sudo nano /etc/apt/sources.list

deb https://mirrors.tuna.tsinghua.edu.cn/raspbian/raspbian/ stretch main contrib non-free rpi

sudo apt-get install apache2

sudo apt-get install mysql-server

sudo vim /etc/apache2/apache2.conf

sudo mysql -u root -p
update mysql.user set plugin='mysql_native_password';
update mysql.user set password=PASSWORD("newpassword") where User='root';
flush privileges;

sudo apt-get install php5 php5-gd php-xml-parser php5-intl php5-sqlite php5-mysql smbclient curl libcurl3 php5-curl

sudo apt-get install phpmyadmin

sudo wget https://download.owncloud.org/community/owncloud-9.1.4.zip
sudo unzip owncloud-9.1.4.zip -d /var/www/html/
cd /var/www/html/owncloud
sudo mkdir data

sudo chown -R www-data:www-data data
sudo chown -R www-data:www-data config
sudo chown -R www-data:www-data apps

raspberryIP/owncloud