Use Mod_Rewrite to Rewrite ROOT to Another Path

apache .htaccess mod-rewrite url-rewriting

A correct redirect of the root path is simply :

RewriteEngine OnRewriteRule ^/$ /page [R]

to force this only on one subdomain (which should barely happen if your rewrite block is in a virtualhost definition) :

RewriteEngine onRewriteCond %{HTTP_HOST} =subdomain.example.comRewriteRule ^/$ /page [R]

apache .htaccess mod-rewrite url-rewriting

Copying my deleted response:

In htaccess of your documentroot simply:

RewriteEngine onRewriteCond %{HTTP_HOST} =subdomain.example.comRewriteRule ^$ /page

apache .htaccess mod-rewrite url-rewriting

You have two options to rewrite your root to another path,

Mod-rewrite:

RewriteEngine onRewriteRule ^/?$ /anotherPath [L]

You can use one of the above options to internally redirect example.com/ to example.com/anotherPath.

References:

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