Troubleshooting DNS with dig and nslookup

When your domain is not resolving correctly, two of the most useful tools for diagnosing DNS issues are dig (on Linux/macOS) and nslookup (on Windows). These tools let you query DNS servers directly to see how your domain is configured.

Why Use These Tools?

Verify if your domain points to the correct IP address.
Check if DNS propagation is complete.
Inspect specific DNS records (A, MX, CNAME, TXT, etc.).
Identify misconfigurations between your registrar and hosting provider.

Using Web-Based DNS Tools

If you’re not comfortable with the command line, you can use free online tools:

whatsmydns.net → Check global DNS propagation.
digwebinterface.com → Run dig queries online.

Using `nslookup` on Windows

Open Command Prompt.
Run a basic query:
Terminal window
```
nslookup example.com
```
→ Shows the IP address (A record) for the domain.
Query a specific DNS server→
Terminal window
```
nslookup example.com 8.8.8.8
```
Uses Google DNS (8.8.8.8) instead of your default resolver.
Look up MX (mail) records:
Terminal window
```
nslookup
set type=MX
example.com
```

Using dig on Linux/macOS

Open Terminal.
Run a basic query:
Terminal window
```
dig example.com
```
→ Displays the A record for the domain.
Query a specific DNS server:
Terminal window
```
dig @8.8.8.8 example.com
```
Look up MX records:
Terminal window
```
dig example.com MX
```
Look up TXT records (useful for SPF/DKIM):
Terminal window
```
dig example.com TXT
```

Interpreting Results

ANSWER SECTION → Shows the record returned (e.g., IP address for A record).
AUTHORITY SECTION → Shows which nameservers are authoritative for the domain.
ADDITIONAL SECTION → May include related records (like IPs of nameservers).