Docker number of replicas?

Question

Docker

Hello. Tell me, how many container replicas should be in swarm? Let's say I don't have workers, so I need two containers on one manager for fault tolerance. If workers are added, then 1 worker = 1 replica? Suppose we take in a vacuum that I have a hundred workers. It turns out that you need 100 replicas of each container? Or how to correctly calculate the amount needed for fault tolerance?

Answer 1

Having multiple replicas solves two problems: fault tolerance and scalability. It depends on what problems you want to solve as many replicas and do it. For fault tolerance, two replicas or even one may be enough. For scalability - depends on the implementation of microservices (whether the algorithm is scalable).