1. Install Oracle Client.
2. Install Oracle DBD.
3. Grant permission to the Unix box from the remote Oracle DB.

grant ALL ON DB.* to 'user'@'UNIX BOX IP' identified by 'password'
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4. Connect Oracle database by specifying the remote host.

use DBI;
$dbh = DBI->connect("DBI:mysql:host=IP ADDRESS;database=$dbname","user
+name","password");
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