Warning: session_start(): Cannot find save handler ‘redis’

I want to set php.ini to use Redis as session handler. I did it this way:

session.save_handler = redis
session.save_path = tcp://172.17.0.2:6379

My Php application and Redis are running in 2 different containers. This is the code I’m trying to run in Php:

<?php
if(!isset($_SESSION)){
        session_start();
}
?>

Due to my searchs I found that I should install:

sudo apt-get install php5-redis

but E: Unable to locate package php5-redis I’ve also tried: php-redis, php7-redis, php7.4-redis and the same result. Resutls for apt-cache search php | grep -i redis is:

libphp-predis - Flexible and feature-complete PHP client library for the Redis key-value store

What’s wrong?

Answer

You need use the pecl to install redis:

pecl install redis

More details is here

If you are using docker insert into Dockerfile:

RUN pecl install redis 
&& docker-php-ext-enable redis