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1. With 301 redirect everything will be fine. It is normal method 
 
2. No, Google will think that those domains are mirrors
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1. With 301 redirect everything will be fine. It is normal method

2. No, Google will think that those domains are mirrors

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<div class="content wysiwyg-content">
Hello Experts, 
 
I have registred 4 different domains: 
 
testdomain.de 
testdomain.ch 
testdomain.at 
testdomain.com 
 
Currently all Domains are redirected to the same Host, so a visitor gets the same content whatever domain he uses. 
 
I would like to change that now - i only want to the use the testdomain.COM as the main domain, and redirect like the following: 
 
testdomain.de --&gt; de.testdomain.com 
testdomain.ch --&gt; ch.testdomain.com 
testdomain.at --&gt; at.testdomain.com 
 
My questions are the following: 
 
1. How can I realize that regarding that I want my indexed google links to work also in the future. I read sth about a 301 redirect but I´m not sure about that. 
 
2. Will Google regard my content as duplicate content, since i still have the same content on 
 
ch.testdomain.com 
and 
de.testdomain.com 
and 
at.testdomain.com 
(and also of course testdomain.com itself)
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</div>

Hello Experts,

I have registred 4 different domains:

testdomain.de
testdomain.ch
testdomain.at
testdomain.com

Currently all Domains are redirected to the same Host, so a visitor gets the same content whatever domain he uses.

I would like to change that now - i only want to the use the testdomain.COM as the main domain, and redirect like the following:

testdomain.de --> de.testdomain.com
testdomain.ch --> ch.testdomain.com
testdomain.at --> at.testdomain.com

My questions are the following:

1. How can I realize that regarding that I want my indexed google links to work also in the future. I read sth about a 301 redirect but I´m not sure about that.

2. Will Google regard my content as duplicate content, since i still have the same content on

ch.testdomain.com 
and
de.testdomain.com
and
at.testdomain.com
(and also of course testdomain.com itself)

301 redirect / Duplicate Content

The Apache HTTP Server is a secure, efficient and extensible server that provides HTTP services in sync with the current HTTP standards. Typically Apache is run on a Unix-like operating system, but it is available for a wide variety of operating systems, including Linux, Novell NetWare, Mac OS-X and Windows. Released under the Apache License, Apache is open-source software.

Apache Web Server

The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems. Hypertext is structured text that uses logical links (hyperlinks) between nodes containing text. HTTP is the protocol to exchange or transfer hypertext. HTTP functions as a request-response protocol in the client-server computing model. HTTP is designed to permit intermediate network elements to improve or enable communications between clients and servers. HTTP is an application layer protocol designed within the framework of the Internet Protocol Suite; it presumes an underlying and reliable transport layer protocol.