SOLVED OSSN MOD_REWRITE REQUIRED

just a simple note.

1. ensure that you php enable mod_rewtite by a2enmod rewrite
2. create file rewrite.php on base_dir, just put <?php print 1; ?>
3. ensure that your base_dir ossn directory setting as below : 

       <Directory "/var/www/html/ossn">
                DirectoryIndex index.php
                Options FollowSymLinks
                AllowOverride All
                Require all granted
        </Directory>

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