Redis & clusters : how to configure cluster for cache ?

After many tries, I think I got a working config by moving the cache key under clusters :

'redis' => [

        'client' => env('REDIS_CLIENT', 'phpredis'),

        'options' => [
            'cluster' => env('REDIS_CLUSTER', 'redis'),
            'prefix' => env('REDIS_PREFIX', Str::slug(env('APP_NAME', 'laravel'), '_') . '_database_'),
        ],

        'default' => [
            'url' => env('REDIS_URL'),
            'host' => env('REDIS_HOST', '127.0.0.1'),
            'password' => env('REDIS_PASSWORD', null),
            'port' => env('REDIS_PORT', '6379'),
            'database' => env('REDIS_DB', '0'),
        ],

//        'cache' => [
//            'url' => env('REDIS_URL'),
//            'host' => env('REDIS_HOST', '127.0.0.1'),
//            'password' => env('REDIS_PASSWORD', null),
//            'port' => env('REDIS_PORT', '6379'),
//            'database' => env('REDIS_CACHE_DB', '1'),
//        ],

        'clusters' => [
            'cache' => [
                [
                    'host' => 'hubavocat-redis1',
                    'password' => env('REDIS_PASSWORD', null),
                    'port' => 6379,
                    'database' => 1,
                ],
                [
                    'host' => 'hubavocat-redis2',
                    'password' => env('REDIS_PASSWORD', null),
                    'port' => 6380,
                    'database' => 1,
                ],
            ],
        ],

    ],

However, I cannot write cache as I get the error :

>>> Cache::put('test4', 'test');
RedisClusterException with message 'Couldn't map cluster keyspace using any provided seed'

Something I do not understand : do my Redis needs to be setup and configured in cluster mode on server side ? Or can PHPRedis do all the job from client side ?

Ok, I finally switched to Predis client which has a simple and practical "replication mode" that allows me to use a decentralized but replicated Redis service.

Here is the database.php config :

'redis' => [
    'client' => env('REDIS_CLIENT', 'phpredis'),

    'options' => [
        'cluster' => env('REDIS_CLUSTER', 'redis'),
        'prefix' => env('REDIS_PREFIX', Str::slug(env('APP_NAME', 'laravel'), '_') . '_database_'),
        'replication' => true,
    ],

    'cache' => array_map(function ($s) {
        $parts = explode(":", $s);
        return [
            'host' => $parts[0],
            'password' => $parts[1],
            'port' => $parts[2],
            'database' => $parts[3],
        ] + (isset($parts[4]) && $parts[4] === 'master' ? [ 'alias' => 'master' ] : []);
    }, explode(",", env('REDIS_HOSTS', 'redis::6379:1:master')))


    'default' => [
        ...
    ],
],

My .env file :

CACHE_DRIVER=redis
REDIS_CLIENT=predis
REDIS_PASSWORD=my_strong_password
REDIS_HOSTS=172.10.0.1:${REDIS_PASSWORD}:6379:1:master,172.10.0.2:${REDIS_PASSWORD}:6379:1

Passing an array of connections to Predis client automatically switches it to "cluster mode". With replication => true, it operates in replication mode, sending Redis write commands to master and Redis read commands to one of the slaves.

Of course, your Redis service needs to be setup in replication mode. Predis client won't do it for you from client side. Have a look at Bitnami Redis Docker image to setup the Docker stack : https://hub.docker.com/r/bitnami/redis/

Do you solve it using phpredis?

for REDIS_HOSTS=172.10.0.1:${REDIS_PASSWORD}:6379:1:master,172.10.0.2:${REDIS_PASSWORD}:6379:1 is the cluster mode on in the AWS on?