Backup for multiple filesystems!

I have sucsessfully installed the urbackup Server on one of my raspberry pi’s and it seems to work. On another raspberry pi I installed the client with btrfs-support. On the SD-Card where is the system installed is the filesystem EXT4. I have mounted an usb-hdd with filesystem btrfs. I would like to backup some subvolumes from the usb-hdd and from the system the /etc-directory. During the backup there are some errors that couldn’t create snapshots because filesystem EXT4.
Can I choose a backupfolder which is snapshoted (BTRFS) and not (EXT4)?
How can i change the client to normal mode (without btrfs snapshots)?

After a server install, the location of your client’s backup files is saved in
/etc/default/backupfolder and in /var/urbackup/backupfolder.

You can stop your server, create a btrfs filesystem in a different partition or LVM logical volume, move your data into that new btrfs-formatted partition or LV, then mount that btrfs-formatted partition/LV at either the old location (stored in those backupfolder files) or in a new location (after changing those 2 files). Don’t forget to update your