I am implementing microservices API however not planning to have any message broker. API Services will talk to each other with WebClient/web flux. Not using any message broker due to skill/budget challenges. Is there any risk of going production like this? what are the drawbacks like failover/replay?
It really depends on your requirements. A message broker is well suited to asynchronous, event driven applications. For request -response, I recommend http. A message broker provides additional capabilities. For instance, you get guaranteed delivery, partitioning, which is important if you require strict ordering, and a dead letter queue can be used to track and remediate failed requests. And as you mentioned, replay.