…e request to the died instance==>got message about “service is not available”. How to resolve this? My expectation is that if fabio does not recognize the died instance, it may route the request to that instance, that is fine, but it has to recognize the result and forward to other service instances in case an instance is died.
You must implement retries at the client side… Fabio doesn’t really know what to do with request that sent to dead or slow instance. It cannot know if the request was partially processed or not processed at all even if it received on of network/timeout errors. This is your decision if it’s safe to retry specific request.