Asume that you have PHP7 already installed.
All steps as following :
1. Dowload PhpRedis
cd /tmp
wget https://github.com/phpredis/phpredis/archive/master.zip -O phpredis.zip
2. Unpack, compile and install PhpRedis
unzip -o /tmp/phpredis.zip && mv /tmp/phpredis-* /tmp/phpredis && cd /tmp/phpredis && phpize && ./configure && make && sudo make install
3. Now it is necessary to add compiled extension to php config
Add PhpRedis extension to PHP 7.
Use proper path to your php configs e.g. /etc/php/7.0/ , /etc/php/7.1/
sudo touch /etc/php/7.0/mods-available/redis.ini && echo extension=redis.so > /etc/php/7.0/mods-available/redis.ini
sudo ln -s /etc/php/7.0/mods-available/redis.ini /etc/php/7.0/apache2/conf.d/redis.ini
4. Restart PHP-FPM if you have PHP 7
sudo service php7.0-fpm restart
5. Restart Apache
sudo service apache2 restart
check status of apache2
sudo systemctl status apache2
