To make an alias to your domain, you can use the ServerAlias directive of apache server, in the file '/usr/local/apache/conf.d/vhosts.conf'.
If you have, for example:
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ServerAlias domainexample.com
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you can manually edit to:
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ServerAlias domainexample.com server2.domainexample.com
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or:
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ServerAlias domainexample.com server2.domainexample.com server3.domainexample.com
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or:
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ServerAlias *.domainexample.com
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etc.
The only question I have is, if editing manually, the changes would be overwritten by changes made via panel, ou updates.
Regards,
Netino