Using X-Sendfile
After enabling mod_xsendfile Apache module, to enable the X-Sendfile header you will need to add the following to your Apache vhost, where XSendFilePath is the downloads directory:
<IfModule xsendfile_module>
XSendFile on
XSendFilePath <install_path>/var/downloads
XSendFilePath <install_path>/var/meetings
<IfModule headers_module>
RequestHeader set X-Sendfile-Type X-Sendfile
</IfModule>
</IfModule>
Replace <install_path> with the path to your installation.
The header will then need enabling in Jadu Central by setting XSENDFILE_ENABLED is set to true within the JaduConstants database table.