Redis connection timeout error

Short answer: It occasionally occurs when we add or remove the number of compute capacity we need. Please refresh the page after a few seconds, and usually, the error disappears. However, if it does not disappear after a few minutes, please contact our team. We will get someone on it right away.

Predis\Connection\ConnectionException
Connection timed out [tcp://redis-xxx-xxx.redis-xxx.svc.cluster.local:6379]

Long answer: Redis is an open-source in-memory data structure store that we use to store MailWizz mutex and cache files. It allows us to speed up the application to deliver a better user experience. It does it by keeping everything in memory (like in your brain) and will enable us to access this quickly. Redis can sub-millisecond response times, helping serve millions of requests in real-time. Our infrastructure runs on Kubernetes, a cloud container orchestration system that allows us to run software like Redis on a big scale. It will enable us to expand when there is demand and minimize our compute capacity when there is not much load. During this process of scaling compute capacity, there might be brief periods when a request does not get a response. That is when this sort of error occurs. Please refresh the page, and it should most likely fix itself. Kubernetes allows self-healing, which means if something isn’t working right, it will try to heal by creating a new Redis instance in its place, and the new instance will start taking in the requests.