fail2ban and Owncloud, cannot access logs of Owncloud

HI,

I followed the instruction for building Owncloud 10 on ubuntu 16.04 server and everything is working well, every clear instructions. However I thought it would be a good idea to add fail2ban to minimise the risk of attempted logins to Owncloud. During the process of building the serve, i found a document on Owncloud that said that you should increase the security on the data folder, so I ran the following command

sudo chown -R www-data:www-data /var/www/owncloud/ , it would appear that fail2ban or even sudo user cannot access the owncloud.log file as I have have applied the chown command, how can I resolve this issue without compromising the security of the server.

Any help or pointers will be greatly appreciated.

Steve