I was looking for a way to achieve this for several Virtual Machines: VirtualPrivateServer and local VirtualBox, in order to replace Dropbox and Rsync. These servers run backups creating tar.gz files from directories, sqldatabase dumps, and copy configuration and installation files, triggered by crontab. Space is limited so these files do not change name, they are overwritten and just their size and/or timestamp are changed. I used to manage versions on a local machine running BackInTime. Nextcloud has it's own version controle, so BackInTime is no longer required either.
With a NextCloudPi folder mounted permanently, I address all of the requirement in a single solution. Here is how I did it.
sudo apt-get install davfs2
Add a line to fstab using
sudo nano /etc/fstab
https://nextcloudpi.mydomain.org:xx43/remote.php/webdav/MYbackups/ /media/backups davfs defaults,uid=username,gid=groupname,_netdev,auto 0 0
Add your user to the correct group:
sudo usermod -a -G davfs2
sudo mkdir /media/backups
Add mountpoint, user and password to davfs2 configuration file
sudo echo “/media/backups/ username password” >> /etc/dav2fs/secrets
Mount the webdav folder
sudo mount /media/backups
Check if mounted
I now have an additional 80GB of space available to my virtual machine, so I can backup to my hearts content. I can also revert to any version by restoring it to a an earlier version from Nextcloud file manager.