Installation

Delete the current vHost directory:

sudo rm -r /www/grav.howto.ovh

Get Grav latest version and unzip it in /www:

wget -O ~/grav-admin-latest.zip https://getgrav.org/download/core/grav-admin/latest
sudo unzip -d /www/ ~/grav-admin-latest.zip
(optional) delete the archive:
rm ~/grav-admin-latest.zip
    

Move Grav install to the vHost

sudo mv /www/grav-admin /www/grav.howto.ovh

Adjust user rights:

sudo chown -R www-user:www-data /www/grav.howto.ovh
cd /www/grav.howto.ovh

And permissions:

find . -type f | sudo xargs chmod 664 && find ./bin -type f | sudo xargs chmod 775 && find . -type d | sudo xargs chmod 775 && find . -type d | sudo xargs chmod +s && umask 0002