.ns.cloudflare.com12 records

✅ Authoritative Response

Server: 108.162.193.134

NS records: jill.ns.cloudflare.com, norm.ns.cloudflare.com

🔒 DNSSEC Status

⚠️ Insecure (no DNSSEC)

No DS record for courseoff.com (unsigned zone)

⏱️ Timing

Total: 431ms | Queries: -

📄 Records

TypeCountSample Data
A1192.178.218.121
AAAA12607:f8b0:4004:c17::79
NS2jill.ns.cloudflare.com, norm.ns.cloudflare.com
MX5aspmx.l.google.com (pri: 1), aspmx2.googlemail.com (pri: 10)...
TXT2google-site-verification=zYsua1eZWJrdP8L, v=spf1 include:spf.mailjet.com ~all
SOA1jill.ns.cloudflare.com dns.cloudflare.co

📌 Glue Records Collected

Total: 12

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

Analysis

Hierarchy

courseoff.com has emory.courseoff.com, gatech.courseoff.com and soc.courseoff.com as children.

IP Addresses

courseoff.com points to two IP numbers: 2607:f8b0:4004:c08::79 and 142.251.179.121.

Other host names such as pub-2410912496431480.afd.ghs.google.com, pub-6567637956813164.afd.ghs.google.com, zaczavosgmail.feedproxy.ghs.google.com, pub-1016210274699772.afd.ghs.google.com and 21cwb8.feedproxy.ghs.google.com share IPs with courseoff.com.

Name Servers

Two name servers jill.ns.cloudflare.com and norm.ns.cloudflare.com handle the delegation for courseoff.com.

courseoff.com shares the same name server setup as other domains, for example tropicloud.net, poljoprom.ba, waterpolo.ru, bs.be and digitry.us.

courseoff.com at least partially shares name servers with other domains, for example khmersupermarket.com, capoeira4all.com, glassdoor.at, getacommerce.com and komarsendok.xyz.

These name servers are often used together with lady.ns.cloudflare.com and roman.ns.cloudflare.com.

Host names with six IP numbers:

jill.ns.cloudflare.com points to 2606:4700:50::adf5:3a7a, 2803:f800:50::6ca2:c07a, 2a06:98c1:50::ac40:207a, 108.162.192.122, 172.64.32.122 and 173.245.58.122.

norm.ns.cloudflare.com points to 2606:4700:58::adf5:3b86, 2803:f800:50::6ca2:c186, 2a06:98c1:50::ac40:2186, 108.162.193.134, 172.64.33.134 and 173.245.59.134.

Mail Servers

courseoff.com is handled by five mail servers: aspmx2.googlemail.com, aspmx3.googlemail.com, aspmx.l.google.com, alt1.aspmx.l.google.com and alt2.aspmx.l.google.com.

courseoff.com shares at least partially some mail servers with other domains, for instance ns500742.ns500754.ns500742.ns500731.ns500742.ns500731.ns500704.ns500731.ns500742.ns500688.ns500704.ns500671.ns500649.ns500649.ns500649.ns500153.tenderladiesbz.com, ns500759.ns500758.ns500759.ns500758.ns500735.ns500698.ns500736.ns500735.ns500698.ns500576.ns500576.ns500576.ns500652.ns500619.ns500576.trackreceptor.com, ns500731.ns500754.ns500731.ns500671.ns500704.ns500742.ns500742.ns500671.ns500678.ns500678.ns500678.ns500291.ns500291.ns500291.ns500291.ns500131.lustychickser.com, ns500768.ns500698.ns500698.ns500698.ns500735.ns500698.ns500735.ns500735.ns500708.ns500576.ns500619.ns500576.ns500619.trackreceptor.com and ns500699.ns500699.ns500693.ns500734.ns500734.ns500699.ns500683.ns500683.ns500588.ns500612.ns500612.ns500110.dtrkdll.com.

these mail servers are often used together with alt3.aspmx.l.google.com, alt4.aspmx.l.google.com, aspmx4.googlemail.com and aspmx5.googlemail.com.

Host names with two IPs

The host name aspmx2.googlemail.com points to 2607:f8b0:4003:c30::1b and 74.125.27.27.

The host name aspmx3.googlemail.com points to 2607:f8b0:4001:c70::1a and 192.178.209.27.

The host name aspmx.l.google.com points to 2607:f8b0:4004:c19::1b and 172.253.62.27.

The host name alt1.aspmx.l.google.com points to 2607:f8b0:4003:c30::1b and 74.125.27.26.

The host name alt2.aspmx.l.google.com points to 2607:f8b0:4001:c70::1a and 192.178.209.26.

Host names pointing to 2607:f8b0:4003:c30::1b are aspmx2.googlemail.com and alt1.aspmx.l.google.com.

Host names pointing to 2607:f8b0:4001:c70::1a are aspmx3.googlemail.com and alt2.aspmx.l.google.com.

Common IPs: 2607:f8b0:4003:c30::1b used by aspmx2.googlemail.com and alt1.aspmx.l.google.com; 2607:f8b0:4001:c70::1a used by aspmx3.googlemail.com and alt2.aspmx.l.google.com.