---
title: "DNS Override Overriding IP address for a Domain"
slug: "dns-override-overriding-ip-address-for-a-domain-1"
updated: 2023-01-06T15:49:41Z
published: 2023-01-06T15:49:41Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.catchpoint.com/llms.txt
> Use this file to discover all available pages before exploring further.

# DNS Override Overriding IP address for a Domain

## Overview

Catchpoint provides you with the ability to **override the DNS resolution** for a specific domain by specifying an IP address other than the one contained in the DNS records for the domain. The end result is similar to what you can do on your own PC when modifying the **Host File**.

This feature allows you to test the performance of a new server, data center, or CDN, without requiring changes in the DNS configuration or new testing domains. You can also use the feature to simulate slowness or inability to establish TCP connections on particular hosts.

** When this override is enabled for the Chrome monitor, the DNS time metric will show "0"*

## Steps

**To use the "DNS Override" feature, please follow the steps below:**

1. Edit the properties of the test, or folder, or Product.
2. In the **Request** section, select **Override**. ![dns0.png](https://cdn.document360.io/cb4af8f9-6751-4fd2-b39c-07aae832badb/Images/Documentation/360092162371-dns0.png)
3. Click on **Add HTTP Request Headers**.
4. Select **Child Host** in the **Apply To** field. ![dns_ch.png](https://cdn.document360.io/cb4af8f9-6751-4fd2-b39c-07aae832badb/Images/Documentation/360092162391-dns_ch.png)
5. Specify the exact domain in the **Apply to** field (Regular Expressions are *not* supported for DNS Override).
6. Select **(DNS Override)** in the **Field** option list.
7. In the **Value** field, specify the **IP address** to utilize for all the requests to this domain. (Macros are not supported, and only one IP can be specified).

**You can also utilize DNS Override in a Selenium script for Transaction tests. The format is:**

`setHeader(dns-override:<Domain_to_Match>,<IP_Address_to_Use>)`

## Example

`open(www.site.com) setHeader(dns-override:www.site.com, 12.12.15.25)`