---
title: "Which Domains to Whitelist in Restrictive Firewalls"
canonical: "https://documentation.chaos.com/space/COSMOS/125081402/Which%20Domains%20to%20Whitelist%20in%20Restrictive%20Firewalls"
format: markdown
---
<span style="color: #172b4d">For some clients with restrictive firewalls, the Chaos domains should be whitelisted (allow-listed).</span>

<span style="color: #172b4d"> </span>

## **Overview**

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<span style="color: #1c1c1c">An error page is present instead of the Cosmos Browser if the firewall is restricted.</span>

<span style="color: #172b4d"> </span>

## **How to fix it?**

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<span style="color: #172b4d">The following domains should be whitelisted in restrictive firewalls:</span>

- <span style="color: #172b4d">*.</span><span style="color: #172b4d">[chaos.com](http://chaos.com)</span>
- <span style="color: #172b4d">*.</span><span style="color: #172b4d">[chaosgroup.com](http://chaosgroup.com)</span>

This allows you to use Cosmos Browser.