Laravel Horizon not executing pending jobs - Kubernetes and Docker environment

Question

We have two different pods in Kubernetes for our Laravel app,

• one running apache serving on port 80, (CMD /usr/sbin/apache2ctl -D FOREGROUND)
• and another running worker (Laravel Horizon) (CMD php /var/www/artisan horizon)

The issue is when I check the horizon dashboard, it says 'Active', and I can see the Jobs in the 'Pending Jobs' section, but they never actually execute. They are just sitting there idle.

Now, when I SSH in the pod running apache and manually and run the command 'php artisan horizon' than it actually executes all pending jobs.

I have already ensured the followings:

1. Both the pods are connected with the same Redis database service
2. Horizon Prefix is the same for both the pods

Answer 1

Double check your APP_ENV matches one of the environments in the horizon.php config. Otherwise horizon will not start any queue workers.

By default only local and production environments are provided:

https://laravel.com/docs/8.x/horizon#environments

Answer 2

After struggling for days, I got the answer to this problem.

While using Redis as a cache, queue, or broadcast broker in the docker environment, we need to make sure that the following environment variables are defined properly and they must be the same across all the pods.

• CACHE_PREFIX
• REDIS_PREFIX
• REDIS_CACHE_DB
• HORIZON_PREFIX

Hope this will help others trying to deploy the Laravel apps using Kubernetes and Docker.

Answer 3

In my case, I need to change my app environment from prod to production

APP_ENV=production