I have apache fronting two tomcat servers. Both servers are active in the load balancer. If I kill one of the backend tomcat processes, all users on that node receive a HTTP 500 on their next trip to the server. I'd like to avoid the 500 making it to the user – I'd like mod_jk to see the 500 and just send the request to the other server. Once the user does get the 500, if I refresh, the request is sent to the other server. Why does mod_jk return the 500 to the browser instead of trying another active node?
Our application is stateful, but we have done the work in our application to save state and key times. So if we could get the failover to be more seamless, we would get the user experience we are after.
Here is my workers.properties file
worker.list=router,jkstatus
worker.router.type=lb
worker.router.balance_workers=worker1,worker2
worker.router.method=Next
worker.worker1.type=ajp13
worker.worker1.host=localhost
worker.worker1.port=8009
worker.worker2.type=ajp13
worker.worker2.host=localhost
worker.worker2.port=8010
worker.jkstatus.type=status
Best Answer
Since jk 1.2.20 you can set the property
fail_on_statusfor workers.See http://tomcat.apache.org/connectors-doc/reference/workers.html for details.