123b.courses - robtex.com
123b.courses
| DNSSEC | ⚠️ Not signed | ||||||
| A | 2606:4700:3034::ac43:d1d3🇺🇸 Cloudflare2606:4700:3034::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints | ||||||
| A | 2606:4700:3037::6815:5d77🇺🇸 Cloudflare2606:4700:3037::/48 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints | ||||||
| A | 104.21.93.119Cloudflare104.21.80.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints | ||||||
| A | 172.67.209.211🇺🇸 Cloudflare172.67.208.0/20 , Inc. 101 Townsend Street, San Francisco, California 94107, US ✓ In HTTPS hints | ||||||
| NS | alec.ns.cloudflare.com ⭐ | ||||||
| A | 2606:4700:58::adf5:3b3b🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | alec.ns.cloudflare.com | ||||||
| A | 2803:f800:50::6ca2:c13b🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L | ||||||
| PTR | alec.ns.cloudflare.com | ||||||
| A | 2a06:98c1:50::ac40:213b🇺🇸 Cloudflare2a06:98c1:50::/45 | ||||||
| PTR | alec.ns.cloudflare.com | ||||||
| A | 108.162.193.59🇺🇸 Cloudflare108.162.193.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | alec.ns.cloudflare.com | ||||||
| A | 172.64.33.59🇺🇸 Cloudflare172.64.33.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | alec.ns.cloudflare.com | ||||||
| A | 173.245.59.59🇺🇸 Cloudflare173.245.59.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | alec.ns.cloudflare.com | ||||||
| NS | irma.ns.cloudflare.com | ||||||
| A | 2606:4700:50::adf5:3aa6🇺🇸 Cloudflare2606:4700:50::/44 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | irma.ns.cloudflare.com | ||||||
| A | 2803:f800:50::6ca2:c0a6🇨🇷 Cloudflare2803:f800:50::/45 LACNIC generated route6 for CloudFlare Latin America S.R.L | ||||||
| PTR | irma.ns.cloudflare.com | ||||||
| A | 2a06:98c1:50::ac40:20a6🇺🇸 Cloudflare2a06:98c1:50::/45 | ||||||
| PTR | irma.ns.cloudflare.com | ||||||
| A | 108.162.192.166🇺🇸 Cloudflare108.162.192.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | irma.ns.cloudflare.com | ||||||
| A | 172.64.32.166🇺🇸 Cloudflare172.64.32.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | irma.ns.cloudflare.com | ||||||
| A | 173.245.58.166🇺🇸 Cloudflare173.245.58.0/24 , Inc. 101 Townsend Street, San Francisco, California 94107, US | ||||||
| PTR | irma.ns.cloudflare.com | ||||||
| HTTPS | HTTP/3, HTTP/2 ✓ hints match | ||||||
| IPv4 | 104.21.93.119, 172.67.209.211 | ||||||
| IPv6 | 2606:4700:3034::ac43:d1d3, 2606:4700:3037::6815:5d77 | ||||||
| SOA | alec.ns.cloudflare.comdns@cloudflare.com serial=2395787513 | ||||||
courses
| DNSSEC | 🔒 Signed (DS record present) | ||||||
| NS | a.nic.courses ⭐ | ||||||
| NS | b.nic.courses | ||||||
| NS | c.nic.courses | ||||||
| NS | x.nic.courses | ||||||
| NS | y.nic.courses | ||||||
| NS | z.nic.courses | ||||||
| SOA | a.nic.coursesadmin@tldns.godaddy serial=1774489270 | ||||||
rank #6 in the tld
this domain is a valid DNS name with the label 123b and the suffix .courses. The label 123b uses digits and letters, which is allowed. Whether it resolves depends on registration and DNS configuration; it would need to be registered and pointed to hosting.
Same first word
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132b.cn |
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DNS History
6 records (6 active, 0 former)
●NSalec.ns.cloudflare.com2026-03-18 → 2026-03-26 · 2 obs
● 2026-03-26 05:19:48
●NSirma.ns.cloudflare.com2026-03-18 → 2026-03-26 · 2 obs
● 2026-03-26 05:19:48
●A104.21.93.1192026-03-18 → 2026-03-26 · 2 obs
● 2026-03-26 05:19:48
●A172.67.209.2112026-03-18 → 2026-03-26 · 2 obs
● 2026-03-26 05:19:48
●A2606:4700:3034::ac43:d1d32026-03-18 → 2026-03-26 · 2 obs
● 2026-03-26 05:19:48
●A2606:4700:3037::6815:5d772026-03-18 → 2026-03-26 · 2 obs
● 2026-03-26 05:19:48
🔍 DNS Trace
📋 Delegation Chain
| Zone | Nameservers | Glue |
|---|---|---|
| courses | a.nic.courses, b.nic.courses, c.nic.courses, x.nic.courses... | 12 records |
| 123b.courses | alec.ns.cloudflare.com, irma.ns.cloudflare.com | - |
✅ Authoritative Response
Server:172.64.33.59
NS records: alec.ns.cloudflare.com, irma.ns.cloudflare.com
🔒 DNSSEC Status
⚠️ Insecure (no DNSSEC)
No DS record for 123b.courses (unsigned zone)
⏱️ Timing
Total: 799ms | Queries: -
📄 Records
| Type | Count | Sample Data |
|---|---|---|
| A | 2 | 104.21.93.119, 172.67.209.211 |
| AAAA | 2 | 2606:4700:3037::6815:5d77, 2606:4700:3034::ac43:d1d3 |
| NS | 2 | alec.ns.cloudflare.com, irma.ns.cloudflare.com |
| HTTPS | 1 | {"priority":1,"target":".","alpn":["h3", |
| SOA | 1 | alec.ns.cloudflare.com dns.cloudflare.co |
📌 Glue Records Collected
Total: 12
In-bailiwick: 12 (a.nic.courses, b.nic.courses, c.nic.courses...)
Analysis
IP Addresses
123b.courses points to four IP numbers: 2606:4700:3034::ac43:d1d3, 2606:4700:3037::6815:5d77, 104.21.93.119 and 172.67.209.211.
Other host names including g471.com, jakicukier.pl, signaturecreationbd.com, grcprimebath.com and mail.snd.co.id share IP numbers with 123b.courses.
Name Servers
123b.courses's delegation uses two name servers, alec.ns.cloudflare.com and irma.ns.cloudflare.com.
123b.courses shares the same name server setup as other domains, for example aidj.org, g28.company, zinc.email, jchook.com and mandat.is.
123b.courses at least partially shares name servers with other domains, including kevea.cloud, artwebhosting.com, line-pc.net, kokomo.fr and datingcheck69.com.
These name servers are commonly used with nitin.ns.cloudflare.com and violet.ns.cloudflare.com.
Host names with six IP numbers:
alec.ns.cloudflare.com points to: 2606:4700:58::adf5:3b3b, 2803:f800:50::6ca2:c13b, 2a06:98c1:50::ac40:213b, 108.162.193.59, 172.64.33.59 and 173.245.59.59.
irma.ns.cloudflare.com points to: 2606:4700:50::adf5:3aa6, 2803:f800:50::6ca2:c0a6, 2a06:98c1:50::ac40:20a6, 108.162.192.166, 172.64.32.166 and 173.245.58.166.