Mirror domain overview

 

Overview

This article explains what a domain Mirror is and how to configure this at DreamHost.

Background

A domain mirror allows you to see the content of one of your websites on another website's URL. It functions as follows:

  1. You upload your content to Site A.
  2. Site B (on the same DreamHost account) is then configured to mirror Site A.
  3. Site B then displays the content of Site A.

This allows you to access the same DreamHost site content under more than one address. For example, you can have a .com and a .net site that share the same content or access your site live before your domain is set up.

Custom DNS records must be removed

If your domain is currently set as 'DNS Only' and you wish to change it to a Mirror, first check to see if you have previously added any custom A or CNAME records to the domain. If so, these need to be removed as they will conflict with the new configuration.

FAQs

Can I use a mirror on an external domain?

No. A mirror domain can only "mirror" an existing domain hosted at DreamHost, as it is a server alias, not a physical mirror, and there is no content duplication involved. If your domain is registered at another company, you must point its DNS records to DreamHost to create a mirror.

Will a mirror work with any type of website?

Mirrored domains do not work well or at all with the following:

  • Some CMS applications (such as WordPress) — This is because some CMS applications hard-code the URL for the site and actively rewrite the URL in the browser address bar, which prevents website links from functioning on the mirror site.
  • DreamPress — A mirror of a DreamPress site will not work in most cases due to DreamPress caching.

Will the mirror domain work with https?

No. If the site is mirroring a domain with an SSL certificate, the mirror site will throw an error when visited. For example:

  • You configure mirror.example.com to mirror https://example.com.
  • When you visit mirror.example.com, the URL changes to https://mirror.example.com.
  • The browser then throws an error since the SSL certificate is not installed on mirror.example.com. This occurs because each website must have its own unique SSL certificate installed.

Will my website links still work?

Website links to other pages on the original URL address only function if they do NOT contain the domain name. This is called using a Relative path. Here is an example of how Relative paths differ from Absolute paths:

  • Relative: /about-us.html
    This keeps the visitor on the mirror URL.
  • Absolute: https://www.example.com/about-us.html
    This takes the visitor away from the mirror URL. If you require absolute paths in your links, a redirect should be used instead.

How to configure a Mirror domain

This section explains how to create or disable a Mirror.

DNS propagation

Please note that Mirroring is the same as any other DNS change. This means the DNS changes must propagate first before the mirror functions online. In general, this shouldn't take any longer than 6 hours. You can keep track of when the new DNS records update in different locations using either of the following links:

Creating a Mirror (on a new domain)

  1. Navigate to the Manage Websites page.
  2. Click the Add Website button.
  3. Select one of the options to create or add a domain, then click the Next: Hosting button.
  4. Under the Non-Hosted section, click the Mirror Domain option.
  5. Select the domain you'd like to mirror and then click the Mirror Domain button.

Changing to a Mirror (on an existing domain)

  1. Navigate to the Manage Websites page.
  2. Click the Manage button to open the Domain Settings page, which allows you to adjust various settings for your site.
    • If in Grid view, click the Manage button at the bottom of the website box.
    • If in List view, click the Manage button at the far right of your domain name.
  3. Select the Settings tab.
  4. Scroll down to the Non-Hosting Options section.
  5. Click the Mirror Domain subsection.
  6. Select the domain you'd like to mirror and then click the Mirror Domain button.

Disabling a Mirror

To disable a mirror, you just need to change the hosting configuration to another option, such as Fully Hosted or DNS Only.

See also

Did this article answer your questions?

Article last updated PST.

Still not finding what you're looking for?