# DNS Configuration

## Reserved Subdomains

{% hint style="warning" %}
This is a partial list.

See also: [**Reserved Form Names**](https://help.form.io/faq/faq#are-there-any-restrictions-when-naming-a-form-or-resource)
{% endhint %}

These subdomains are utilized by \<form.io>, attempting to use one of them will result in issues with your portal.

* test
* www
* api
* help
* support
* portal
* formio
* app
* apps
* classic
* beta
* project
* storage
* dropbox
* atlassian
* available
* analytics
* team
* files
* pdf
* manager
* cdn
* alpha
* gamma