I followed this http://www.instructables.com/id/NextCloud-on-the-Raspberry-Pi-DIY-Dropbox/ But using a mounted folder in my Downloads folder eg /home/pi/Downloads/4TB/nextcloud. (Ext4)
I had trouble with permissions being mounted thru fstab with UUID (The preferred method blkid?).
I set permissions to 777 and the nextcloud gave error Files readable by all users set 0770.
When I used chmod 0770 the ocdata file was flagged as missing.
I also run a Pi-hole as well but I turned it off this time.
I think the solution for the install was chown -R www-data:www-data /home/pi/Downloads/4TB taken from https://help.nextcloud.com/t/changing-data-directory/11156/2 because of where the nextcloud data folder was. I have other files on my Ext USB Powered HDD
I am having trouble installing apt-get install php5-apc for the Pi 3 B, I have enabled backports and roundcube.
Currently doing a backup to another USB drive.