##### Just run the script with parameter - url to the latest version #####

if [ -z "$1" ]
then
echo "Error input..."
echo "Use sudo ./runOwncloudUpdate.sh [link to the latest version of owncloud]"
exit 0
fi

echo "Switch to the maintance mode..."
sudo -u www-data php /var/www/html/owncloud/occ maintenance:mode --on

echo "Stop the web server apache..."
sudo service apache2 stop

echo "Backuping ownCloud directory..."
now=$(date +'%m_%d_%Y')
sudo mv /var/www/html/owncloud /var/www/html/backup_owncloud_${now}

echo "Downloading the latest version..."
sudo wget $1

echo "Backuping owncloud database..."
sudo mysqldump --single-transaction -h localhost -u root -p $2 owncloud > owncloud-dbbackup_${now}.bak

echo "Extracting..."
sudo tar -xf /var/www/html/owncloud-complete-latest.tar.bz2

echo "Copying config..."
sudo cp /var/www/html/backup_owncloud_${now}/config/config.php /var/www/html/owncloud/config/config.php

echo "Copying data directory..."
sudo cp -r /var/www/html/backup_owncloud_${now}/data /var/www/html/owncloud/data

echo "Giving read permission..."
sudo chown -R www-data:www-data /var/www/html/owncloud

echo "Upgrading owncloud..."
sudo -u www-data php /var/www/html/owncloud/occ upgrade

echo "Copying apps folder..."
sudo cp -r /var/www/html/backup_owncloud_${now}/apps-external /var/www/html/owncloud/

echo "Disable maintenance mode..."
sudo -u www-data php /var/www/html/owncloud/occ maintenance:mode --off

echo "Upgrade is done sucesfully!"
echo "Run apache server..."
sudo service apache2 start

OwnCloud update script on your onpremis server (apache)