How to monitor back end jVM and make pool member down?

create a special monitor for each pool member and assign it to each member.

for example your pool consists of jboss1 / jboss2 create a custom monitor called wm-check and special the IP address and port (TCP) under the pool member assign this health monitor to jboss1. repeat for jboss2. Now if either of those servers fails - jboss1 or wm1 that pool member is marked down and traffic re-routed. same for jboss2/wm2