Subdomain alias with htaccess
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I have this code for managing a subdomain alias: browsing sub.domain.com it shows domain.com/fp/sub.

    RewriteCond %{HTTP_HOST} ^sub\.domain\.com$
    RewriteRule (.*) /fp/sub/$1

I have a lot of these subdomain to setup. Is there a way to automate this process placing some variables instead of the correct subdomain/folder name?

I tried this code with no success

    RewriteCond %{HTTP_HOST} ^(sub1|sub2)\.domain\.com$
    RewriteRule (.*) /fp/$1/$2