Is it possible to set the path in which ISP Config should make the backups? Also, is it possible to use a remote path (ssh or ftp with rsync) for the backups?
Yes. Tools -> Server Config -> Your server -> Backup path. You can mount a remote server and then backup to that location.
Oh, I see. Thank you! This way I can't really use rsync, right? I should use something like sshfs and let ISP Config use cp (or whatever it's using).
You can use Rsync if you want to have a copy of the backups on the local hard disk too. If backups shall be stored remotely only, then you need a fs that can be mounted over the network into the backup folder.
To prevent opening new thread, I will ask here: What about /backup directory inside web site path? Is that not in use anymore? I would like to permit user's access to those backups to automatically download via FTP or SSH, but I would not like to give them access to /var/backups. Any idea?
Thats the place where the backup is made available to the client when you request it in the interface. That's why no symlinks are used and that's what ispconfig implements already with the button to make the backup avaiable in the backup list.