Configure PHP

Check the file has the same values for the parameters shown next, but leave the rest of the parameters with their default values.

/etc/php/7.0/fpm/pool.d/www.conf:
---------------------------------
user = www-data
group = www-data
listen = /run/php/php7.0-fpm.sock
listen.owner = www-data
listen.group = www-data
listen.mode = 0660

_$: systemctl restart php7.0-fpm.service

Once restarted, check the socket has been created with the proper permissions:

_$: ll /run/php
total 4
drwxr-xr-x  2 www-data www-data  80 Mar 18 13:08 ./
drwxr-xr-x 25 root     root     840 Mar 18 12:56 ../
-rw-r--r--  1 root     root       5 Mar 18 13:08 php7.0-fpm.pid
srw-rw----  1 www-data www-data   0 Mar 18 13:08 php7.0-fpm.sock=