A standard DNS subdomain record has a corresponding name such as blog.example.com. However, sometimes it may be necessary to enable Wildcard DNS which does not have a single record assigned. Instead of appearing as blog.example.com (or any other subdomain), it appears as *.example.com. The * character is used to match non-existing subdomain names.
Simply put, Wildcard DNS is used to provide DNS records for subdomains that do not exist.
Wildcard DNS is separate from Wildcard SSL certificates. It's currently not possible to use a Wildcard SSL certificate at DreamHost. View the following article for further details.
How can I use a Wildcard DNS at DreamHost?
You can implement Wildcard DNS for domains that are running only on a DreamHost Virtual Private Server (VPS) or Dedicated Server. This is due to the extremely high resource usage (and potential abuse) that usually comes with installing software that relies on Wildcard DNS in order to function (i.e., WordPress Multi-User, or WPMU, and others).
DreamHost may, in special cases, set this up for a customer. This is a manual procedure for the support staff so please make sure that it's something that you absolutely need and that the domain in question is currently running on a VPS or Dedicated Server before requesting it. Please also make sure that you're aware of the technical implications of having a wildcard DNS entry set up on your domain.
Unmanaged option using DreamCompute
The above configurations only apply to VPS and Dedicated Servers which are managed by DreamHost. You also have the option of creating a cloud server using DreamCompute, DreamHost's cloud computing service.
When you create a DreamCompute instance, you have full control over the server meaning you are able to install anything you like on it.
After you point your website to your DreamCompute instance, you can then add a wildcard DNS entry in your DreamHost panel. Any additional configurations must be done by logging into your DreamCompute instance.
However, please note that technical support is unable to assist in any way with customizations made to a cloud server. If you choose to use this option, you must be ready to install all software and troubleshoot any issues that may arise from it.
If you need support
If you need Wildcard DNS set up for your domain, submit a support ticket on the Contact Support page.