Question How does redis work in plesk?

[Azurel]

Server operating system version

AlmaLinux 8.10 (Cerulean Leopard)

Plesk version and microupdate number

Plesk Obsidian 18.0.68#2

Hello,

in phpinfo() I see that redis is available. (Its installed by plesk and enabled in php settings.)
Redis Version: 6.1.0
Redis Sentinel Version: 1.0

But how do I access the redis server? I used:

if (class_exists(\Redis::class)) {
$this->redis = new \Redis();
$this->redis->connect('127.0.0.1', 6379);
}

connect() throw "Connection establishment rejected" (translated). I can't find a useful article on this. Can anyone here help me?
Change 127.0.0.1 to localhost not helped.

 

[Kaspar]

in phpinfo() I see that redis is available.

No. What you're seeing is the Redis extension for PHP, which is installed and enabled by default. The Redis extension can be used to easily connect to a Redis server via PHP. (Similar to how you would connect and use a MySQL database in PHP).

However you still need to install the Redis server yourself. Either by directly installing it on your Plesk server via the epel repository (for RHEL bases OSes), running it in a Docker container or installing it on a remote server.

 

[Azurel]

Thanks! I had found the article, but at first I understood it to mean that these were two alternative ways to set up Redis, not two steps you needed to perform both. I managed to get it working by adding Docker. Docker itself also creates a port mapping from 6379 to 32768, which is why you have to change the port to 32768 in PHP. Then the connection to Redis works.