> For the complete documentation index, see [llms.txt](https://ajmal-anwar.gitbook.io/zyberspace-by-ajmal/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ajmal-anwar.gitbook.io/zyberspace-by-ajmal/zyberlab/06-network-security-basics/dns-testing.md).

# DNS Testing

DNS is essential to Active Directory because domain members depend on it to locate domain services.

## Objective

Use simple DNS tests to confirm that `CLIENT01` can resolve the ZyberLab domain and the `DC01` hostname.

## Check DNS Configuration on CLIENT01

Open Command Prompt and run:

```
ipconfig /all
```

Confirm that the preferred DNS server points to the lab DNS service on `DC01`.

## Test the Domain Controller Name

Run:

```
nslookup DC01
```

Then test the fully qualified name:

```
nslookup DC01.zyberlab.test
```

The exact output depends on the DNS records in your lab.

## Test the Lab Domain

Run:

```
nslookup zyberlab.test
```

Review the response and note which DNS server answered the request.

## Test from Kali Linux

On `KALI01`, you can run:

```
nslookup DC01.zyberlab.test <DC01-IP>
```

This explicitly sends the query to the lab DNS server.

## What to Check if Resolution Fails

Confirm that:

* `DC01` is running
* The DNS service is running
* `CLIENT01` uses `DC01` for domain DNS
* The hostname or domain name is typed correctly
* The systems can reach each other over the lab network

## Verification

The lab is complete when you can resolve the domain controller name and explain which DNS server answered the query.

## Security Relevance

Many authentication and domain problems begin with DNS issues. DNS activity can also provide useful evidence when investigating which services or hosts a system attempted to contact.