# Cache Prefix Analyzer

Category Severity Time To Fix
✅ Reliability Major 1 minute

Class: Enlightn\Enlightn\Analyzers\Reliability\CachePrefixAnalyzer

# Introduction

laravel_cache is the default cache prefix for all Laravel applications. If you share the same cache servers for multiple applications, this may result in a collision with other applications.

Some examples where the collision can create issues are as follows:

  1. Queueing system: For instance, a queue:restart on any one of the shared applications (that share the same cache servers) will restart queue workers of all applications and a horizon:terminate may terminate Horizon running on all applications that share the same cache server.
  2. Rate limiting: Named rate limiters with the same name will share counts between the applications. So, for example it may happen that when you rate limit user ID 1 on application #1, it may actually also limit user ID 1 on application #2 that shares your same cache server.
  3. Unique Job Locks: Unique job locks will be shared across applications if jobs have the same class name.

# How To Fix

To avoid a collision with other applications that share the same cache servers, you may modify the cache prefix in your config/cache.php file or the corresponding CACHE_PREFIX env variable:

| Cache Key Prefix
| When utilizing a RAM based store such as APC or Memcached, there might
| be other applications utilizing the same cache. So, we'll specify a
| value to get prefixed to all our keys so we can avoid collisions.

'prefix' => env('CACHE_PREFIX', 'my_appname'),

If you use Redis, it is also a good practice to use separate Redis cache databases when sharing the same Redis cache servers.

# References