Simplifying DNS Lookup and Troubleshooting With Dot Net

Introduction

The Dot NET framework is one of the most widely used frameworks in web development and programming. Because it supports so many languages and is frequently updated by Microsoft, developers are comfortable knowing support won’t be dropped for it.

That matters a lot in the development world. Using outdated technologies means that your programs are unable to interface and work with modern ones.

DNS, or the Domain Name System, is another core system tied to the internet. It is the backbone of the internet because it provides all the necessary information for servers and clients to find each other and exchange resources.

If you are a Dot NET developer, sooner or later, you will need to deal with DNS on your own. Today, we will introduce you to a DNS client library that can work with any version of Dot NET. Let’s see how it can help you troubleshoot DNS problems.

What is DNS Client.NET?

DNS Client.NET is an open-source library for the .NET framework. It allows you to perform DNS lookups. It is typically used to query a network’s DNS server from within an application. You can also use it to query other DNS servers (those not on your network).

One thing to note is that DNS Client.NET only checks Google’s DNS servers for records. So, keep that in mind.

It is also cross-platform, so it can work with Linux and Mac in addition to Windows.

It is easy to install. You can use Nuget or the Dot NET CLI (command line interface) to install DNS Client.NET.

How to Do a DNS Lookup with DNS Client.NET?

The actual steps of conducting a DNS lookup are very easy. Just follow these steps to conduct a DNS lookup with DNS Client.NET.

Of course, the prerequisite is that you must have it installed first. Now, let’s see how you can do a lookup.

Initialize the Client

To initialize the client, you need to write the following code. We are going to use C# in our examples as it is one of the most often used languages when working with Dot NET.

    var client = new LookupClient();
    client.UseCache = true; 

However, if you want to use a customer DNS server running on a specific port, then you need to write this command instead.

    var endpoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 8600);
    var client = new LookupClient(endpoint);

Of course, the 8600 (port number) will need to be replaced with the actual port that you want to specify.

Anyway, that’s it for initialization.

2. Run a Query

Now, we have to run a query. Here, we have multiple choices. We can either specify the type of record that we want to look up, or we can look up all of them at once.

Here’s how you can look up specific records.

    var result = client.Query("domain.name.com", QueryType.A);

You can replace “A” with “Any” to include more records if you like.

3. Process Results

To find results, you will need to provide a command that returns and shows the value of the record.

Here’s how you can do it.

    foreach (var aRecord in client.Query("google.com", QueryType.A).Answers.ARecords())
{
    Console.WriteLine(aRecord.Address);
}

If everything is done correctly, you will see an output similar to this.

; (2 server found)
;; Got answer:
;; ->>HEADER<<- opcode: Query, status: No Error, id: 40346
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:

; EDNS: version: 0, flags:; UDP: 512; code: NoError
;; QUESTION SECTION:
doodoo.net.                      	IN 	A

;; ANSWER SECTION:
doodoo.net.                      	300 	IN 	A 	64.190.63.222

;; Query time: 39 msec
;; SERVER: 8.8.8.8#53
;; WHEN: Wed Oct 09 09:25:06 Z 2024
;; MSG SIZE  rcvd: 55