Question backup server for plesk

[Kingsley]

Hello;

I want to setup a backup server. i am kinda confused how the setup will be made. here is what i understand.

I will get a high storage server then install an FTP program on it then add the FTP details on the server with plesk installed.

OR do i need to add the backupsy agent to my server with plesk installed? as stated here Initial Setup Guide - Knowledgebase - Backupsy

Please if you have any idea share with me.