You can run the same site in different domains

Yes, it does. But do not do that.

Why not use the "same site" in multiple domains?

Because of indexing and other Google rules.

That's why Google strictly treats duplicate content on the Internet, incorrect notes and missing pages / content (HTTP 404), or duplication of content.

What is the right way to do this?

Permanent redirect: HTTP 301

In short, what this means: You're saying that every time a user accesses www.seusite.com.br you want to redirect it to www.seusiteoficial.com.br in a PERMANENT way.

  Google recommends using HTTP 301 redirection to change the URL of a page that is displayed in search results thus avoiding HTTP 404

Then it would look like this: when the user enters the sites:

• www.site1.com
• www.site2.com.br
• www.site3.com.br

It will be redirected to:

• www.sitecorreto.com.br

That's the right way.

How do I do this?

There are several options:

• .htaccess (Apache mod_rewrite )
• VirtualHost
• Redirecting your own application / framework
• Panel of your hosting: Cpanel / Plesk

Example with .htaccess

Options +FollowSymLinks
RewriteEngine on
Redirect 301 / http://www.seusiteoficial.com.br/

This .htaccess should be placed at the root of each site / domain .

I recommend

• Shared Hosting: panel redirection (Cpanel / Plesk)
• Cloud / VPS: redirection by <VirtualHost> of Apache or through a similar configuration in Nginx or HHVM.

Depends on locaweb has many flaws (at least with me) but this option exists.

Domain Registration > Change Domain > here is a 'change browser address' option

Check your hosting service for anything similar.

Att

The company that has registered your domains will probably have an administrative panel where you can configure how they work.

Within the settings you can choose options such as redirect multiple domains to a single master domain or redirect all to the same IP address. So everyone goes to the same site using just one FTP.

In case of doubt on how to do this, I recommend contacting the company that hired the domains, as the step by step setup can change from one panel to another.