course-db.com - dns.ninja
course-db.com
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.netnstld@verisign-grs.com serial=1785510682 | ||||||
MX for
course-db.com |
Same first word
course-db.com |
Similar names
DNS History
13 records (7 active, 6 former)
●NSns1.xserver.jp2026-02-28 → 2026-07-31 · 3 obs
● 2026-02-28 20:07:56
● 2026-07-31 15:15:18
●NSns2.xserver.jp2026-02-28 → 2026-07-31 · 3 obs
● 2026-02-28 20:07:56
● 2026-07-31 15:15:18
●NSns3.xserver.jp2026-02-28 → 2026-07-31 · 3 obs
● 2026-02-28 20:07:56
● 2026-07-31 15:15:18
●NSns4.xserver.jp2026-02-28 → 2026-07-31 · 3 obs
● 2026-02-28 20:07:56
● 2026-07-31 15:15:18
●NSns5.xserver.jp2026-02-28 → 2026-07-31 · 3 obs
● 2026-02-28 20:07:56
● 2026-07-31 15:15:18
○NSns57.domaincontrol.com2008-03-07 → 2015-06-23 · 4 obs
● 2015-06-23 11:59:56
○ 2015-11-06 20:56:22
○ 2026-07-31 15:15:18
○NSns58.domaincontrol.com2008-03-07 → 2015-06-23 · 4 obs
● 2015-06-23 11:59:56
○ 2015-11-06 20:56:22
○ 2026-07-31 15:15:18
●MXcourse-db.com2026-02-28 → 2026-07-31 · 3 obs
● 2026-02-28 20:07:56
● 2026-07-31 15:15:18
○MXmailstore1.secureserver.net2008-03-07 → 2015-06-23 · 4 obs
● 2015-06-23 11:59:56
○ 2015-11-06 20:56:22
○ 2026-07-31 15:15:18
○MXsmtp.secureserver.net2008-03-07 → 2015-06-23 · 4 obs
● 2015-06-23 11:59:56
○ 2015-11-06 20:56:22
○ 2026-07-31 15:15:18
●A162.43.94.652026-02-28 → 2026-07-31 · 3 obs
● 2026-02-28 20:07:56
● 2026-07-31 15:15:18
○A50.63.202.602015-06-23 → 2015-06-23 · 4 obs
● 2015-06-23 11:59:56
○ 2015-11-06 20:56:22
○ 2026-07-31 15:15:18
○A68.178.232.1002008-03-07 → 2008-03-07 · 3 obs
○ 2015-06-23 11:59:56
○ 2026-07-31 15:15:18
🔍 DNS Trace
📋 Delegation Chain
| Zone | Nameservers | Glue |
|---|---|---|
| com | e.gtld-servers.net, b.gtld-servers.net, l.gtld-servers.net, j.gtld-servers.net... | - |
| course-db.com | ns1.xserver.jp, ns2.xserver.jp, ns3.xserver.jp, ns4.xserver.jp... | - |
✅ Authoritative Response
Server:202.226.36.247
NS records: ns1.xserver.jp, ns2.xserver.jp, ns3.xserver.jp, ns4.xserver.jp, ns5.xserver.jp
🔒 DNSSEC Status
⚠️ Insecure (no DNSSEC)
No DS record for course-db.com (unsigned zone)
⏱️ Timing
Total: 1138ms | Queries: -
📄 Records
| Type | Count | Sample Data |
|---|---|---|
| A | 1 | 162.43.94.65 |
| NS | 5 | ns3.xserver.jp, ns1.xserver.jp... |
| MX | 1 | course-db.com (pri: 0) |
| TXT | 1 | v=spf1 +a:sv15064.xserver.jp +a:course-d |
| SOA | 1 | ns1.xserver.jp root.xserver.jp |
Analysis
Mail Server Role
course-db.com acts as its own mail server.
IP Addresses
course-db.com points to a single IP number: 162.43.94.65.
Additional host names — ns.orchidcc.com, www.yamagata-melco.co.jp, best-ryoushoku.jp and two others — share IP numbers with course-db.com.
Name Servers
Delegation for course-db.com is to five name servers: ns1.xserver.jp, ns2.xserver.jp, ns3.xserver.jp and two others.
At least some of course-db.com's name servers are shared with other domains, for example uranai365.jp, visa110.com, ike-navi.com and two more.
These name servers tend to be deployed in combination with the name servers ns4.xserver.jp and ns5.xserver.jp.
Host names with three IP numbers:
ns1.xserver.jp has IP addresses 202.226.36.164, 202.226.36.170 and 202.226.36.246.
ns4.xserver.jp has IP addresses 183.90.224.226, 183.90.224.230 and 202.226.39.247.
ns5.xserver.jp has IP addresses 157.112.182.218, 157.112.182.220 and 202.226.37.247.
Host names pointing to a single IP address:
ns2.xserver.jp directs to 35.72.43.26.
ns3.xserver.jp directs to 202.226.36.247.
Mail Servers
course-db.com has a single mail server: course-db.com itself.
course-db.com has exactly one IP number: 162.43.94.65.