I am trying to work out how it is possible to wait for one backend to be available (UP) before allowing connections to another backend.
I am using Ubuntu 16.04, haproxy version 1.6.3-1ubuntu0.1 .
I have 2 frontends and 2 backends configured. One is for a web service (REST Calls etc to a Wildfly Server) and the other is for a messaging broker (ActiveMQ). The ActiveMQ backend is up before the Web Service frontend. Unfortunately due to items out of my control the WebService and Active MQ are on the Same machine and linked. What I would like to achieve is for the WebService Backend Server A to be UP before HAProxy allows connections to the ActiveMQ Backend Server A.