In mod_jk how do I create a hot-standby or backup only worker?

Issue

• How do I toggle the status of mod_jk workers?
• How do I configure workers.properties to have one worker as active and another on hot-standby?
• How could I create a worker to act only as a standby backup that is used automatically only if the primary workers are down?
• mod_jk load balancing/failover.
• When one of the backend jboss nodes goes down for maintenance, we see EWS still trying to forward requests to the dead node and timing out intermittently. What is config needed to make sure no requests sent to the dead node until we complete the maintenance.